bal

beberle tee

oon nen nenngeen Natt eee at

Copyright N°_19 2.2.

COPYRIGHT DEPOSH:

ee oy —

jis
i

ny

ale i

DEA

Be ol ann eee

=

WORKS OF PROF. C. LARSEN

PUBLISHED BY

JOHN WILEY & SONS, Inc.

Exercises in Farm Dairying.
By C. Larsen, M.S.A. The Loose Leaf Labo-
ratory Manual of The Wiley Technical Series,
J. M. Jameson, Editor. An Elementary Man-
ual for Agricultural High Schools and Colleges;
a Practical Guide for Farmers and Dairymen.
4to, paper, $1.00 net.

By McKAY AND LARSEN
Principles and Practice of Butter-making.
A Treatise on the Chemical and Physical Prop-
erties of Milk and its Components; the Hand-
ling of Milk and Cream, and the Manufac-
ture of Butter Therefrom. By G. L. McKay,
Secretary, American Association of Creamery
Butter Manufacturers, formerly Prefessor of
Dairying in the Iowa State College, Ames, Ia.,
. and C. Larsen, M.S.A. Third Edition, Largely
Rewritten. xiv + 405 pages, 6 by 9. 133
figures. Cloth, $3.00 net.

By LARSEN AND WHITE

Dairy Technology.
A Treatise on the City Milk Supply, Milk as a
Food, Ice Cream Making, By-Products of the
Creamery and Cheesery, Fermented Milks,
Condensed and Evaporated Milks, Milk Pow-
der, Renovated Butter, and Oleomargerine. By
C. Larsen, M.S.A., and Wm.White, B.S. xili+
298 pages. 51 by 8. 46 figures. Cloth, $2.00net.

PRINCIPLES AND PRACTICE

OF

BUTTER-MAKING

BY
G: L: McKAY, Dr.Sc.

Secretary, American Association of Creamery Butter Manufacturers,
formerly Professor of Dairying in the Iowa State College, Ames, Ia.

AND

C. LARSEN, M.5S.A.

Professor of Dairy Husbandary, So. Dak., State College, Brookings, S. D.;
formerly Associate Professor, Iowa State College, Ames, Ia.

THIRD EDITION, LARGELY REWRITTEN

TOTAL ISSUE, SEVENTEEN THOUSAND

NEW YORK
JOHN WILEY & SONS, Inc.
Lonpon: CHAPMAN & HALL, LimitEp
1922

*
}

Copyright, 1906, 1908, 1922,

’

; ey
G. L. McKAY anp C. LARSEN

e

PRESS OF
BRAUNWORTH & CO.
BOOK MANUFACTURERS =
BROOKLYN, N. Y.

PREFACE TO THIRD EDITION

THE science of dairying is constantly broadening. The
methods and art of manufacturing the best quality of butter
have gradually changed in conformity with the scientific prin-
ciples involved, and no one should now undertake to manufac-
ture butter until he has made a careful study of the principles
governing the best methods of manufacture.

The authors admit that, in our present state of knowledge
and experimental progress, it is in some instances difficult to
distinguish well-established facts from those not universally
confirmed; hence, it has been their object to give only informa-
tion supported by the preponderance of experimental evidence.

The first and second editions of this book have been received
by the dairy schools and the practical creamerymen ‘mn a manner
indicating that the work has met with general approval. The
- third edition has been carefully revised, and additional chapters
have been added. The new chapters are: first, Defects Found in
Butter—Some of the Causes and -their Prevention; second,
Neutralization of Cream; third, Milk and its Products as Foods—
High Value of Milk Fat; fourth, Cold Storage and Butter for
Storage Purposes; fifth, New Tests, including Accurate Method
of Determining Per Cent of Fat in Buttermilk, Skim-milk and
Ice Cream. The authors’ endeavor has been to bring the book
strictly up to date, and to include the latest and most approved
methods in dairying.

The authors believe that the subject of dairying should no
longer be treated as a whole, and for this reason have treated
special branches of the subject. In this volume they have en-
deavored to give such scientific information as relates to the
manufacture of butter.

in

lv PREFACE

The scientific knowledge embodied in the present book has
been acquired, from time to time, through work done by various
investigators at different Experiment Stations and by leading
scientists of the Federal Dairy Division.

It may be added that the statistics and tables given in this
work have been quoted from noted, reliable authorities.

The authors are indebted to the following companies and
individuals for the use of electrotypes: Cherry Brothers, Cedar
Rapids, Iowa; Waterloo Cream Separator Company and Iowa
Separator Company, Waterloo, Iowa; Vermont Farm Machine
Company, Bellows Falls, Vermont; Burrell & Company, Little
Falls, New York; Empire Cream Separator Company and Jensen
Creamery Machinery Company, Bloomfield, New Jersey;
Dairy Queen Mfg. Company, Flora, Indiana; Elyria Enameled
Products Company, Elyria, Ohio; Rice & Adams, Buffalo,
New York; Worcester Salt Company, New York City; Russell
& Hastings, Madison, Wisconsin; Louis F. Nafis, Creamery
Package Company, Borden & Selleck Company, De Laval
Separator Company, Arnold & Company, Diamond Crystal
Salt Company and Davis-Watkins Dairymen’s Mfg. Company,
Chicago; Kirschbraun & Sons, Omaha, Nebraska; Professor
M. Mortenson, Ames, Iowa; and Strawberry Point Creamery,
Strawberry Point, Iowa.

G. L. McKay.

APRIL, 1022.
tg C. LARSEN.

CONTENTS

CHAPTER I
PAGE
HIsTORY OF BUTTER-MAKING AND COMPOSITION OF MILK................... I
rey (I DYevabab titer toyi IMI 2 Sa ae eee i OS COE Re eee 3
PeECompositionvoreViilkn st 1 wesw kash sek. 2 si, ee fo ee aes 4
emanation Oled otal Solid sseewn eae ce csc kn. :< SNE oho, 3 we 5
éilis VGN ahs Restate 8 CRESERRE E os: LEEE ety Go ERT Ps Fee REI 0 ohare nea aa 6
Sie dE Raa Da TN Eo A 3 PR EES ee Sen 9 8
OME FODELUICSIOLPEaL. . a aNMMrer a... 0s qRpap Mell: 5ick) ee ae ae Ret toe fe)
Fem lycenides of at... i Mempe ge... NRMR oe pe ere pega o£ Os! 10
See CON GIEOMEOLE ats: (\2yammMmr: ... . A aemempmemes ys cs Sein Sree cA Oe II
g. Theor:es in Regard to Films Enveloping Fat Globules............. II
Oem CLASSES HOLM GES: se eee iirinn) SRec rans ear anniae pee ee ee Gel en WC 13
FARM olavtil etc 4 tenes halon, ape aim Mame tA Melia Mt, oe 13
BeeNonevOlaitile:.:.< soa hen cas ote MaMa mie oc 05. cM Me oe RUA ee 14
Lia Composisionror Usiitter: Palteiern.: = eae ok... ee ee ee, ee 15
12. Proteids (Albuminoids)......................... sae Mra Risa ay 16
dene CAVSIEITO a oe Mea RR A 2 CR ee 17
15}o. GANDY UNA eNom oN ie eee oe nk ch NT ba aN eB aais T 18
TG IS TENT so ee SIC = ec a eae alee ae An JE OU eT De Oe 18
TAL, * ANGI Og bee RELA ro cst ee a ge Ee a Re A oe VER kT AU ALO ae)
pgemGa SCSVON, | VAiI Kke, U RM Maree EA etc cttihc a ease tep at a ibe ee cil (U Se 20
nO; (Colkoriiayes WENTIER. 5 oococabeoseocegeucoce a5.) Nace neater Wa val es. 4 22
7A Och ery Constibuentsrole Vill kemeenmnrr tre aarti menace ae 22
CHAPTER II
INNER: SROREMIONE se ors api acetate ara si Cem es eT Rae ie a 23
o) Mammary Glandiasa secretory @ncans. 9 shee aehy a oe. 23
Peeintemmal stricture Cow si) Wddenmenre i. . eee eae, ae 23
ee theonicsio taille Secretion: .jammmmenmcr mr uohulht ts ee nes We 26
42 Conditions Afiecting Secretiommem Miike.” 222 oko eo ee. 28
Feat xternaleappearance of Udderemcn tne 4-008 «ce (he dene PAHs
(Gis UENCE on PRR co, ARAN Ree ee eT RS 30

vi CONTENTS

CHAPTER III
PAGE
PROPERTIES ORS IVDM Ree sues: . nga Ree enone ORC Cote ae oie erneee 32
ATC LOT apy oo oc 2 shed aT, he 32
Dh, TENE NGO} cy lee ae RENIN Ocoee: BARES Yn hcg gee eager aat to ig ln 32
a sOpacltyvor Mak. «2st eed ae CPs cia cee ee «ane Be
Ae Chemical Reaction of Milks Ase yee cane os >. eee 33
Gar speciic Gravity: Gf Milka ioc. cence ssc «4. Aen 33
6: Natural Separation of Milkeand/ Cream 2 eyeee 4.4. 4: 2) scree 35
os ONdivesion: Of. Mille: . .(yareeenne c-siye- Meee eet: acs «cc ha eee 37
Se Viscosity of. Mal: cyseaeneenns .scn kee ceuekote a's + alate Seantcnees: airaginaee 37
oe Speetic Heat of Mile ed ta cess earn eq ce eo eae eae 38
TON tection High HHeabmevont propertiess ofl iil isle rien nee 38
(i) DWyasioronys mearlky alll Gemons, oc6oncscass0casd55055a05004005 39
@)DiminishesMVascosityjorn Body. .4- +5. -he os eee eee eee 30
(@)MDrives oltdGasest re ae taetecn 3 ae se ete thn ey od Oke 40
() Amparts*atCookedi(Wasterer..:..-/.. 2 heparan ae pees 40
(5) Precipitates Albuminoid and Ash Constituents.............. 41
(6) Destroyseroperties of Enaymes.. . aqeeeee nes aur eee 4I
(7) Divides the Clusters of Fat Globules....................... 42
(s)Caramelizesthe:Sugar veces -.: 4. Memeo neo: aan eee 42
General Remarksyivs sx chic details ocx! ose) teat SPaRisy sno cis ester ae 42
CHAPTER IV
Mrtx anp ITs Propucts As Foops—HicH VALUE OF MILK-FAT.............. 43
rt. Chemical Classification of Milk and Its Products as Foods.......... 44
2. Biological Classification of Foods...................-.2--0.e000-- 45
TA PTO LEIS yee eee cin ec ance ane SAN Gee RRR ght CED ace PoDe eae thea ee Be ecg ace 46
IBA Ashvor Mineral Miattterk 7.22.5 ects 0c oe eee 46
C. Two Unidentified but Essential Food Substances............. 47
CHAPTER V
PAE RIENDS UN) INIT feces a Ch. so asean cy suche] is Silay sd) nod ase Res 54
ig AD) SfAMUGTOM a2) be ok an ea Simic uabaneeen cre ape acts niece ayaa eee 54
AM Classiticationlof Hnzymiess ye oe a- eee erate ce anes 54
2. Size and. Shape ol Bacteria .:5 0.5.5 ues. 2k oe te eis) o ene 55
3. Favorable Conditions for Bacterial Growth....................... 55
GA SAE OO ait se eared a) 55) b: 40s ao ate le Rane ee ee cee I 55
IBS Wemperature se Gey. Gera een ete sae one neste Nae see aia 56
G. AMioisture ea. ee ee 58
4. Unfavorable Conditions for Bacterial Growth..................... 58
Be Kands) of Germs ound in Milk . . Seer tte 2 ete ee 60
(, INfuhanloie @? IBeewenie) tim MOU, Jo encoos esse nouaudWavadoccsadcens 62
7 aSourcesion Bactenianin Vill kere 0. .°) . ° iy yaeeeeenemenets ees tree tetera. ene 62
8. Effect of Thunder Storms on Souring Milk....................... 64

CONTENTS vil

CHAPTER VI
PAGE
PAVESIN () RUNIEA 0 V [EGE Keawag ate cos, 2 te PRUE: ach suet SA cyl SUE ig ct 65
rie (CONC STEI00IN L Rs SSs Rae Seed G 1c ene Ree cee 65
Dee Salli tay a VTA RA es, << RACE SCRE i: Se SPP ease ea a tS eee 66
Bye bloody Or NeGeIViilk. . .:. Waegacrsa. : 2s scp 1S A. ae eee fein 6x 67
Zea) BANU, IN ETD eigen ae Sree 3 Sat OR MERRIE Ire, Golo eC ate an ee av 68
SNe Hhoniy NUN eas Sak ae 2! CTS op eee pe a 68
Oa uRO piyge Vin Ke set gsay 3) upp ee Rae. 3 <n « Sioa eRe Meme Yeo, eld 68
see) Binal Sie NAY Uke 5 a etenes eee omc biter coe RRS | kkco'td y ace a Ree Reon 69
8. Milk from Cows which Have Been in Milk a Long Period.......... 71
Op MialkeiromeSpayeduCowsm cee ae si. «,0 +. Rae oye in sa ates: 72
LON MilkairOmMmolcka COWS sae a tectcicen oe Ginis + « cman teense oe ances 72
CHAPTER VII
VARIATION: OF SHAR iN y MTT ANID CREAMEI see!) 011.) een es 2. 74
PART I
VARIATION OF FATIN MILK............ $6 'e, oc ORE ET PN Gal 74
reilndividuality Of (CowsMer wi0: caiiscssn eee aa ee actin. hye ae 74
QEUBTEETLOI COWS! Aira SiN stk! aie dee ce area Maen MPTP NRT oral! A These 75
Gon eHDeL WEEN avila e Sr kate eek eye ieene, wil Se Wiehe Sulede ree) ce 75
Ae Mannermots nll go aaa eae uane |) ok NaNO RRS, OS PPR Ys 76
Se BOTCHAM GRANTOR EVIENLK., Steppers... ARERR co... aren rene CRORES 2K 77
Gin VANES Olr (CON Geert ARNE ec. co ORES 8 2 NO et ye cn Sa 78
PRENGVANICERMMCACEA TIONG ceric: \<j<.o Mee ee ds eR 78
SRA CEU OL COWS ieee Ctecra eae rs Sik use EE eT eee Pn | Mart Li 79
OMPETAVITONIMEN torre ee meen. Site areata ene cere eT UE 80
TOyee Ondition of. Cowper ectesec dons ck fue farce OR Re ee ee 80
PART JI
WARTATION! OF) FAT dN (CRIWAMi mane eter atyay «<2 MORN ay taste hoes Sekar 81
Ten CLEAIMUSCLEWAGIUStMENt Meena) eee eee nee ee 82
2AsRIGhMeSseO he Milk: Ar ncte keiee a n he PON t we ee Moun. UN Wee, 83
aH NATE RO pM O Ws si-g eacteyeh lakes rt ia 9c a ES Re a 85
AM ODeC RO hei A CHING 4 2.45 tres co. oo PM ee a el AP 87
lem perature on tN ee ase ROE oa hs AGRE Me Mo ack, 88
6. Amount of Water or Skim Milk Used to Flush the Bowl........... 90
CHAPTER VIII
RECEIVING, SAMPLING, GRADING AND TESTING MILK AND CREAM........... 92
1. Receiving and Grading of Milk and Cream....................... Q2
A. Detection of Abnormal Milk and Cream through the Senses... 93
BOSerotr Acid Teststn wren 8 ne tt bY Una 04

Vill CONTENTS
PAGE
C-Useloi hermentation ests... caemimeeney fan ee five see 04
a. Gerber and Wisconsin Curd) Testswey 24, 00) eee 95
DGrading Milk by Heatings’: : 7.5 ieee tt area nee 96
B. Wsevot Babcock Testiand Wactometerpnre..- 1 asane ete 97
a. \babcock Test ote Minllee (2 aera oks sec cs Ne eee 98
by Babcock Test oM@ream ear i ce en) eee 99
c. Does the Babcock Test, as Ordinarily Applied to Cream,
Give Too High a Reading?.......................... 100
d. Babcock Test of Buttermilk and Skim-milk—American
Associa tion@lesberes jcc vtomtiion wreccn © «6 con amine eee IOI
é. AmericanvAssociation Mest. .¢ee ema. so sn eee 103
f. Determination of the Per Cent of Fat in Butter......... 107
Fe Sediment: Vester: cocks oes eo cea aces eo ieee 116
24 Necessity ‘of Good Minera aaj 05.2 Sane ie sae ane eer eee 117
3: Sampling: of Milken ergs ccs cvs a Siergnct iw ate vcue eee eeersmtantan eaten ra eet 118
a. Sampling Lube spartan sa cic este e eetecs «wae rateecheeeial dae eens: ee 120
5. sampling Churned@ Mille. gies oe. s.r ene ae ae 122
Oi raze Milks. ee, wea, atee ooRnne s+ SOR en aA AS oR 123
7. Sourand: Coaculated i Miilk .. .: States ia.- ss dae paaresisuetans ote aeteners 123
SA pportionings Skima—mall ke /-/ sree). einer ee aie are eee 124
©.) Washing: Cansi)24 4 arcs einve sac ae Soe lo ee + 9) Ne ee a 125
CHAPTER IX
(COMPOSITE (SAMPLES)? 2) eo iettleeca.o 2 acne hades fof ace RIG ea 127
Te WERMITION:: ABs. 4... Seals 4) eee te ees. eee 127
2. When tolSamplere ea.s.6 acts. ene els Oe ee ase eee 127
3. Kind of, Presenvatives, to Addi age... a2 sneer ners cine ern 127
A Arrangement of (Composite samples: -. = ante ten ies)
5. «Gareor Composite/Samples, cee). .n52 ees 2 ae 129: -
6: ‘Average Samples schy ys fat tdes cus/ouis gee gals 3 Rl aN ed eee Ee 130
7. Composite Sampling without the Use of Preservatives.............. 130
CHAPTER X
CREAMERY CALCULATIONS. 05.) suis ave a Ueno seis AGI ee eee 131
T.Hind Average Per cent of Patel) 3.00. eee oe 131
2: CalculationyoOverrun..i 0%, 28. 4 oa ee 133
(@)) Thoroughness of Skimming.) 325..4- 0 dae eee 133
(2) Completeness/of Churming.). 2: hi .1e ae eee ee 133
(3) }GeneralLosses'in’ Creamery... s4¢0- > See ee 133
(4) Composition of Butter Manufactured...................... 133
3, Calculation of Churn Yield... ........ (aeeeeee aes eee 135
4. What Should the Overrun in a Creamery Be?..................... 135
5. Calculation of Dividends:s ....... .:::\. : eee nee deo ee eee 137
6: (Cream) RaisingiCoefficient: . ..-)...../.. |... eae ee Se eee 140
Ta Statementato, Patrons. 4 3.) edo!) eis/s/s 4 Eee as Cee een ae 140
8. Paying for Fat in Cream as Compared with Paying for Fat in Milk.. 143

CONTENTS ix

CHAPTER XI
PAGE
Beans Mn Pervious TO SKaemme. 2 oo LLEes.. Yas Se AS 145
Fee AMIS AOE AEIOAGINGE.. 2 es... J ee SE ek 145
2. Advantages of Warming Milk to High Temperature Previous to
DAKINE ie: oS = > - Sa ee SS OTE 18s os one 146
pe AWE RAL EEN rs. s. eRE 5 | Sh ele Ors x 28 aoe Doyo 2 147
CHAPTER XII
SET ES og er, > 149
RON EEE 0 Go) eee ee ee oh. | il eat tas 149
A. Shallow-pan System....... erie. 2’... eee. a es 149
Ee eek AI OPERA St 27. ee ee ae 150
wa Droits Waseem oS. | 2 ee ee ee 152
C. Water-dilution Cream (Hydraulic).......................-. 153
Pn LEAL EAU ee. eS ee cee 154
ALP AI AgeS: eee... | eee) Oe ee ee 155
B. Hetocy of Centatingal Separators... 2.0022! 22 sel... 155
ee Mipaiess Sesristpemren >. > sce ee Se eo oO ue ce ees oh 157
P Clasatentamunt pe paeaions. 250 re oe eee. oe cake 158
BE EES AN STAR ARME 5) TE CUMIN ee or a oe ee Ee 158
F. Conditions Affecting Efficiency of Separators...............- 161
gaManner of Heats Milks =o. re. 161
Pee mutiion Of fie Mice): Sess. Pe OE 163
parcricrdine {ie separmiotnes2..- - 2): sean = 22h eevee 163
PSUs St be ate Oe a ot: Se a eS = hae AES Ae 164
Ps ee Aeaibarss Aik Rett, ee 8 ck Orel ee at oS oid 165
yp Re TSS es eR eae aS SS aero ek 165
NUS Fc is ie a SO eae cy 165
Be GERARD EISEN ls 2 SE ate Sulit on 5,5 166
CHAPTER XIII
Ee UE REOMEERS. Rn Nt, Se ee nee ests eee eS 168
£2 inttrodtiction of Parm Separators. 2.22573 22 22226 60-5 i le eee eee 168
2. Reasons for Introducing Farm Separators...................-.... 168
erOnicciins te Parmrscparaives-co se. 2 171
Ey AVC MESO KeAnY® -. 2 7 Es Si oo al Os Soe ee ee 172
5 Lower for Vann Separators. (sue oo sie. 2s oe sae Sees eee 174
Syeaeoikercamign tic Faris erepes 22205 65sec ee sl 176
Poe ee See 8 Gye er SP ean ee iy ee a 179
i meena ee Creaithc eee) eee 3. eee ete eo fey okey 180

en Mapas iiter cx Sian 2 ee ST et 180

x CONTENTS

CHAPTER XIV

PAGE
NEUTRALIZATION—THE “NEUTRALIZATION” OF CREAM................... 183
7, Wienimillvaniom, IDA IS OF. ococcacnsc00ccsvseucnecausovenunece 183
2. Neutralization of Cream for Butter-making....................... 184
3. The Preparation and Use of Lime as a Neutralizer..... Maer 192
4. Pints of Lime Mixture Required to Reduce Acidity to .25 Per Cent
(CVAD EM aa a 5 oi cg 196
is. Other: Neutralizers vy arene orev anr aire kG e's lclos ae 199
CHAPTER XV
IPASTRURIZATION sais + 3 kicageteneeent rer ag aaa eal e alc) ona hae Ta Ra 201
T+ DENMITION: 5.0. aE aie eee eos nee ceo al CI ee 201
2a Storch) est torhasteunizationl = ore e eae ene eee eeenee 201
3. Pasteurization Temperatures.......... Pen ite West St met ae Ac 202
4. Good Milk and Cream Important...........................-..- 204
5. Sanitation Must Accompany Pasteurization...................... 206
6s) Methods of Rasteunizationy .ssaqene ss. .- | 2 ane een. eee 208
A. Flash or Instantaneous Method...........................-. 208
B. Vat-or Holding Method...............................-..-- 208
C. Combined Flash and Holding Method...................... 208
7. Mf clencysOl ekasteuUniZenss.. coe aaAcia ee ee Oe Ce ee 210
8: Cost iof Pasteurization 40th cae is ee OO nee 212
9. Disadvantages of Pasteurization..................-.-.+--+00-0-. 214
ro. Advantages of Pasteurization...............---.+-2--..-----++ss 214
CHAPTER XVI
CREAM RIPENING: AND) STARTERS .6 4) 45 02sec ne so ee eee 215
Cream Ripening:
ae Dehimition ys. Waku yelctseyaireeedsns cate Sakyar saan oie cee ae eRe asters be. 2Us
2) Obyectso1 Ripening jccnenerde chess. as «2 2 se ee See 215
Beeupening lempenraturexoig @rea Tae se eer nee eee 220
4. Amount of Starter to Add to Cream.........................-... 221
5- Mixing the Starter with the Cream....................-.....--:. 221
6: Meststfor Acidity; 6... 5 sik eee oes Oe aoe eo eee 221
AL. Manis Testy. cc6 6s. o.2 os each Slept Fee re ees oe 222
BY Barrington: Tests. soca s kh ORO OC O: Lee oe 223
7, Degree of Acidity that Cream Should be Ripened to,.............. 224
STARTERS:
Sep enMiUOMs..) «hoe aseiels doe sesestceleon sw 6 5/2 > SOOO Eee ieee 225
(Osi BOT (0) pi Ae te eee ei A ERE csc oltabe Wioibas OHRo ad's 0 226
Tow Classifications of otartersin-444- -. .- 46 ean nen ane ene 226

CONTENTS x1

PAGE

ro Commercial Starters or @ulturess... so cceee.. nse s ss ee eee eek 227

ngaebreparation:or Commercialystanters. |.) sees see 1 4sss esses se: 230

AMMO CU ALOMAR cic) =..s: oc eae: oh 1 he Ses oe cee ec it er ns 232

roam VinikePowdertonm otarters.<ueeeies.*. ci ueteiei Ceee dein te bh oie. 235

16. Length of Time a Starter Can be Carried........................ 236

TR OOMStATUCLS Hic. EP miss. i ameewe es ee rene ee eee sie), 236

18. Under-ripening and Over-ripening of Starters..................... 237

TO Ato DAE Ore Shen to) WSS gag acoaceoedeeeocosoccocnsuuesseon neers 237

ZOWUSCLOMOtATte=CANSS jah ts ase ais 2a re en Epi ae 238
CHAPTER XVII

CHURNING -AND) | WASHING (BUTTER (2,0 50 o4:0 diay os). = «sc Eee eto, Les 239

Ties I DAS AVATT ATO tac area nceks IS ee Ce oe CeCe RETR Goce ee ienens eae 230

2. Conditions Affecting the Churnability of Cream................... 240

Alea eI pera LUNE 5 traeetensre iavcpency te ake Gina hn SRR oe se Not on 240

B. Influence of Length of Time Held at Churning Temperature... 245

GORichness: of (Creams o>. oe wp echt 5 o,. oacearen Sere a aerate 245

DeAmount.of CreampinyChurnse sees) eee eee eee 247

Ee DCPTee Ol RINCHEssw eh... 1 Sees Ne eee ec Pe, A) a 248

PeyNAeUTe Of Agi bat loner a5 eicugsl ie Coe aeeele Cpe ciee eget ke tke ge 249

GM SIZE OSH ata GIOD ULES ccl cues Cue ORC ca eh tue HY 252

Bro traumin gO fy Cream tases ccd saw ere err me oon lee vata S Sashes 253

AraC OOM ern Ae a eee A dee rN Sta oR ke apn ac RR 253

Pe henatorstoprtie Churningar Pr rminnnne sce. 1 Nua ie ieee een 255

os Churningavinxed Sweet andrsour Creammn 49... ee oe wae oe 258

fom Dike Ut M@mUTMIN SA. toate |. oy pee Ae Sua mains A GARI, 258

See wceping) Churuni sweet Conditionss ae ew). eee ees a 260

9. To Prevent Butter from “Sticking” to Churn.................... 262

LOMA as hinte.On DBULTCRMMmE Te Swen Nut oe rte Mees Pee nye Pe oh 263

ABS IUTDOSe OL WWiashiIley orc.) a tickekic sn | <i Reena GAO nese arty 263

Belem pera nero AS MMW ALeTe See. er. = eines ee ee sone AOR

@™ Kindor Washuwaterto,Wsey. 1.1.5... scsi Ua ater 265

t1. Methods of Purifying Wash Water........................0.---- 266

Abs Eiltra tion... satan, acts ere rei tA Bais, ete athe ee aly 2 266

a. Continuous...... Stent: IN Abe re ase. 2. X86)

bylnitermittentys. s4 0) pees ON score Stee i eek oo ge 5 Die)

BRO ASCEMEIZA TION ease 69.16, RRR CeO is ene the ees - 266

12. Advantages of Purification of Wash Water............sceseeeeees 271
CHAPTER XVIII

SALTINGS ANDI WORKING) OF UBUTTER cj nemeine Samana cette eit \rrees 272

Tee ODJECESHOMO ALLEN \5 5 ||. ANY eee eenet as Puen Rin Reyne cca 272

2. Amount of Salt to Use to Produce Proper Flavor...............5.. 272

3- Effects of Salt upon, Keeping#Properties;.< 7. 2242. .282 255: . es BB

xil CONTENTS

PAGE
4. Salt Facilitates the Removal of Buttermilk....................... 275
5 saltini elation to WatersneBubten: 9 cise aot coca erences iaicieg: 275
6.) kind and) Condition of Salt#)- 3... 2... seeeeee nen ne cere 277
bei Gaal teiall 3401 ie) ee ene, Ha en SENSIS. (G5 6 Os Gimee aim devo o b.n/od oi 278
SMottled Butter ..6 6.0). seit wk bie seem IOI octets ee Meerut 279
g. Prevention of Mottles in Butter..................... 0.02 eee eeee 284
to., Curdy Specks in Butter: cea ys. ioc bape a cicl> soe eee 285
Tr ibrine Salting... Ms <2. eee 1h eer amin tt 287
caer oti el DX cee ANNES io eRe ESE canoe a ete a ae 5's 00 '0.0°5.0'c 288
AL, Principles sof the Mlest ye 5 sci 24 soc sores os 2 ety eee te 288
B. Chemical Changes that Take Place......................... 288
C. Features of Practical Salt Tests... ..............0cseeeeeees 289
iD. Go Make arSaltmlesten .. 222.0. 1 LOR Sy Jal ec ako ay SE 290
134 Working, of Butterm@biectsiots.. 44 .4---044- ous see een eer 291
14. Moisture Tests of Butter....... EE Se OCT HAS AU. 6 6 6 2 293

CHAPTER XIX
PREPARING BUTTER FOR MARKET AND PREVENTION OF MOILD............ 204
1. Styles of Package and Kinds of Wood Used...................... 204
Dy SLOLing Butterne Creamentessn ee aaa eee eee 296
3. Cost of Manufacturing Butter....................2.-:eee eee eee 207
42 ibreatment of Mubsand Boxeseen see eae eee aoe ee eeeeiee 300
5. Paratining Oneiubsy. sie 8). lei ne, SOR Re Rn aout a seated 302
6. Paraffining Tubs Reduces Loss from Shrinkage................... 303
7. Lreatment of Parchment Paper..........:..----+-.---+2-+++-+4: 304
SaVeasts andwMoldsnmy Buttery = eae oe ei eee ea ae eens 304
6s. Mold) om, Butter cajo.cc Mirae ck cis eh. ccieeacs one: fa Sonne eae ye eee 306
A. Conditions Favorable to Growth of Molds................... 307
Be WMiscolora tions yi. ces acne ake dis Ne oaecce esac erea ree 307
C. Bropagation of Moldss).. ij 6 s)s<.c/5 pce ee Pee 307
D. Sources of Mold on Butter................ cece cnn ee ceee 307

CHAPTER XX

THE COMPOSITION OF BUTTER AND FACTORS THAT INFLUENCE ITS CONTROL... 309

1- Acts and Rulings as to Composition of Butter.................... 309
2. Compounds for Increasing Yield of Butter................:....... 310
suNeeditommReculations: - o's. 2. 5 aye eee eee eee ie anette 311
4. Control of Moisture in Butter.......:...02.05..52255.4.-552-058 312
5. Analyses of Commercial Butter between Thirty and Forty Years Ago. 315
6. Standards in Different Countries..............-..--++--52--0--5- 317
7. Factors that Aid in Moisture Control........... Be Oa ee Poe 318

CONTENTS Xill

CHAPTER XXI

PAGE

DeEFEcTs FOUND IN BUTTER—SOME OF THE CAUSES AND THEIR PREVENTION 323

PME at OLE LAS Neea Or 1) Meee v0, voy te mm NNNE teke le Bien cae er 323

ee Sta leMMAVOES Gree che Ss! ee Mae Seta eM MOR eM Bian taeda cee mss ce 324

ge Dlavors Acquired by Absorption: .. /5sseerer ee ee. a eee ras 324

Aba Cheese HlaviObe scree sty heed esac «oN Ree Rg oO Naa a 324

Gas STOLUN a) BIEN C0) ei rraee Re tea RE oe Ul aR ACARI CRS) Nee 325

@, lkynllsy econ COmMGltnOns, oococuacenougovdc0sccencangunaeranune 325

TMH CECE a ORS pears oid Ars a OE ae tae <i 2 oe MIR ace ieee A 327

8. Removal of Garlic or Onion Flavors..................+.--+..---:- 327

AbMRoworacieate sw ildiGarlicney. ci... Cee oe eA 328

g. Advance in Lactation, Winter Feeds and Stable Conditions......... 320

TOs Mallow Wlavioten cies ctte asta Meee ert coy as she oral RPE OUS ANIA rp crit 332

Teen Meta llicy Mla viOrs. Mac: Aoi tates tote ores oa vs PMO RRR Aah ohoateht 335

TOS hy A MlawG nates eg, Medan aimee ees wud Wiss hy eae cep ey ey a 336
CHAPTER XXII

JTDCING AND) GRADING: BURTER Sec some oes Seige 2) ae elcome coe 340

me Standard for, ju eines) ee, ee oe cee AR ete ene rs ties ose aieeeorsianus s 340

we MAINT x0 fal OTM ESAs aetna eae nc ewes NEPA NC Kate nan itt teen 341

leah 1BXOTS RN ts ree ER NREL i Gt te gM RR ort ee a a 341

TE OE AN OURS i505, 92) ei ad RAS RE a ae AI Oe Beto 341

CR Color Rss acne eteny Beis rt eee CERNE th aR Rn op URC.) We 341

Be S alleen inant Soe aL we Ry Rial AR eg ae eA eet 342

JOR TSA AUS eee Ares Go Catch eee ne Ee ote ans RE eo eT STURN Ane 8 342

3. Classification—Grades and Scores....................0. 00 cesses 342

Am New: York Classifications vers ve vsenac.s deel ane eels te ae 342

Be Chicagoi@lassticationt.ageeca ae eyed oo. ee ee 347

Ae Export’ Butters: awry ates See eR Ry pe 8k othe 2 Fe 350
CHAPTER XXIII

Co~p STORAGE AND BUTTER FOR STORAGE PURPOSES.................... 352

reoltistory.olColdsstorages, 1b -4- siuce pee ccs oe Fe oes Se ee ae ees 352

oe MechamicalsReinizeration... 5 (serene os saan se ae B56 3030375)

unb enetsroi Cold: Storage. «ots aio oie a lai ae - 353

Ama OS ty Of SEO RAG Cash 20 7.15 1. Rae ey a en dra i A Ee 355

5. Should Cold Storage Butter be Branded?........................ 356

Guebutterfor Storages.i)5 oc weWyee ne cre estan ye attra leik tee ty ere aN 357

7. Working and Packing Butter for Storage Purposes................ 360

XIV CONTENTS

CHAPTER XXIV

PAGL

Coornmne) PAcIEITInS FOR CREAMERIES: |... /..15.:0n eum nee St 9 ene 362
1. Cooling Systems—Natural Ice, Mechanical Refrigeration and Cold

WEEE ie ese aye c's w aaialngal SUMO ee nla a OR Oe a RE ae 362

ApsNatiiralllce Systeme as ce.e.) ace Dh Aan 365

ae kand ‘of TceyHouseheen. eee ee ances et saree 365

b. Size and Shape of Ice House.......................... 368

c. -Filling the:IceHouse:........2 Asatte: aed 2 eee 372

@. Source: of Ween es a2 aus set eeiege rie ons secre ee 373

B. Use of Ice in Cooling Cream................ sapolnd oguovae ee 374

a. Directlyas ec aie: a Se eer IS SiG. o ok 6 0:2 374

be Indinectlyeeerecere. » SAU ie Alias ee 374

C. Mechanical Refrigeration...................0.0..00--0e-e- BS

a; ApplicationmimsCreamentes seer eee 375

b. Chemicals Used for Mechanical Refrigeration........... 376

c. Principles of Producing Cold Artificially................ 376

(x) Compression’ . 21.50... Ree on eee oly

@)ECondensationss43ne ce. oe ee eee Pe e877)

(3) Expansion . 04 ac .,.,..0: Setyaeee oe eee 378

ad: Transferrme ithe Coldivis ..... 45 eee ee oe 378

CHAPTER XXV

ECONOMIC OPERATION OF CREAMERY..............00ccceeeeceeecceeeees 381

ZL. Firing, ‘the Boilers jess... ids) heaean ss) Go Ie Oe eae 381

2. Burning ‘Wood)or Coal. «......240 56 aucsue sneer cane ce ee eee 382

BeeDailyaWeighinerotCoallUisedaaer eer r eit ee 383

4: Cleaning. the Boiled. j2 2a ween wie tie eee 384

S. Priming of Botlerss. 2.5 ws: gchar se 0 eee 384

Geb evnyectors Re ee ee ie epee en CR Meee 385

7 (Oil Separators. oo yao. hese) st toes shart cliche ee eee Poe OS

8. Belt, Pulley and Speed Calculation... ..................-0eeeeees 385

APPENDIX
I. Legal Standards for Dairy Products.............00ceeeseeersees 387

IT. Metric System of Weights and Measures............ SPE os oc 388

BUTTER-MAKING

CHAPTER I

HISTORY OF BUTTER-MAKING AND COMPOSITION
OF MILK

THE art of butter-making in some form dates back to time
immemorial. History tells us that butter is one of the oldest,
as well as one of the most universal, articles of diet. We are told
it was used in some form two thousand years before the birth of
Christ. References are made to it in early Biblical and other
ancient history. We read, in Genesis, that when Abraham was
visited by Angels, who appeared in the form of men, “ he took
butter and milk and the calf which he had dressed and set it
before them.” The word “ butter” is mentioned in the Bible
seven times. It is known that the Scythians and Greeks used
butter in 450 B.c. A little later there is a record of the Persians
making and using it. In the early centuries butter was employed
in many ways. The Hindoos offered it as a sacrifice in their
worship. The Greeks and Romans did not eat it, but used it
as a remedy for injuries to the skin. It was considered by them
that the soot of burned butter was good for sore eyes. The
Romans also used it as an ointment for the skin and the hair.
This practice was common in Macedonia, and it is reported that
in many cold regions persons use butter as a bath. In Spain, as
late as the seventeenth century, it was found in medicine shops for
external application only. In the rural districts in Germany,
fresh unsalted butter has been employed as a cooling salve for
burns, and has been used to some extent in this country.

In early times, butter was not generally used as a food, but

2 BUTTER-MAKING AND COMPOSITION OF MILK

when it was this was for the purpose of‘enriching other foods in
cooking. We are told it was stored in a melted condition, and
was never eaten when fresh.

In the early methods of making butter, churning was brought
about by agitation of whole milk. In our own country at the
present time, in some of the Southern States, the method of churn-
ing whole milk rather than cream is still followed by farmers’
wives. Some difference of opinion exists as to the early methods
used for creating agitation sufficiently to gather butter from the
milk. Such methods were used as placing the milk in earthen
vessels and beating it with the hands until butter formed.
Later, wooden stirring sticks were used for the purpose of creating
agitation. ‘The Arabs churned their milk by placing it in leather
bags and dragging them over the ground by means of a rope
attached to a horse’s saddle. Another method used was that of
placing the milk in skin bags, fastening them to a tree and
swinging them back and forth to bring about agitation. (See
cut, Chapter XVII.) As time passed, more complete devices
or methods were adopted for churning, such as the dash churn.
Following the dash churn came the square box churn—which was
used extensively in creameries about twenty years ago—and the
table butter worker. Now we have the modern up-to-date
combined churn. Setting milk in cold water and permitting
the cream to rise lessened the time of churning and brought the
manufacture of butter down to a science.

The adoption of the centrifugal machine for separating
the fat from the milk was one of the greatest advancements in
butter-making. (See cut of first centrifugal machine in Chap-
ter XII.) The first centrifugal cream separator used in lowa—
possibly the first used in America—was a power separator which
Jeppe Slipsgaard brought with him from Denmark in 1882, and
which was used in a Danish community near Cedar Falls, in
Black Hawk County. It is worthy of note that this machine
was so novel to the customs officers in New York that they held it
for two months before they could decide as to whether it was
constructed of iron or steel. They finally decided that it was of
steel construction and fixed the duty at $93.

DEFINITION 3

Marked improvements have been made in the manufacture
of butter by the adoption of scientific methods and the use of
modern equipments. Changes have been made in the period of
lactation. Formerly the cow furnished milk only for her young.
Through the efforts of man, by breeding and selecting, the period
of lactation has been lengthened until at the present time it
extends over a period of ten months. The cow at the present
time is recognized as one of the most economical producers of
human food, hence, dairying has advanced rapidly in all coun-
tries that are adapted for the production of forage plants that are
suitable for feeding the cow.

The United States at the present time produces five times as
much butter as any other country. The late census estimates
863,577,000 pounds of factory butter manufactured in agus and
675,000,000 pounds of farm butter.

Notwithstanding the number of years that butter, milk and
other dairy products have been used for food, it is less than ten
years since the physiologists discovered that butter and milk
contained certain food elements that are essential for the growth
of the young that had escaped investigations made by eminent
chemists. This discovery was brought about by feeding experi-
ments by such noted physiologists as Dr. F. G. Hopkins of Cam-
bridge University, England, and Dr. E. V. McCollum of Johns
Hopkins University in this country. The discoveries made by
these eminent authorities will no doubt be the means of creating a
greater demand for dairy products of all kinds.

Definition.—Normal milk is a liquid secreted in special glands
cf all females belonging to the mammalian group. It is composed
chiefly of water, proteids, fats, sugar, and minerals. Coloring-
matters and gases and some organic acids are found in small
quantities.

All normal milk from the camer classes of animals, such as
mare, buffalo, goat, ewe, ass, and cow, has a general resemblance
in that it all contains water, fat, proteids, sugar, and ash. But
milk from different animals varies in the relative proportions of
its constituents. The chemical and physical properties are not
alike. When human milk is treated with half its volume of

t BUTTER-MAKING AND COMPOSITION OF MILK

ammonium hydrate and kept at a temperature of 60° C. for
about twenty minutes, it assumes an intense red color. Cow’s
milk turns faintly yellow if treated in the same way. This test
was reported by Unikoff, of St. Petersburg (now Petrograd), at
the meeting of the Medical Section, Royal Academy of Med-
icine, in Ireland. The various kinds of milk also differ from
each other in their behavior towards rennet. Richmond has
divided milk into two classes: Class I includes milk from the
ewe, buffalo, goat, and cow. When rennet is added to the
milk from these animals, the casein coagulates into a firm curd.
Class II includes human milk, milk of the ass, and mare.
When rennet is added to the milk of these animals, a soft curd
or none at all is formed. ‘The latter class seems to include the
animals without horns, while the first includes those with horns.

As the cow’s milk is used as a food to a greater extent than
that of any other animal, it has been subjected to more extended
and more careful investigation, and, as a consequence, more
definite knowledge has been obtained concerning its composition,
properties, and uses. The succeeding discussions have reference
to cow’s milk, if not otherwise stated.

Composition of Milk.—It is impossible to get accurate figures
on the composition of milk, as each of the milk constituents is
subject to fluctuation from various conditions, such as individ-
uality of cow, breed, season of the year, stage of lactation, milking
and environment.

The average composition, as determined by 280,000 analyses
reported by Richmond is as follows:

Wictteree 4 34 MAR ee ore pee 87.35
Fae Re i Oe oO eae a Bais
Vise SU ay a7: aoe eee 4.70
Breede | Casemn! "oar 3.00

AMMOTWHANEM, BUC. 5 oc 6 oo v 45
UNS eee eam cect 75

The composition of various kinds of milk is given by KGnig as
follows:

VARIATION OF TOTAL SOLIDS 5)

No. of Casein : ‘
Analy- | Water | Fat jand Al- Me Ash SPSCIHe
sugar Gravity
ses bumen
EMU ets = atte ore Toy || tN7foZzlae |) Bags 2.20 6.21 .31 1.0270
Mares pieces otras 50 QO. 78 | u.Qu 1.99 5.67 35 1.0347
Butialov. ce vae cise 8 || Ga.25 || 7.5 SO || AA 75 1.0350
JSS 2 ane ain eel ene en 7 | SO.04 | 2.02 || 2.22 | §.00 51 1.0345
(COS eae eter atere saree 793 | 87.17 | 3.60 | 3.55 | 4.88 71 1.0316
Wives 5 RA hod see ee 32 80.82 | 6.86 6.52 4.91 89 1.0341
(Goateany eke eaaacsha 38 85.71 | 4.78 As D 4.46 .76 1.0328
SOW PRC Cheeta carrie 8 | 84.04 | 4.55 Wo DB B02 I.05 1.038
Bitchemete ected | doce Ay |) Waa | OoSy7 luwsuy |) 8.60 AS 1.035
Elephanteys sae eaeeee 8 79.30 | 9.10 RQ, sit 8.59 50 1.0313
Hippopotamus....... I OQO.AZ | AG | conse 4.40 Il
Gamnele Sere So sacicce cts 3 86.57 | 3.07 4 5-59 77 1.042
IEVAIN ARR setae Se 3 86.55 | 3-15 3.90 | 5.60 80 T.034

Variation of Total Solids.—As applied to milk, “ Total
Solids,” is a term that includes fat, casein, albumen, sugar,
and ash; in other words, all the milk constituents except the
water. “Solids Not Fat” is a term often used, and includes
the casein, albumen, sugar, and ash, or all the milk constituents
except water and fat. “‘ Serum ” is a term used to designate all
the milk constituents except the fat. The fat is the most val-
uable constituent of the total solids. The variation in the total
solids of milk during the summer months is shown in the table
quoted below from Dr. Van Slyke of Geneva, New York:

Per Cent | Per Cent of

Mouth of Water | Total Solids
IMac. sah shavers ganas Sanches 87.44 12.56
SUING S ites Sais diherw oe ee eeonenel eect 87.31 12.69
TRON oR RN, Seine oes gles oo 87.52 12.48
PNUPUISU. 5 cas. 1st ce Saye a octane 87.37 12.63
September... sone soe ee 87 13
October c ss 54 2 eee 86.55 13.45

Dr. Van Slyke also studied the effect of the lactation period
upon the total solids in milk. A herd of fifty cows, calving in

6 BUTTER-MAKING AND COMPOSITION OF MILK

different months of the year, was used in the experiment. The
per cent of total solids of this herd seems to average a little high
all through the ten months. The total solids were found to be
14 per cent during the first month, decreasing to 13.47 per cent
during the next two months, then gradually increasing with the
advance of the lactation period. In the tenth month the average
total solids was 14.83 per cent. Pingree, of Pennsylvania, reports
having found normal milk from a cow which contained 17.01
per cent total solids. Sherman! reports a very high average
total of the milk solids. He treated the milk from thirteen cows,
and found it to contain on an average 18.03 per cent of total
solids. K®6nig reports a minimum of total solids of 9.31 per cent,
a maximum of 19.68 per cent, and an average of 12.83 per cent.
The average total solids quoted above from Richmond is 12.65
per cent, which agrees closely with K6nig’s results.

The difference in total solids of milk from some of the leading
breeds has also been studied by Dr. Van Slyke, and the results
are as follows:

Per Cent | Per Cent of

Bees of Water | Total Solids
olsteings merits: os seen 88.20 11.80
A yEShire spa ia cieveso essere 87.25 12) 75;
Shorthornaieasauccme series. 85.70 T4.30
WDC VOM Sena Seis w ecu isesenete 85.50 14.50
Guernse ye). 4) os seine sats Sotelenece 85.10 14.90
WErSeyctinn icon woven eee startet: 84.60 15.40

The maximum and minimum amounts of total solids men-
tioned above are abnormal cases. The normal variations of
the solids in milk are within comparatively narrow limits. For
this reason the minimum standard for total milk solids, in States
where dairy laws are in force, is fixed by law. Usually 12 per
cent is the minimum.

Water.—From what has been said above concerning the total
milk solids, it will be seen that water constitutes by far the largest

1 Jour. Am. Chem. Soc.

WATER 7

portion of milk. It is quite uniform, and in milk from a mixed
herd the water seldom falls below 86 per cent and seldom exceeds
88 per cent. Variations ranging from a little less than 80 per cent
to a trifle over 90 per cent are on record. But such variations
must be looked upon as occurring in only a very few special cases.

It has often been asserted that cows in the spring of the year,
when they are pasturing on new grass, or feeding on other suc-
culent foods, yield milk which contains an excess of water. Under
such conditions there is a tendency for cows to produce milk with
a water content a trifle higher, as has already been shown by the
figures quoted from Dr. Van Slyke. Asa rule this is much over-
estimated. It is even a common occurrence to hear creamery
operators say that their “ soft ” or “slushy ” butter, in the early
spring, is due to the excess of water present in the milk. This
particular phase will be discussed further under the heading of
“ Fat in Milk.”

The following question has often been raised: Is the water in
milk the same, \or any more valuable than water obtained from
other natural sources? ‘The water in milk, so far as known, is
transuded from the blood-vessels in the udder into the milk
glands. It is so perfectly mixed with the other milk constituents,
and holds the milk solids in such perfect emulsion and solution
that it would seemingly be impossible to prepare milk so per-
fectly by artificial means. However, a substance is prepared by
Jacob C. Van Marken, Neuweid, Germany, which, when added
to water, produces a substance similar in appearance to watered
skimmed milk. The preparation is named “ Kalberrahm Vita.”
The first name literally means calf-cream. It has a syrupy
consistency, and in appearance resembles light-brownish molasses.
It is sold in tin cans, and recommended highly for calf feeding
when mixed with skimmed milk. When mixed with water, it is
recommended highly for hog-feeding.

Water distilled from milk has the same appearance as ordi-
nary distilled water. It is clear and colorless. The chemical
reaction when phenolphthalein is used as an indicator is neutral,
as is that of ordinary distilled water, even when distilled from
milk in which acid has developed. But there is a considerable

8 BUTTER-MAKING AND COMPOSITION OF MILK

difference in the taste and smell. This indicates that some of
the volatile substances are distilled over with the water. The
probability is that these flavoring substances are so closely asso-
ciated with water in milk that they are inseparable, and that the
only place where this water can be prepared so as to assume these
qualities is in the cow’s udder. The conclusion would then be
that the water in normal cow’s milk cannot be distilled and
replaced by natural water without the loss of the normal good
flavor of the product.

FAT IN MILK

This is by far the most important constituent of milk, espe-
cially to creamery operators. It exists in the milk in suspension,
in the form of globules so small as to be invisible to the naked eye.
Fat globules, at ordinary living-room temperature, are present in
milk in a liquid form. Cooling the milk to a very low tempera-
ture (about 50° F.) hardens them. When the globules are caused
to unite, as in churning, they also solidify.

The size of the fat-globules is very minute, and varies con-
siderably, according to breeds, individual cows, and the stage
in the lactation period. The globules in the milk from the same
cow also vary a great deal. Lloyd found fat-globules in Jersey
milk to be from 8 to 12 micro-millimeters in diameter. Very few
were less than 4 micro-millimeters (a micro-millimeter is zo'so
millimeter, or zso00 Of aninch). The majority of the fat-globules
in milk from Shorthorn cows measured from 6 to 8 micro-
millimeters in diameter. According to Fleischmann, the size of
fat-globules varies between 1.6 micro-millimeters and to micro-
millimeters in diameter. A Danish investigator maintains that
the diameter of fat-globules is between .0063 and .coo14 milli-
meter, and that x cubic centimeter of milk contains from 2.6 to
11.7 million globules. He also asserts that a reflection of the
light renders it very difficult to get the proper size of the fat-
globules, as the light tends to make the globules appear larger
than they are in reality.

It has been maintained by some that the larger fat-globules
contain fats which are different from those contained in the

FAT IN MILK 9

smaller globules. But this is by some investigators considered
to be a matter of conjecture. Most authorities now believe

a. Skim milk.

Fic. 1.—Microscopical appearance of different kinds of milk. Magnified 300
times. (U.S. Farmers’ Bul. No. 42.)

that there is no difference in the kinds of fat of the different-sized
globules, even though some experiments ' show that fat composed

1 Gembloux, Belgium, Creamery Jour., London, No. 8, Vol. I.

10 BUTTER-MAKING AND COMPOSITION OF MILK

of larger globules has a finer flavor, and a little more oily appear-
ance.

From what has been said, it will be seen that the minute-
ness of the fat-globules is almost inconceivable. They were
first discovered in 1697 by A. von Leeuwenhoek. The minute
state of division, or the form of emulsion in which they exist
in milk, renders it easy to digest when consumed as a food.

Properties of Fat.—The specific gravity of pure butter-fat
at 15° C. is .93002. The refractive index of butter-fat at 22° C. is
on an average 1.459. The melting-point of pure butter-fat, as
now determined, varies between 32° and 37° C. (90° F. and
99 F.)

When pure butter-fat is rapidly cooled, it solidifies into one
solid mass; but if allowed to cool gradually, part of it solidifies,
and part of it remains a liquid longer than other parts. This
seems to indicate that some fats with a high melting-point sepa-
rate out from the fats with a low melting-point. This behavior
of pure butter-fat is not well understood, as it contradicts the
now accepted theory that the different fats are in chemical com-
bination with each other, rather than a mechanical mixture of
different glycerides of fat.

Glycerides of Fat——By this term: we understand that the
fatty acid radicals are in chemical combination with the glycerol
(glycerine) radical, thus:

| Fatty acid radicals.
Glycerol radical. C4H7O2 (Butyric)
C3sHs CisH3302 (Oleic)
-CisH35O2 (Stearic)

The chemical formula for glycerine is:

Hydroxyl groups.

Glycerol radical. [ OH
CsHs5 OH
OH

The difference and similarity of these two formulas are
easily observed, and the reason why the term “ Glyceride of Fat ”
has been applied to such a compound is evident.

CONDITION OF FAT 11

Condition of Fat.—Whether the fats in milk exist in chemical
combination, or whether they exist as glyceride of butyrin,
stearin, olein, etc., in the form of a mechanical mixture, is a
question in dispute. If they exist in the latter form, the composi-
tion of the different fats must be as follows:

Butyrin. Olein. Stearin.
{ C4H7O2 { CisH33O2 CisH 3502
CsHs5 | C4H7O2 C3Hs ) CisH3302 C3Hs CisH35O2,etc.
C4H7O2 CisH3302 CisH3502

and the total fat made up of a mechanical mixture of these and
the remainder of the fats in butter-fat.

Richmond and other authors believe that fat probably exists
in milk chemically, as first mentioned and illustrated; because,
if the fat were a mixture of glycerine tributyrate with other
glycerides of fat, butyrin or glycerol tributyrate could be dis-
solved out by the use of alcohol. But this is not thecase. More-
over, if butyrin existed separately in milk, it would be possible
to distill it off under reduced pressure. This cannot be done.

Theory in Regard to Films Enveloping Fat-globules.—The
extreme minuteness of the fat-globules in milk renders it almost
impossible to determine by direct microscopical observation
whether there is a membrane around each globule or not. Fleisch-
mann and Lloyd assert that, so far as they were able to detect,
there is no real membrane surrounding each globule.

The theory generally accepted in the past was that the film
surrounding the fat-globules was simply due to surface tension,
or to the fact that the molecules of the fat have a greater attrac-
tion for themselves than they have for the molecules of the serum
in which they are held in suspension. In support of this two
arguments are advanced.

(1) The natural milk-fat may be removed from milk and
artificial fat substituted in its place. The resultant milk has
characteristics similar to milk containing normal fat, that is, the
emulsion which milk forms with the artificial fat is apparently
like that formed with the natural fat.

(2) If there were a special albuminous membrane around

12 BUTTER-MAKING AND COMPOSITION OF MILK

each fat-globule, cream should contain a higher percentage of
albuminoids than milk. ‘This, Richmond maintains, is not so.

Dr. Storch concludes from extensive researches that there is a
gelatinous membrane enveloping the fat-globules. His conclu-
sions are based mainly upon the first three reasons given below.
The other facts mentioned also support his conclusions:

(1) When milk has been stained with ammoniacal picro-
carmine, and the cream washed with water until it is free from
milk-sugar, a stained layer is present around each globule.

(2) He has succeeded in isolating this gelatinous substance
from cream and butter. Owing to its existence in these two
substances, he assumes that it is also present in milk.

(3) When ether is added to milk, the fat-globules dissolve
with difficulty, unless some alkali is added to the milk first.

(4) Bichamp maintains that when ether is added to milk
the fat-globules are enlarged due to the ether passing through the
supposed membrane by the process of osmosis. He considers
this fact sufficient to prove that there is a membrane encircling
each globule.

(5) Butter containing 85 to 86 per cent fat is asserted by
Richmond to have the same consistency as cream containing
about 72 per cent fat at the same temperature. The solidity of
butter is due to the close proximity of the fat-globules. Now, if
cream with less fat has the same consistency as butter, the prox-
imity of the fat-globules must be equal to that of the butter;
this would indicate that there is a membrane and that this mem-
brane increases the size of the fat-globules.

(6) The fact that cream separated by centrifugal force is
more easily churned than cream of the same richness separated
by gravity methods, would also be explained if the fat-globules in
milk had such a membrane surrounding them.

This membrane, or what is believed to be a membrane,
Storch has isolated and analyzed. He finds it to consist of |
94 per cent of water and 6 per cent of proteid.

The reasons deduced by Storch are strong; and the behavior
of cream and butter renders it probable that there is such a
membrane enveloping each globule of fat.

CLASSES OF FATS 1185

CLASSES OF FATS

There are two great classes or groups of fats present in the
butter, namely:

(x) Volatile and Soluble,

(2) Non-volatile and Insoluble.

It was previously stated that little is known concerning the
way in which the fatty acids are combined with glycerine in the
milk; but, for the sake of convenience, the fats will be referred
to as if they existed as separate glycerides of fat.

The terms “ Volatile’ and “ Non-volatile”’ are applied to
the glycerides of fat, or to the fats as they exist in butter. Strictly
speaking, this is not proper, as they do not assume the volatile
characteristics until the glycerine separates from the fatty acids;
it is only then that the latter become volatile.

Volatile Fats.—The first group, or the volatile fats, include
butyrin, caproin, caprylin, caprin, and laurin. Butyrin is the
one present in the largest proportion. Laurin and caprin are
partially non-volatile. Butyrin is the most important fat
belonging to the volatile group. It is the most important quan-
titatively and also qualitatively. So far as is known, butyrin
is the least stable of any of the butter-fats. Under normal con-
ditions, so long as the fatty acid remains in combination with the
glycerol, it is neither volatile nor soluble in water; but as soon
as separation takes place, due to the action of micro-organisms,
or to the effect of light and air, it becomes volatile, and escapes
in the form of gas.

It is also claimed that these volatile fats have the special
properties of absorbing odors and gases to a greater extent than
any of the other fats. This absorption takes place when fat
comes into contact with the undesirable taints. For this reason
it is essential that milk, cream or butter be kept away from any
foreign, undesirable odors. These taints may also be imparted
to the fat before the milk is drawn. If the cow is fed on unde-
sirable food, such as turnips, onions, garlic, etc., the milk from the
cow assumes undesirable characteristic flavors which can easily be
recognized in the finished product. On the other hand, such

14 BUTTER-MAKING AND COMPOSITION OF MILK

foods as well-cured clover hay and bran seem to impart desirable
flavors to milk and butter.

The presence of these volatile fats in butter is quite uniform,
and is a distinguishing feature of pure butter-fat. The detection
of adulteration of butter with foreign fats is based chiefly upon
the presence of these volatile fats. “The characteristic desirable
flavor of butter is also believed to be due to the presence of the
volatile fats. The volatile fats vary but slightly during the dif-
ferent seasons of the year. They are present in the greatest
proportion during the spring and early summer months, when
cows are fed on grass, and also during the early stage of the period
of lactation. They decrease gradually as the lactation period
advances.

Volatile fats comprise about 8 per cent of the total fats in
milk.

Non-volatile Fats.—This group constitutes about 92 per cent
of the total fats in butter. Chemists now agree that palmitin,
stearin, olein, and myristin are the most important ones to be
considered, as will be seen from the table quoted from Richmond.

These non-volatile fats are of special importance, as the
relative amount of each of these fats largely causes the variation
in the hardness and softness of the butter and butter-fat. The
melting-point of these different fats varies according to the dif-
ferent investigators: olein is a liquid at ordinary temperatures and
melts at about 41° F.; stearin, on the other hand, has a melting-
point of about 150° F.; palmitin also has a high melting-point,
namely, about 142° F.; myristin melts at about 129° F.

Olein has been found to be present in the greatest propor-
tion during the spring, when cows are fed on grass. When
cows are fed on normal dry food, as in the winter time, it is present
in a much less degree. This, together with the small increase of
volatile fats, is the cause of the softer butter so frequent in the
spring. The hardness of the butter in the fall or winter is due
chiefly to the presence of a slightly increased amount of the fats,
with a high melting-point, as mentioned above.

From what has been said above, one is led to believe that,
by melting a sample of butter which contains these different

COMPOSITION OF BUTTER-FAT 15

fats, the fats with a low melting-point would melt first, and leave
the remainder in an unmelted condition. Such is not the case.
Butter-fat in this respect behaves a good deal like different
metals with different fusing-points. When they are melted and
mixed together, cooled and then remelted they assume a common
melting-point. Butter-fat behaves in the same way. It melts
at a temperature of gt° to 96° F.

As the body temperature of cows (about tor° F.) is above this
temperature, the fat globules are present in the milk in liquid
form when it is first drawn. A peculiarity about these fat-
globules in milk is that the milk and fat may be cooled below the
melting-point of the fat of butter without the fat-globules in milk
being solidified. It requires a temperature of between 60° and
78° F. before the fat-globules in milk begin to solidify. When
these small fat-globules are caused to unite, as during the churning
process, they solidify at a higher temperature. This behavior of
the fat in milk evidently must be due to a relative change in the
position of the molecules of fat during the process of cooling and |
warming. No definite explanations, so far as is nO, have been
given for this condition of the fat.

The non-volatile fats found in butter-fat are practically the
same as those found in other animal fats.

Composition of Butter-fat.——In his ‘“ Dairy Chemistry,”
Richmond gives the following composition of butter-fat, repre-
senting the mean results obtained by different observers:

Per Cent
BWV Ri A aes ete Nis aches tes 3.85
(8 per cent volatile.......... Garou een te eee ie te 3.60
Caroryliinies se mia a Aeneas 355
Rates ach (Gey Oighaly ater arctan ay eared oe tene? 1.9
[aia ee sates Rite eal Foul
ee,
Stearine arabe werys - Sect ae 1.8
s leit aren nay we ereny eter ty 35

Richmond also gives the percentage of glycerine and fatty
acids in each of the different fats, as follows:

16 BUTTER-MAKING AND COMPOSITION OF MILK

Biuey anit eee 3.85% yielding 3.43% fatty acids and 1.17% glycerine
Capron eee 3.60 yielding 3.25 fatty acids and .86 glycerine
Capnylineea seen .55 yielding .51 #4fatty acids and 10 glycerine
Caprime osF tees ee 1.9 yielding 1.77 fatty acids and .31 glycerine
Tbaurin’ av enea 7.4 yielding 6.94 fatty acids and 1.07 glycerine
IMDS, so ou ceo ae 20.2 yielding 19.14 fatty acids and 2.53 glycerine
Rallmniiinee eee Det) yielding 24.48 fatty acids and 2.91 glycerine
Stearn eeerior 1.8 yielding 1.72 fatty acids and .1g _ glycerine
Oleiniey es oa 35 yielding 33.60 fatty acids and 3.39 _ glycerine
100 94.84 12.53

PROTEIDS (ALBUMINOIDS)

The proteids of milk are present partly in solution and
partly in suspension. They are present in a very complex
chemical form. Some of the chemists reckon as many as eight
different albuminoids or proteids in milk. Duclaux claims that
there are only two kinds of albuminoids, the coagulable and non-
coagulable casein. He has, by the use of a fine filter, been able to
separate the fat and the coagulable from the rest of the serum.
The amount of coagulable casein is claimed to vary considerably,
and seems to depend upon the amount of lime phosphate present.
The filtrate which Duclaux obtained from filtering the milk was
clear and colorless, which proves that the removal of the casein
was quite complete. In order to remove casein from milk, a
special filter (Chamberland) is employed. Owing to this fact,
we may consider the casein to be present in suspension or semi-
solution. Noted chemists, such as Babcock, Van Slyke, Duclaux,
Storch, Hammarsten, Ritthausen, and Richmond, disagree upon
the number of albuminoid substances found in milk, and upon the
chemical behavior of each.

For all practical purposes it is safe to mention two, namely,
(rz) casein, and (2) albumen. Those two substances, as all agree,
are present in milk, and constitute practically all the albuminoids
in milk. But after these two have been separated from milk a
slight precipitation can be obtained by treating the filtrate with
alcohol. This has been called albumose and also lactoglobulin.
From this resultant filtrate a very small amount of material
containing nitrogen can again be separated. Dr. Babcock

CASEIN 17

has obtained a substance from milk called fibrin. These
latter substances, however, are present in minute portions, and
are believed by some of the best scientists to be the same as the
albumen. Their presence in the filtrate is due to incomplete
precipitation of the albumen in the first place.

Casein.—Casein is by far the most important of all of the
albuminoids. It is the substance which forms the curd in cheese-
making. In fresh milk, as is now understood, it is in chemical
combination with lime salts. It is on this account that fresh milk
shows the amphoteric reaction, which will be explained under
the “ Properties of Milk.” The coagulation of casein by the
addition of rennet or dilute acids is thought to be due to this
union between the casein and lime. Fleischmann refers to this
as the “‘ caseous maiter”’ of milk. The viscosity of normal milk
is believed to be due in a large measure to this condition of casein
in milk. It causes the casein to be present in a colloidal condi-
tion. When milk coagulates by natural or by artificial means,
the union between the casein and lime phosphate is largely
broken.

Casein and albumen differ in composition, in that the casein
contains phsophorus and less sulphur than does albumen.
Fleischmann maintains that a substance called nuclein is asso-
ciated with casein, and is not found in albumen. .

Casein is precipitated by the use of rennet and dilute acids,
and coagulates spontaneously, due to the acid formed in the milk.
The precipitates formed by the use of different precipitating
agents are not alike. The curd coagulated by rennet contains
more fat and calcium phosphate than the curd which is precip-
itated by dilute acid or by the spontaneous souring of the milk. If
milk stands at air temperature for any length of time after milk-
ing, the caseous matter (or the nitrogenous matter combined with
lime) tends to separate. The caseous matter of milk is not com-
pletely precipitated by heat, although heat partially destroys the
union between the casein and lime. This largely destroys the
action of rennet. Instead of getting a smooth solid coagulum, a
more flaky precipitate is obtained. For this reason milk for
cheese-making should not be heated to a high temperature. By

18 BUTTER-MAKING AND COMPOSITION OF MILK

heating milk in a glass flask to a high temperature, and letting it
stand for a time, it will be found that a mineral precipitate has
settled to the bottom. This precipitate is believed to be a lime
phosphate, which, previous to heating, was combined with the
casein of the milk. By adding calcium chloride (CaClz) to milk
which has been heated, its normal condition towards the action of
rennet is again restored.

Albumen.—lIf the casein is removed from the milk by pre-
cipitation, and then filtered off, the filtrate will contain a sub-
stance which will precipitate when boiled. This is albumen,
and is similar in character to albumen from the white of an
egg. It differs from casein in that it is not precipitated by
rennet or acids, but precipitates on heating. It does not contain
any phosphates, but contains a comparatively large amount of
sulphur.

As the albumen is soluble in rennet and dilute acids, it can
readily be seen that it is retained in the whey obtained in cheese-
making. When albumen is present in small quantities, as it is in
normal milk, heating does not completely precipitate it, unless
the casein or curd is first removed. If, on the other hand,
albumen is present in excess, as is the case in colostrum, the major
portion of the albumen is precipitated when heat is applied with-
out first removing the casein.

Sugar.—Milk-sugar occurs in milk to the extent of about 5
per cent. It varies very little in quantity, seldom falling below
3% per cent and seldom rising above 5% per cent. It occurs in
solution, and is not found elsewhere in nature.

Milk-sugar is the most unstable component of milk; its
decomposition is brought about quickly and easily by the action
of micro-organisms. If these could be entirely excluded from the
milk, it would keep for an almost indefinite length of time. As it
is impossible under practical conditions to entirely exclude
organisms from the milk, the only way to retard and prevent the
growth of germs and thereby prevent the changing of the sugar
into other products, is to cool the milk to a low temperature
(so° F.), or to heat the milk to a sufficiently high temperature
(180° F.) to destroy most of the germs. According to Van Slyke

ASH 19

and Hart, the decomposition of the caseous matter produces free
casein. When about .5 per cent acid has developed in the milk,
the free casein combines with the acid and forms casein lactate.
The chemical composition of milk-sugar is Ci2H2201:+H20.
Were a perfect decomposition of milk-sugar into lactic acid to
take place, the following equation would represent the change:

(Milk-sugar) (Lactic acid)
Cy2H 24012 = 4C3H6QOs.

Such an ideal change, however, never takes place. In such a
case, one gram of milk-sugar should produce one gram of lactic
acid. In a number of experiments carried on by one of the
authors of ‘‘ The Analysis of Cream during Different Ripening
Stages,’ the highest amount of acid produced from one gram of
milk-sugar was .8 of a gram. This indicates that there are
always accompanying by-products produced, besides lactic
acid, when milk-sugar is being decomposed in cream or milk.
The sourness of milk is due to this change. The by-products
which accompany the production of lactic acid are many
and various. The most important ones are gases of different
kinds, such as carbonic acid gas (COz); marsh gas (CHa,);
hydrogen (H); and nitrogen (N.) Small amounts of alcohol,
formic, acetic, and succinic acids are said to be normal
accompanying by-products also. These by-products may also
partially result from the breaking down of some of the other milk
components.

As milk-sugar is in perfect solution, it follows the water of
milk, and in cheese-making nearly all of it passes into the
whey. Commercially and chemically it is prepared from whey.
It is a white, not very sweet powder, and is used for medicinal
purposes to dilute pure, powerful drugs. It is also used exten-
sively in the preparation of modified milk.

Ash.—The ash of milk is present in very small quantities,
and when viewed from such a standpoint it may first seem to be of
small importance. On account of the effect of the mineral con-

1 Thesis, I. S. C., Ames, Ia.

20 BUTTER-MAKING AND COMPOSITION OF MILK

stituents upon the properties of milk, it is one of the most impor-
tant components of the milk. It exists partly in solution, and
partly in suspension. Babcock maintains that about one-third
of the usual ash constituents are in suspension, and that they
consist chiefly of lime phosphate.

All of the minerals in milk consist chiefly of potash, lime,
soda, magnesia, and iron, combined with phosphoric, hydro-
chloric, sulphuric, and carbonic acid. Calcium phosphate
constitutes about one-half of all the ash constituents. They
are named above, in order, according to the extent to which
they occur in milk.

Gases of Milk.—These do not normally exist in milk to such
an extent as to enable chemists to determine them quantita-
tively, but they are of great importance, owing to the effect they
have upon the quality of the milk, viewed in the commercial
sense.

Gases in milk may be divided into two classes according to
their origin; namely, (1) those imparted to milk before milking
and (2) those which are later formed and absorbed in milk.

(1) When freshly drawn, milk has a characteristic odor,
which seems to be normal to all fresh milk. The gases which
cause this odor are very volatile, and by cooling and stirring the
milk can, to a large extent, be eliminated. The amount and
kind of taints existing in milk, immediately after it has been
drawn, largely depend upon the food which the cow has been
fed. Turnips, onions, and garlic, when fed to cows a short time
before milking, cause undesirable gases or taints to exist in the
milk. Good hay, bran, and good grass produce milk of superior
quality, containing no odors excepting those which are natural to
all milk when first drawn.

The milk yielded by cows pasturing in the Alps of Switzer-
land is said by tourists to possess a peculiar, not undesirable,
spicy odor and flavor. It is maintained by the native people in
Switzerland that the peculiar flavor of the Emmenthaler cheese
cannot be developed anywhere else in the world. This flavor
they believe to be due to the kind of vegetation the cows feed
upon in the Alpine pastures. In Denmark, the poor people

GASES OF MILK il

who do not own much land, graze their cows along the roads
where weeds of different kinds grow. Milk from such cows has a
peculiar characteristic odor or taint. In this country it is a
common occurrence to find that milk delivered by patrons who
keep their cows on timber-land pastures has a peculiar weedy
odor. Especially is this true in the fall or late summer. If such
milk is heated to 160° to 180° F., and stirred occasionally, some of
these taints pass off. The addition of a small amount of saltpeter
will improve the flavor of milk where such foods as turnip and
sugar-beet tops are fed. This remedy is often applied to milk in
Canadian cheese factories, during the fall of the year when turnip
tops are fed, and also in Germany during the period of the feeding
of sugar-beet tops.

Too much emphasis cannot be placed upon the food that
the cows receive. While it is true that much of the desirable
aroma and flavor in butter is due to bacterial growth, the kind
of food fed to cows is not without significance. It is a well-known
fact that districts such as Normandy and Denmark, which have
become famous for their high quality of dairy products, have the
best of pasture and winter feeds.

Besides the kind of food, some physiological disturbances of
the cow may cause abnormal taints in milk.

(2) Gases or taints which are formed in the milk or absorbed
by it are due to fermentation and absorption respectively. The
former cause will be considered in a separate chapter, and the
latter cause needs little explanation. It is a well-known fact
that milk and most of its products have the special property
of absorbing odors which may be present in their surroundings.
For this reason, milk, as well as other dairy products, should at
all times be kept in clean utensils and pure surroundings.

Taints appearing in milk immediately after milking are due to
absorption within the cow. Taints that develop on standing are
due to bacterial growth in the milk, or to absorption from impure
surroundings. In the prevention and removal of taints from
milk the first step is to remove the cause, and the second to
eliminate as many of these taints as possible by a process of
aeration or pasteurization.

22 BUTTER-MAKING AND COMPOSITION OF MILK

Coloring-matter.—It is not known of what the coloring-
matter in milk consists. A substance named lactochrome has
been found in milk. So far as known, this coloring-substance is
closely associated with the fat called palmitin. The amount of
coloring-matter varies during the different seasons of the year.
It also varies according to the different breeds. During the
spring of the year, when cows are first put on grass, the color of
of the butter-fat is always higher than it is during the latter por-
tion of the summer. During the winter, the fat in milk is quite
pale. By feeding the cows some succulent feed in the winter,
such as silage, carrots, and beets, the color of the butter-fat is
rendered much higher.

From this it would seem that the change in the color of the
fat with the different seasons, and with the food given, is closely
associated with chlorophyl, the coloring-matter of grass.

Other Constituents of Milk.—It is said that constituents
such as citric acid, urea, nuclein, lecithin, and galactase are
present. Babcock maintains that he has discovered a sub-
stance named fibrin. This seems to be similar to the nuclein
mentioned by Fleischmann, if not the same. But as these
substances are present to a very small extent, citric acid, urea,
and fibrin being present to the extent of .12, .c07, and .coo2
per cent respectively (Fleischmann and Babcock), they are of
little importance.

CHAPTER II
MILK SECRETION

The Mammary Gland as a Secretory Organ.—The mammary
gland of females belonging to the order of mammalia secretes a
fluid known as milk. This substance is strictly a secretory
product. There are two kinds of glands present in the animal
body, viz., the excretory and the secretory. Generally speaking,
an excretory gland is one which receives or absorbs the waste
matter of the body, and causes it to be carried off without causing
any marked change to take place in the substance excreted.
A secretory gland is one in which the raw material is obtained
from the blood and then manufactured into a special different
product within the gland itself. As an example of a secretory
gland, the milk-gland of the cow’s udder is an apt illustration.
The glands in the mouth secreting saliva, and those in the walls of
the stomach secreting the digestive fluids, are also secretory
glands.

Internal Structure of Cow’s Udder.—The cow’s udder is
composed of two separate glands, the right and left halves.
These two glands are distinctly separated from each other by a
fibrous tissue running longitudinally. This fibrous partition
extends along the abdomen in front, and back to a point between
the thighs of the cow. It also serves to hold the cow’s udder in
place. There is no connection at all between the right and left
glands, and consequently milk cannot be drawn from the left
side over to the right, and vice versa.

Each of these right and left halves is again divided into two
parts, thus making the cow’s udder appear to be divided into
quarters. The cow’s udder may then be said to consist of two
glands, one on each side, and four “‘ quarters,” two to a gland.
The division between the two quarters of a gland is not complete;

23

24. MILK SECRETION

that is, there is enough connection between the two to allow
a portion of the milk to be drawn from the rear quarter through
the front teat on the same side, and vice versa.

The milk-glands proper are located near the abdomen and
extend a trifle downwards into the udder. The remainder of the

fix. pent pe 3
Se : “ te :

i
EAA

GLAND-LOBULE Khe

te

ALVEOLI

moe ARTERY
oom NERVE

I'Ic. 2.—Schematic figure showing cross-section of cow’s udder; and also
enlargement of epithelial cells in alveoli when cow is giving milk (1). Each
alveolus is surrounded with a membrane called tunica propria. Cell nuclei
not shown. When cow is in milk they are also enlarged. When not the
epithelial cells are Hat and the nuclei small and spindle shaped (2).

udder is filled with ducts, fibrous and connective tissue, muscle,
nerves, and blood-vessels, the whole udder assuming a sort of
spongy and open condition.

The teat is simply a cylindrical-shaped body, with a hollow
tube extending down through the center of it. At the bottom

INTERNAL STRUCTURE OF COW’S UDDER 25

of this opening, or at the end of the teat, there is a sphincter
muscle, which in some cases is drawn up very tight, while in
other instances it is so loose that it will not prevent the milk from
escaping. In case the muscle is so tight that the milk can be
drawn only with difficulty, it may be relaxed a trifle by inserting
a small, smooth wooden plug. This will usually dilate the open-
ing sufficiently, so that the milk may be drawn with comparative
ease. In some instances this muscle is so tight that it is necessary
to relax it by the use of a sharp knife. This, however, should be
done with surgical skill; otherwise the whole muscle is likely to be
so injured as to cause the milk to leak away at all times.

The upper part of this canal in the teat connects with what
is called the milk-reservoir. The size of this reservoir varies in
different cows. The average capacity of this miulk-cistern is
about one pint. The opening from this reservoir into the teat
is also guarded with a muscle. Over this muscle the cow has
little control; over the muscle at the lower end of the teat she
has no control whatever.

Opening into the sides and top of this reservoir are a large
number of tubes, which are called milk-ducts. These milk-ducts
extend from the reservoir up into the milk-gland. They radiate
in all directions, divide and subdivide, so as to form a very large
number of small tubes. These milk-ducts are surrounded with
fibrous muscular tissue, nerves, and blood-vessels. They are all
guarded by a special muscle at the junction with the main milk-
ducts, from which they radiate. These muscles are so inti-
mately connected with the nerves and muscular system of the
cow that she is able to open and close them at will. There are
very few cows that are not able to hold up their milk during
nervous and exciting periods. It is a common occurrence for a
milker to get only a small part of the milk from a cow; this small
amount is the portion which is present in the teat and milk-
reservoir. Some cows are able to hold up this milk also, but the
majority of cows cannot perfectly control the muscle which
guards the entrance to the teat. The milk which is present in
the milk-ducts and which has to pass through these junctions
referred to above can be held up by most cows at will.

26 MILK SECRETION

All of the small milk-ducts end in small sac-like bodies, each
of which is called a gland-lobule or ultimate follicle. The gland-
lobules enclose numerous individual microscopical bodies called
alveoli or acini; these are the organs which possess the proper
secretory functions. ‘Their outer covering is a membrane called
the tunica propria; within this there is an intermediate layer of
cell-tissue, and an inside layer composed of cells, which are named
the epithelial cells. These epithelial cells within the alveoli are
supplied with blood from the cow’s system. During lactation
they assume a different form, swelling and extending into the
cavity of the alveoli when the cow is yielding milk abundantly,
and when she is not in milk the alveoli are flat. A certain
number of alveoli are tributary to one particular duct leading
from the gland-lobule into still larger milk-ducts.

Each aggregation of gland-lobules, tributary to one milk-
cistern, constitutes a lobe, and may be likened to a side branch
of a bunch of grapes. Each separate grape may represent a
gland-lobule. ‘The seeds within the grape, if we imagine each
seed to be hollowed out and lined with small column-like bodies,
may be likened to the alveoli. These column-like bodies would
then represent the epithelial cells. ‘The stem leading from each
individual grape may represent the small duct which carries the
milk on to the larger ducts. The main stems of the bunch may
represent the larger ducts that enter into the milk-reservoir. The
air which everywhere fills the openings or interstices of the various
parts of the bunch of grapes may be likened to the fibrous fatty
tissue between the alveoli and the lobules of the gland.

Theories of Milk Secretion.—Although the theories of milk
secretion have been studied considerably, many things in this
connection are not well understood. Previous to the year
1840 it was thought that the only function of the milk-gland
was to filter the milk as it transuded from the blood. It was
supposed that the quality and quantity of milk depended entirely
upon the food. The theory has also been advanced that the
major portion of the milk constituents is a decomposition of
the product of the lymph bodies of the blood. It was believed
that the lymph bodies were a source of nourishment to the fetus.

THEORIES OF MILK SECRETION 27

and that the calf received its nourishment from the same source
after it was born as it did previous to birth. It was supposed that
after the birth of the calf the opening on the uterus through which
the food was supplied was closed, and that a new opening was
formed in the milk-gland. These two theories have now been
practically overthrown. It has been demonstrated that the
major portion of the milk is formed within the milk-gland. The
fat, casein, milk-sugar, and part of the albumen are supposed to
be formed in the udder. This conclusion is substantiated by the
fact that these substances do not appear in the blood, at least not
to such an extent as to warrant the assumption that they are not
manufactured in the cow’s udder. The total amount of fat in
the blood of the cow would not equal the fat in the milk from one
milking.

By some it is maintained that the substances in milk which
are found in solution may be transuded directly from the blood.
Here again milk-sugar is found to be in perfect solution in the
milk. But this substance can be found nowhere in nature
besides in milk. Itis not present in the blood of the animal;
consequently it must be manufactured within the gland itself.
The water of milk, and the ash constituents which are in solu-
tion, are probably transuded directly from the blood. No
attempts have been made to determine definitely how casein and
albumen are formed within the gland.

According to the theory which has been advanced, the fat is
formed by the breaking down of the epithelial cells. When the
breaking-down process is completed, the transformed cells appear
at the opening of the alveoli in the form of distinct fat-globules.
This is supposed to be the origin and formation of fat-globules
in milk; so it may be said that so far as known the fat is the
result of a breaking down of degenerated epithelial cells.

Dr. Bitting asserts that the formation of milk solids in the
cow’s udder is probably due to a metabolic process rather than
to a degenerative. Collier found that a cow giving a normal
amount of milk would secrete about 136,000,000 fat-globules
per second. He also suggests that a cow secretes about 5 pounds
of milk solids per day. As a cow’s udder weighs only about 23

28 MILK SECRETION

pounds, the whole udder would have to be renewed twice daily.
This is not consistent with our presint knowledge of tissue
building.

The chief incentive to milk secretion is maternity. As soon
as the young mammal is born the blood which went to the
uterus to supply the calf is turned toward the udder instead.

Fic. 3.—A schematic figure showing the course of the artery leading to the
mammary gland and the veins returning to the heart. The light-colored
lines represent arteries and the dark-colored lines the veins. (From Bitting,
Twelfth An. Report, Indiana.)

As soon as this current of blood begins to flow, all of the blood-
vessels and capillaries in the cow’s udder swell. This causes the
minute blood-vessels or capillaries which form a network in the
walls of the alveoli to swell, and their swelling stimulates the
epithelial cells to activity.

Conditions Affecting Secretion of Milk.—There are a great
many conditions which affect the milking capacity of a cow.
These conditions may be conveniently grouped into two classes

CONDITIONS AFFECTING SECRETION OF MILK 29

according to their causes: (1) conditions which are controlled
largely by man, and (2) conditions which are inherent in the cow.

t. Some of the chief conditions which reduce the secretion of
milk and are largely controlled by man are: improper care
and treatment of the cow, lack of proper food, incomplete and
and improper milking, irregularity, and long periods between
milkings. Pregnancy, nervousness, or excitement of any kind
affects the proper working of the milk-glands considerably.
These latter causes, however, are not always controlled by man.

2. Without denying the influence of those conditions men-
tioned above, the conditions which chiefly affect the milk-
secreting capacity are inherent. It does not matter how much
good care and food a cow receives, if she does not possess these
inherent necessary qualities. As was mentioned before, the
milk-secreting capacity depends upon the number of gland-
lobules, the amount of blood which is supplied to these secretory
paris, and the capacity of the cow to digest and assimilate food,
and possibly upon a stimulating body fluid not yet well under-
stood.

The number of gland-lobules is believed to increase until the
cow is about seven years old. The milk-secreting glands are
present only in a rudimentary form, until the cow has had
her first calf, or is well advanced in the first stage of pregnancy.
The gland-lobules then increase in number up to the age of about
seven. The relative number of lobules in the cow’s udder can
only be approximately ascertained. The size of the udder in
some measure indicates this. A cow with a large flexible udder is
usually a good milker, due to the fact that a large udder usually
contains a large number of gland-lobules.

The amount of blood which is turned through the cow’s udder
to supply the milk-secreting cells may be approximately ascer-
tained by the size of the blood vessels. The blood from the heart
- enters the udder near the region of the hips. It then passes down
through the udder, along the abdomen just beneath the skin,
until it reaches a point about midway between the flank and the
girth. At this place it penetrates the abdominal wall and enters
the thorax. The place at which the blood penetrates the abdom-

30 MILK SECRETION

inal wall may be felt with the finger. It is supposed that the
size of this hole is in some measure indicative of the milk-produc-
ing capacity of the cow. This opening in the abdominal wall is
called the milk-hole or milk-fountain. Large irregular veins are
considered a much better indication of good milking properties
than small straight veins.

The formation of gland-lobules is entirely inherent in the cow.
The only way that these may be increased is through selection
and breeding. ‘The amount of blood which passes through the
cow’s udder is also largely inherent, although this may in a small
measure be affected by the amount and quality of food given to
the cow. It should at all times be remembered that a cow is not
a mere receptacle into which so much food can be introduced, and
from which so much milk can be drawn. After giving due credit
for the influence of all other conditions, we must still recognize
that the inherent conditions affecting the secretion of milk are
the most important.

External Appearance of the Udder.—A cow’s udder should be
well and symmetrically formed. It should be square and wide,
and extend well along the abdomen of the cow, and back up
between the thighs. When the udder is empty it should be soft
and flexible. The teats should be medium large, be placed well
apart, and point downwards.

There should be little or no depression in the udder between
the teats; that is, each quarter should not appear distinct and
separate when viewed from the exterior.

The cow’s udder should be covered with fine, soft, downy
hair. A light golden yellow is said to be indicative of a good
quality of milk.

A firm, fleshy udder is undesirable. In the first place, it is
not indicative of good milking qualities, and, secondly, such
an udder is predisposed to inflammatory diseases.

Milk-fever.—This is a common disease in fresh cows. It is
due to a congested condition of the cow’s udder. ‘The decompo-
sition products of the colostrum milk in the udder are absorbed by
the blood, and produce the characteristic symptoms of milk-fever.
Dr. Peters, of the Nebraska Experiment Station, says that a good

MILK-FEVER 31

and simple remedy for a diseased udder is to pump it full of air.
This can be accomplished with an ordinary bicycle pump. After
some air has been pumped in, the cow’s udder should be worked or
massaged with the hand so as to cause the air to pass through
the quarter. He claims that the udder can thus be restored to its
normal condition very quickly, thereby preventing and even
curing milk-fever. In case the udder is caked very badly, apply a
hot poultice. Small five- or ten-pound bags filled with bran
and kept hot will prove very satisfactory. A compress consisting
simply of a piece of heavy cloth is also used. It should be put
on so that it lifts up the entire udder, and tied over the back of
the cow. Straw should be put underneath it on the back so that
the cord will not injure the animal.

CHARTER iit
PROPERTIES OF MILK

Color.—The coloring matter of milk is associated with the fat.
According to extensive investigations, made by Eckles and
Palmer at the Missouri Station, this color is due to carotin, so
called because it is the coloring matter of the carrot. It is found
in green plants and is closely associated with the chlorophyl,
which hides its presence. It is not manufactured by the animal.
Animals which produce milk rich in fat, in the form of large fat-
globules, possess the ability to utilize this coloring matter to a
greater degree than do animals which produce milk having a lower
fat content and smaller fat-globules. This explains the downward
gradation of the color of the fat in the milk as we pass from the
Guernsey and Jersey to the Shorthorn, Ayrshire and Holstein
breeds.

Flavor.—Milk has a sweet flavor, and a faint odor. Fresh
milk has a peculiar taste and odor, which pass off when it is
exposed to the air. The flavor is affected by foods and con-
ditions of the cow, as mentioned under “ Abnormal Milk.”

Opacity of Milk.—Milk is opaque, except when seen in very
thin layers; then it is shghtly transparent. The opacity of milk
is due to the presence of the fat and nitrogenous matter. When
these substances are filtered away on a fine clay filter (the Cham-
berland), the filtrate which passes through is clear and trans-
parent. It has been maintained that the fat in milk is the chief
cause of its opacity, and that the percentage of fat could be
determined according to the degree of opacity and transparency
of milk with an instrument named pioscope; but it was soon found
out that the size of the fat-globules, as well as the number, had
considerable influence upon the degree of opacity of milk. For
that reason, this method of determining the amount of fat in

32

CHEMICAL REACTION OF MILK 33

milk was not reliable. The fat-globules themselves are said to be
almost transparent, yet the color and opacity of milk is largely
due to their presence. This characteristic may perhaps be
explained by assuming that the fat-globules in milk deflect the
light instead of allowing it to pass through them.

After the fat has been removed, the milk still continues to
be opaque. When the albuminoid matter has been removed
and filtered off the filtrate becomes clear and transparent.

Chemical Reaction of Milk.—Milk when fresh shows an
amphoteric reaction, which means that it exhibits both an alkaline
and an acid reaction when tested with litmus paper. It turns
blue litmus paper red, and red litmus paper blue. This peculiar
behavior of milk is said to be due to the caseous matter in the
milk, which itself has an acid reaction, while the remainder of
the serum has a slight alkaline reaction. By testing the reaction
of fresh milk with a tenth normal alkali solution, and using
phenolphthalein as an indicator, an acid reaction is obtained.
After standing, milk soon becomes distinctly acid, due to a
change of the milk-sugar into acids, chiefly lactic acid, through
the action of micro-organisms. Richmond maintains that the
amphoteric reaction of milk has acquired a false importance, as he
believes that the neutrality, as measured by the action of litmus
paper, is not chemical neutrality.

Specific Gravity of Milk.—By specific gravity of milk we
mean the weight of the milk as compared to that of an equal
volume of water at the same temperature. If a certain volume
of water weighs 1ooo pounds, an equal volume of milk at the
same temperature and under the same conditions will weigh
about 1032 pounds. Reducing the figure to a basis of 1, as is
always done, the comparison between the two equal volumes of
water and milk will be 1 and 1.032. This latter figure represents
the average specific gravity of normal milk.

It can be readily seen that the correct specific gravity can
be obtained only at one given temperature, for, as the tempera-
ture of the substance becomes higher, the density of it grows less,
and consequently the specific gravity will be less. The tempera-
ture at which the lactometers are standardized is 60° F.

34 PROPERTIES OF MILK

The specific gravity of milk will also vary according to the
relative variation in amounts of the different components. Ifa
sample of milk is rich in solids not fat, as, for instance, skimmed
milk, the specific gravity will be high and usually between 1.033
and 1.037. Ifthe sample of milk is rich in fat, as, for instance, in
cream, the specific gravity will be less.

The specific gravity of milk islessened by the addition of
water. Owing to this fact it was first thought that adulteration
of milk with water could be detected by testing its specific grav-
ity. But this method was soon found to be erroneous, as it is
possible to take cream away and add water in such a proportion
as not to alter the specific gravity of the sample. A low specific
gravity may, however, cause the suspicion that the milk has
been adulterated, and the test for water adulteration can be
supplemented by testing it for fat.

As has been mentioned before, the lactometer reading should
be taken at 60° F. If the temperature of the milk is above or
below, corrections must be made. The amount of correction
which will give approximate results is .1 of a degree added to the
lactometer reading for every degree Fahrenheit of tempera-
ture above 60° F., and .1 of a degree subtracted from the lactom-
eter reading for every degree of temperature below 60° F. The
temperature of milk when tested for lactometer reading should
never go any lower than 10° below 60°, nor any higher than 10°
above 60°. This would leave the range of temperature between
Gs) enael Go) 18.

In chemical laboratories, the specific gravity of milk is usually
determined by the use of a picnometer.

In practice there are three instruments in general use for
determination of lactometer reading, or specific gravity, viz.,
Quevenne lactometer, New York Board of Health lactometer
and the ordinary hydrometer. The Quevenne lactometer is the
one that is used chiefly in creameries. The graduation of each
one of them is given in the accompanying diagram. It may be
seen from the figures that in order to change the Quevenne
lactometer reading into specific gravity, all that is necessary is
to add tooo and divide the sum by tooo. In changing the

NATURAL SEPARATION OF CREAM AND MILK 30

specific gravity into lactometer reading the reverse process will
give correct results.

The hydrometer gives the specific gravity directly. The
Board of Health lactometer has a special graduation. When
this lactometer was devised it was thought that 1.029 was the
minimum specific gravity of un-
adulterated milk. The scale on this
lactometer was made from zero
to 120, zero marking the point which
represents the specific gravity of
water, namely, 1, while too is the
point which is assumed to represent
the least specific gravity of milk,
1.029. If the specific gravity of a
certain sample of milk fell to go, it
indicated that there was 1o per cent
of water present. If it fell to 80,
it indicated that there was 20 per
cent of water, etc.

In order to calculate the total
solids, and solids not fat, of milk,
it is necessary to know its lactometer
reading, and the percentage of fat
in it. Knowing these factors, by
the use of the following formula

: : Ss
given by Farrington and Woll, and ug» specific ee wate

deduced from Fleischmann’s work, “N” New York State.

5 : Q” Quevenne,
the total solids, and solids not fat, AA lars lk aidine

can be found. tion of lactometer stems.

Solids not fat = 7 lact. reading+.2 times the fat.
Total solids =fat-+solids not fat.

Natural Separation of Milk and Cream.—When milk is
allowed to stand quietly for a short time, a layer having a rich-
yellow color comes to the surface. This is the cream, and con-
tains most of the fat. This separation is due chiefly to the

36 PROPERTIES OF MILK

difference in weight, or specific gravity, of the fat-globules and
the serum. The force which acts upon the globule of fat is the
difference in weight between the fat-globule and the serum which
it displaces, minus the resistance with which it meets in its upward
passage. This force is great in milk with a high degree of vis-
cosity and slighter in milk of a limp and liquid consistency.

While the addition of water to milk reduces its viscosity it also
lowers its specific gravity. Hence, the so-called ‘“ ditution cream

Fic. 5.—Standardized milk. Showing the amount of cream on milk contaiiing
the designated per cent of butter-fat. (From Bul. g2, Ill.)

separator’ has, generally speaking, little to recommend it.
While the skim-milk may give a lower test we must remember
that there is a greater quantity of it. Furthermore, it lacks the
palatability and feeding value of undiluted skim-milk. But this
is a point that need not be labored, since the hand separator has
all but superseded the different methods of setting milk.

In normal milk, the amount of fat left in the skimmed milk by
natural creaming is about .4 per cent. The fat which is left in
this skimmed milk is largely composed of very small globules.
This is due to the fact that the resistant force on these small
globules is equal to or greater than the buoyant force acting upon
them.

ADHESION OF MILK 3:7/

The completeness of natural skimming is to a certain extent
based upon the mathematical law which is stated as follows:
“The surfaces of two spheres are to each other as the squares of
their diameters, and their cubical contents are to each other
as the cubes of their diameters.” The larger the globules are,
the greater the surface is, and the greater the resisting force to
which they are subjected. From the law stated it can be seen
that as the size of the globule increases, the cubical content
increases more rapidly than the surface. If a fat-globule were
split up into smaller ones, there would be more surface exposed
to the serum than was the case while the fat was present in one
globule.

For illustration, suppose two globules of fat to have diameters
of 4 and 2 inches respectively. The squares would be 16 inches
and 4 inches respectively; their cubes would be 64 inches and 8
inches respectively. It will thus be seen, according to the
law quoted above, that the larger globule has a surface only four
times as great as that of the smaller one; but the cubical content
of the larger globule is eight times that of the smaller one. This
illustrates why the large globules rise in cream more quickly than
the small ones. In this particular instance the upward force the
larger globule is subjected to is eight times greater than that of
the smaller one, while the resistant force is only four times as
great as that of the small one.

Adhesion of Milk.—Normal sweet milk adheres to wood,
glass, and metals to a greater extent than does water. Whole
milk has greater adhesive properties than skimmed milk. A
paper moistened with milk or cream makes a label that will stick
to any dry object; the same paper moistened with skimmed
milk has less adhesive power. The adhesive properties of milk
are also due to the condition of the nitrogenous matter. This
_ fact is made use of in painting and whitewashing. Slaked lime,
when mixed with buttermilk, or milk of any kind, gives a white-
wash which will remain on objects much longer than that made
by mixing with water.

Viscosity of Milk.—Milk is more viscous than water. The
degree of viscosity of fresh milk varies chiefly with the tempera-

38 PROPERTIES OF MILK

ture and fat content. So far as understood, the lower the tem-
perature, the greater the viscosity. Development of acid, and
high temperature lessen the viscosity of milk. Pasteurized milk
or cream is less viscous than the same milk or cream unpasteur-
ized. This lack of body can again be restored by adding a little
viscogen, as recommended by Babcock and Russell. It is not
advisable to use it, however, as it does not add materially to the
nutritive value of milk, but merely restores the body.

The great viscosity of thick cold cream makes it difficult to
churn, as most butter-makers have discovered. It adheres
to the inside of the churn and simply rotates instead of being
agitated. Cream that is cold and thick whips more easily than
thin, warm cream, as the viscosity is so great that the air incor-
porated cannot escape so easily. In ice-cream making, for the
same reason, a greater yield is obtained by using cold, thick cream.

Specific Heat of Milk.—The specific heat of milk is less than
that of water; that is, it requires less heat to warm a definite
amount of milk to a certain temperature than it does to heat the
same quantity of water to the same temperature. It also takes
less ice to cool the same volume of milk to a certain temperature
than it does to cool the same quantity of water to the same tem-
perature. The specific heat of milk is, according to Fjord, .94.
The specific heat of cream is about .7. It varies according to the
percentage of fat in the cream. The specific heat of butter is
about .4. From these figures it will be seen that it takes less
heat to warm milk, cream, and butter, and less cold to cool the
same substances, than it does to heai and cool water; but it takes
a longer time to heat or to cool milk, cream, and butter; that is,
the milk, cream, and butter are not as rapid conductors of heat
and cold as is water.

The maximum density of milk is not reached, like that of
water, at 4° C. but at about .3° C. The boiling-point of milk is a
trifle higher and the freezing-point a trifle lower than that of
water.

Effect of High Heating (180° and above) on Properties of
Milk.—The chiet effects of heat upon milk may be summarized
in the following headings:

EFFECT OF HIGH HEATING ON PROPERTIES OF MILK 39

(x) It destroys nearly all germs present in the milk.

(2) It diminishes the viscosity, or body.

(3) It drives off gases.

(4) It imparts a cooked taste (especially if not heated and
cooled properly.)

(5) It precipitates some of the albuminoids and ash constit-
uents.

(6) It destroys the properties of enzymes present in
milk.

(7) It divides or splits up the clusters and fat-globules.

(8) It caramelizes some of the sugar.

1. Destroys Nearly all Germs.—Heating milk to a tempera-
ture of about 180° F. for ten minutes destroys most of the germs
present. This is the temperature used in most creameries for
pasteurization. The details concerning the different effects of
temperature upon growth of germs properly comes under the
heading of bacteriology, and will be referred to more in detail in
the chapter on ‘‘ Ferments in Milk.”

2. Diminishes the Visc-sity, or Body.—Heating milk or
cream diminishes its viscosity; that is, it lessens the body or con-
sistency; and in cities where milk or cream is sold directly to
consumers, heated milk appears as if it had been adulterated.
This diminution in the body is claimed to be due to a breaking
up of the clusters, and the fat-globules and the caseous matter.
The chemical union of some of the calcium salts and the casein
is altered or destroyed.

The consistency of milk or cream can be restored by adding
a substance named viscogen. Russell and Babcock ! advise this
method of overcoming the apparent defect caused by heating.
It consists of making a strong solution of cane-sugar and mixing
it with freshly slaked lime. This mixture is allowed to stand,
and the clear solution coming to the top is the viscogen, which,
when drawn off and used in the proportion of one part of viscogen
to from 100 to 150 parts of cream, restores its body. This is
due to the fact that viscogen causes the fat-globules to cluster
together again, and the lime in the viscogen may combine with the

1 Bulletin No. 54, Wisconsin, 1896.

40 PROPERTIES OF MILK

nitrogenous constituents in such a way as to aid in the restora-
tion of the body of the cream or milk.

Nearly all dairy laws forbid the addition of any foreign sub-
stances to milk or cream. If viscogen is added, Babcock and
Russell suggest tha. it be named visco-milk, visco-cream, etc.
When the modification is made, no objection can be raised to its
legitimate use.

3. Drives off Gases.—When milk is heated, taints and gases of
different kinds pass off to some extent. This is facilitated by

Fic. 6.—Microscopic appearance of milk, showing natural grouping of the fat-
globules, Single group in circle, highly magnified. (From Bul. 64, Wis.)

heating and stirring in an open vessel. Many of these gases
also escape when milkis aerated and cooled in a pure atmos-
phere.

4. Imparts a Cooked Taste.—When milk is heated to 160° F.
or above, it assumes a distinctly cooked taste, which makes it
disagreeable as a food for many people. On this account, milk
for city supply in America is not generally heated above 145° F.
In practically all cities where milk is consumed directly, it is
subjected to low temperature pasteurization (145° F.) and held
at this temperature for twenty to thirty minutes. Under this
system the disadvantages of high pasteurization are overcome.

For butter-making purposes there are no objections to pas-
teurizing cream at a high temperature. The common practice

EFFECT OF HIGH HEATING ON PROPERTIES OF MILK 41

in most of our up-to-date creameries to-day is to pasteurize
the cream, under the vat or holding system, to 170° F. or above,
or, under the flash system, to at least 180° F.

The reason why this cooked flavor is found in milk when
heated is not well understood. It is supposed to be due to
the effect which heat has upon the nitrogeneous constituents
and the sugar.

5. Precipitates Albuminoid and Ash Constituents.—When
milk is heated, there is a tendency for the soluble salts and a
portion of the albuminoids to be thrown down, or changed into
an insoluble form.

The higher the milk is heated, the greater is this tendency.
If a sample of milk in a flask is subjected to intense heat, and
then allowed to stand, a fine white sediment will be deposited on
the bottom. This is believed to consist of minerals precipitated
from the milk.

When milk has been heated to about 170° F., and cooled,
rennet is unable to precipitate the curd in a normal way. The
curd resulting from adding rennet to pasteurized milk is flocculent
in nature. It does not assume that smooth and even texture
that curd from raw milk has when precipitated with rennet.
The behavior of pasteurized milk towards rennet can be ren-
dered normal by adding a small quantity of calcium chloride
(CaCl). Whether this would affect the quality of cheese mate-
rially has not yet been determined definitely. According to G.
Fascetti,| if pasteurized milk is used for cheese-making, the
cheese ripens more slowly than when made from raw milk. The
same investigator also claims that a larger quantity of cheese
is obtained per 100 parts of milk when pasteurized milk is
used. |

6. Destroys Properties of Enzymes.—As was mentioned in
_ the chapter on the composition of milk, there is a substance nor-
mal to milk named galactase. This is an enzyme. By heating
milk to about 175° F. the properties of the enzyme are destroyed.
Owing to this it is easy to determine whether a certain sample of
milk has been pasteurized or not. Galactase is present in milk in

' Exp. Sta. Record, Vol. 15, No. 10, 1904.

42 PROPERTIES OF MILK

so small a quantity that it cannot be determined quantitatively,
but only qualitatively.

A very sensitive and reliable test for determination of the
efficiency of pasteurization was invented by Storch a number
of years ago. This is fully described in Chapter XV on
“ Pasteurization.”

7. Divides the Clusters of Fat-globules.—The fat-globules in
normal milk are grouped in minute clusters. When milk is
heated, these clusters break up, and each globule exists more or
less independently. When heated to an excessively high tem-
perature, and exposed to this temperature very long, the fat-
globules tend to run together. This can be proved by heating
milk in an open vat for about half an hour. A small amount of
yellow fat will then be seen floating on the top.

8. Caramelizes the Sugar.—The brownish color which he
milk assumes when it is heated excessively is due to a change which
the milk-sugar undergoes. Fleischmann claims that the sugar
begins to change into a substance known as lacto-caramel at a
temperature of 160° F. This change, however, is not pro-
nounced enough to be apparent in the color, unless the milk
is heated a long time. ‘The higher the temperature is, and the
longer the milk is exposed to the heat, the more pronounced is
the change.

General Remarks.—While all of the above changes have
been found by investigators to take place when milk is heated,
they can, in a measure, be avoided, if special precautions are
taken in the heating and cooling with the special, recently
improved forms of apparatus for these purposes.

The present common practice of heating milk, for consump-
tion as such, to 145° F., and holding at this temperature for
twenty to thirty minutes, is accomplished without materially
changing its chemical or physical properties, or imparting to it a
flavor that is at all objectionable.

CHAPTER IV

MILK AND ITS PRODUCTS AS FOODS

HIGH VALUE OF MILK-FAT

THERE are two methods for the classification of foodstuffs for
animals and man, and both of these will be briefly considered in
this chapter, with special reference to milk and its constituents—
particularly milk-fat—as not only valuable but indispensable
parts of the dietary.

The older method may be spoken of as the chemical method.
It considers and classifies foods largely in accordance with their
content of water, protein, carbohydrates, fats and mineral matter.
This, in itself, is quite incomplete, as will be shown later.

The newer method, which is known as the biological method,
is based upon a study of the properties and values of the different
foodstuffs, through feeding them and noting their effect upon
growth, health and reproduction. Thismethod, though compara-
tively new, has made very rapid strides, and has established the
fact that food constituents which come under the same chemical
head are by no means either alike or of equal nutritive value.

There is neither the hope nor the expectation that the bio-
logical will supersede the chemical classification of foods and
foodstuffs, in the sense of dispensing with the aid of chemistry.
The true, unbiased student of the problems of nutrition recognizes
two things; first, that the chemical method has rendered and
will continue to render a very large service, and, second, that in
itself it is too mechanical and incomplete.

In the last analysis, the biological classification of foodstuffs
must prevail, but this does not mean that it and chemistry are
at variance with each other. Rather it means that there must
be a merging of the chemical into the larger or biological method,
and that in future a larger, fuller, more intelligent and less

43

44 MILK AND ITS PRODUCTS AS FOODS

mechanical use will be made of chemistry as an aid in deter-
mining the values of the different foodstuffs and how they may
best be combined with each other in the compounding of more
economical and complete rations and diets on which animals and
man will grow and thrive. At times the biological study of food-
stuffs may move in advance of chemistry, as it has already done
in discovering the presence in milk-fat of a fat-like or fat-soluble
substance, as yet unidentified, which renders this fat altogether
superior to other animal and vegetable fats lacking this growth
and health-promoting foodstuff. It is the province of chemistry
to ascertain, if possible, what this substance is. The same may
be said of a water-soluble substance which is not nearly so limited
as to its sources, being present in sufficient quantity in cereal
grains and most of the mixed diets.

CHEMICAL CLASSIFICATION OF MILK AND ITS PRODUCTS
AS FOODS

From the chemical standpoint, the constituents of the food
material consumed by animals and man are classified under the
heads of water, combustible matter and ash, mineral matter or
salts—all three terms being applied to the last class.

The combustible matter includes the carbohydrates (such as
starches and sugars), the fats (such as milk-fat, olive oil and
other plant oils, and meat-fat), and the proteins (such as the curd
of milk, the gluten of wheat and the muscle fiber of lean meat).

The carbohydrates and fats are largely burned to supply
heat and energy, and are also used for the making of fat in the
body and in milk.

The proteins are used, in part, for the same purposes as the
carbohydrates and fats, but their distinct function, which these
latter cannot perform, is that of supplying material for the
making of muscle and other body tissue, and the protein of milk.

The ash or mineral matter is used for making bone, regulating
the heart action and the elasticity of the muscles in general, and
preventing acidity of the blood and tissues.

Under the older classification of foods we find that milk

BIOLOGICAL CLASSIFICATION OF FOOD 45

and its products are given a very high place, on account of their
high content of the different foodstuffs or constituents, and their
high degree of digestibility. A quart of average milk is consid-
ered by such high authorities as Sherman of Columbia University
to be approximately equal in food value to a pound of steak,
or eight or nine eggs. He is here referring chiefly to their heat
and energy value and high degree of digestibility.

American cheese (a Cheddar cheese) may be regarded, in a
very large sense, as a concentrated form of milk, as it contains
most of the milk constituents, excepting the sugar. It has about
twice the food value of average meat. On this point Sherman
says “ Generally speaking, cheese sells at no higher price than
the ordinary cuts of meat. It is a fair general estimate that a
given amount of money spent for American cheese will buy about
twice as much food value as it would if spent for meat.”

Altogether apart from a distinctive and most important
function which will be considered later, butter has a very high
heat and energy value—a pound being equal to about five
quarts of average milk. It is by no means merely a relish, as it
has in the past been considered by many.

We cannot here afford the space to discuss the food values of
the various other milk products, such as cream, ice-cream and
condensed milk. It will suffice to say that cream occupies an
intermediate position between milk and butter, combining the
features of both.

BIOLOGICAL CLASSIFICATION OF FOODS
The High Value of Milk and Milk-fat under this Classification

The biological study of foods—based upon observations as to
the influence of various foodstuffs upon the growth and thrift of
animals—has revolutionized our ideas with regard to problems
of nutrition, and has established the fact that the biological
classification of foods is the true one. In doing so it has shown
that milk and milk-fat have values as foods which, a few years
ago, were quite unknown, and which as yet have not been deter-
mined chemically—or at least have been determined only in part.

46 MILK AND ITS PRODUCTS AS FOODS

It was but natural that biological students of the problems
of nutrition should give their attention to milk and endeavor to
ascertain wherein its different constituents excelled the corre-
sponding constituents of other foods. Knowing that the young
grow and thrive on a diet composed exclusively of milk, they
realized that this food must contain nutritive material of an
exceptionally high order.

Proteins

The proteins of plants differ from those of animals and of each
other. Animals do not take the proteins of their foods, whether
of plant or animal origin, and use them as such, without any
change. In the processes of digestion and assimilation, animals
break proteins up into the simpler substances, amino-acids, and
from these build up the proteins of the muscle and other tissues
of the body.

There are eighteen amino-acids that are considered in nutri-
tion problems. The protein of wheat (gluten) is able to supply
only a limited number of these in sufficient quantity, and some
not at all. The proteins of the corn kernel (zein, etc.) are
able to supply others, and so on with the proteins of the different
foods; but none of these is a complete protein food for the animal
body. ‘The chief protein of milk (casein) is, however, an excep-
tion, being a very complete and well-balanced protein, which is
able to supply the different amino-acids in sufficient quantities
and right proportions to build up muscle and other protein
’ tissue of the body. Thus we would say that milk furnishes pro-
tein of a quality quite superior to that of almost any other food.
This we see exemplified in the fact that the young animal lives,
grows and thrives on milk alone.

Ash or Mineral Matter

In the ash or mineral matter of the food there must be a
sufficiency of such elements as sodium, potassium, calcium,
magnesium, iron, etc., in the form of inorganic salts. These
perform very important functions. Each has its work to do,
and they are not interchangeable.

BIOLOGICAL CLASSIFICATION OF FOODS 47

In a mixed diet, there is usually, but not always, a sufficiency
of the compounds of the different elements mentioned. We
quote Sherman upon this point: “There must also be main-
tained in the body a proper balance between sodium and calcium
(the metal of lime). For example, the rhythmical contraction
and relaxation of heart muscle, which constitutes the normal
beating of the heart, is dependent upon this muscle being bathed
by a fluid containing the proper concentration and quantitative
proportions of sodium and calcium. Calcium is not always suf-
ficiently abundant even when the food is freely chosen; hence the
richness of a food in calcium is a factor affecting its value.”!
McCollum and Simmonds found as a result of their experiments,
“‘ that the deficiency in mineral elements in wheat and other seeds
is limited to three elements, calcium, sodium and chlorine.’’?

The ash of milk is present in liberal quantity, is of high qual-
ity and well balanced, and is rich in its lime content as a source
of calcium. ‘There is more lime in a pint of milk than in a pint of
limewater,

Two Unidentified but Essential Food Substances—One of These
in Milk-fat but not in Ordinary Fats

There are, in association with some of the foodstuffs, sub-
stances which have not as yet been identified chemically, pos-
sibly on account of the minute quantities in which they are
present; and yet observation, in feeding experiments, has shown
that they are indispensable. If these are absent from their
foods, animals will neither grow nor retain vigor.

As early as 1906, Hopkins of Cambridge (England) showed
conclusively that on an apparently complete food made up of
purified proteins, ordinary fats, carbohydrates and salts young
rats would not grow, but that when a very small amount of milk
‘was used—enough to make up about 4 per cent of the dry matter
of the food—growth became entirely satisfactory. This led him
to conclude that there were present in milk unidentified food
substances which he termed “ accessory ” articles of the diet.

1 Food Products, pp. 19 and 20.
* The Newer Knowledge of Nutrition, p. 23.

48 MILK AND ITS PRODUCTS AS FOODS

These would be what McCollum terms the “ fat-soluble A,”
which is found in milk-fat but not to any appreciable extent in
the ordinary fats, and the ‘ water-soluble B,” which is more
generally distributed in foods, particularly in diets of mixed
foods.

Bloch, a Danish physician, observed about forty cases of
severe eye trouble, accompanied by ulceration, in children near
Copenhagen. This would, without doubt, have ended in blind-
ness. These children had been receiving skim-milk, instead of
whole milk, in their diet, and were practically deprived of milk-
fat in their food. When the younger of them were given mother’s
milk, and the older either cow’s milk or cod liver oil, they
responded and recovered. He attributed the trouble to the lack
of fat in their foods; but it will be noted that in all cases the real
cause of recovery was the feeding of fats containing the, as yet,
unidentified fat-soluble which is present in the fats of milk, the
yolk of egg, the liver and other body glands, and the leaves of
plants, particularly such plants as alfalfa and the clovers.

Mori found fourteen hundred cases of similar eye trouble
amongst children in Japan; these responded to the feeding of
chicken livers.

It has been found both by McCollum and Davis, and by
Osborne and Mendel that milk-fat contains a fat-like or fat-
soluble substance whose presence or absence in a food, otherwise
entirely satisfactory, means the difference between growth and
no growth in the young. In addition to this, both these pairs of
investigators found that, deprived of such a fat as milk-fat, the
young animal would develop a disease of the eyes which would
ultimately cause blindness and, if persisted in, would end in
death; but that if this fat were restored in time the eyes would
become normal again and the young animal would return to its
former health and vigor and resume normal growth.

It would be unfair to credit any one man, or set of men
collaborating with each other, with the discoveries that have
been made during the past fifteen or twenty years—and par-
ticularly within more recent years—through the biological study
of foods. The list of investigators is rather a formidable one,

BIOLOGICAL CLASSIFICATION OF FOODS 49

and, as has already been indicated, includes students of the sub-
ject extending from America to Europe and even to far-away
Japan. Without doubt the best known of these in America is
Dr. E. V. McCollum, whose extensive and most valuable articles
appeared in Hoard’s Dairyman and other farm and scientific
journals, and who has issued a valuable book on the subject,
entitled, ‘‘ The Newer Knowledge of Nutrition.”’ In this book
he outlines the investigations conducted by him and his co-
workers—Babcock, Hart, Davis, Steinbeck, Humphrey, Parsons,
Funk, Kennedy, Simmonds and Pitz—and also familiarizes us
with the work of many other investigators.

As McCollum intimates, in order to secure reliable and exact
data it was necessary to feed purified foodstuffs (purified protein,
carbohydrates, fats and mineral salts), and in order to do this
and secure sufficient data within a reasonable time it was neces-
sary to experiment with small animals. For these reasons,
the experiments were conducted mostly with young rats, although
like results were also obtained with other animals, including
cattle and pigs. Accumulated data, from a variety of sources,
show that the resulis secured are equally applicable to the different
animals, including man.

In one of the earlier experiments with rats, conducted by
McCollum and Davis, they fed a diet composed of purified pro-
tein (casein) to the extent of 18 per cent, lactose or milk-sugar
20 per cent (supposed to be pure), about 5 per cent of some fat,
together with a salt mixture made up in imitation of the mineral
matter of milk, and the balance of starch to make up too per cent.
The results of this experiment were that when the fat used was
milk-fat growth could be secured, but that when this was
replaced by such fats as lard, olive oil or other vegetable oils,
there was no growth. When the fat of yolk of egg was used
instead of milk-fat it also induced growth. These experiments
established the fact that fats from different sources are by no
means equal in dietary value.

Following this a more elaborate experiment was planned and
carried out by McCollum and Davis. It will be noted that the
diet of purified foodstuffs, which proved a satisfactory one, was

50 MILK AND ITS PRODUCTS AS FOODS

made up of purified milk constituents. McCollum and Davis
next tried the wheat seed or kernel. They reasoned that it con-
tained protein, carbohydrates and mineral salts and fats or oil,
and that if these were mostly equal in quality to those of milk
the only foodstuff that might have to be added would be a growth-
promoting fat. They first fed wheat alone and then tried the
improvement of it with respect to one dietary factor at a time.
The following indicates the different combinations in which
wheat was fed, with results secured:

(a) Wihveat alone.) Gait ote geet ee eee te No growth, short life.
(2) Wheat, plus purified protein............ No growth, short life.
(3) Wheat plus a salt mixture which gave it a

mineral content, similar to that of milk Very little growth
(4) Wheat plus a growth-promoting fat (milk-

52215) Wea oe aN AP ad 8 AR eee moe i Wr“ No growth.
(5) Wheat, plus the protein, plus the salt mix-
ELIT Cs Me A, il Poole ee ml RN ec A ar tne Good growth for a time, few or no

young, short life.
(6) Wheat, plus protein, plus a growth-pro-

moting fat (milk-fat)................ No growth, short life.
(7) Wheat, plus the salt mixture, plus the
growth-promoting fat (milk-fat)...... Fair growth for a time, few or no

young, short life.
(8) Wheat, plus protein, plus the salt mixture,
plus a growth-promoting fat (milk-fat) Good growth, normal number of
young, good success in rearing
young; life approximately the
normal span.

This series of experiments again proves the necessity of a
growth-promoting fat. But it does more than this; it shows that
the proteins and mineral matter from different sources are not
of equal value, those of milk being altogether superior in this
respect to those of such a food as wheat. Other experiments
proved that the seeds of other cereals are, like wheat, quite
incomplete in themselves as diets.

In following up this investigation it was found that when
polished rice was substituted for wheat, in No. 8 of the series of
experiments just outlined, the diet failed utterly to induce
growth. This was puzzling. The investigators had been able
to induce successful growth through feeding a diet composed of

BIOLOGICAL CLASSIFICATION OF FOODS dl

purified protein (casein), milk-sugar (supposedly pure), salts in
imitation of the mineral matter of milk, and milk-fat. They
could see no reason why the polished rice, supplemented by puri-
fied protein, suitable salts and milk-fat should not be a complete
food. This was cleared up subsequently by establishing the
fact that the milk-sugar used in the former of these two experi-
ments, and the germ or chit of the cereal seeds, which had been
rubbed off the rice, contain a water-soluble substance essential for
growth, health and vigor.

The conclusions finally reached were, first, that amongst
the food substances (protein, carbohydrates and ash or mineral
matter) coming from different sources there is a marked differ-
ence in quality, and that those from milk are of a very high order;
and second, that there are two as yet unidentified substances
which are indispensable to growth and health, namely, the
unknown substance which is present in milk-fat, the fat of yolk of
egg and some of the glandular fats, which McCollum and Ken-
nedy subsequently designated “ fat-soluble A,” and a second
substance soluble in water, which they designated ‘ water-
soluble B.”” The absence of the former (fat-soluble A) not only
prevents growth, but also causes a serious eye trouble which, if
not corrected in time, will end in blindness and death. We have
already illustrated this point. The absence of the water-
soluble also prevents growth, and causes serious physiological
disturbances resulting in a form of paralysis, beri-beri, which is
quite prevalent where such foods as polished rice and bolted
flour form the main article of diet.

But this water-soluble is present in most ordinary food
substances, and particularly in a mixed diet, whereas the sources
of the fat-soluble are quite limited, the fat of milk, in the form
of milk and butter, being the chief of these.

_ In support of what has been said, the utterances of some of
our leading physiologists and students of nutrition may be
quoted.

Dr. H. C. Sherman, Professor of Food Chemistry, Columbia
University: ‘‘ Especially in the feeding of children should milk
be used freely, because of its many advantages as a tissue-

52 MILK AND ITS PRODUCTS AS FOODS

building and growth-promoting food. A quart of milk a day
for every child is a good rule easy to remember.”’

United States Food Administration: “ Milk is one of the most
important food sources the human race possesses. For the
proper nourishment of the child it is absolutely indispensable
and its use should be kept up in the diet as long as possible. Not
only does it contain all the essential food elements in the most
available form for ready digestion, but the recent scientific dis-
coveries show it to be especially rich in certain peculiar properties
that alone render growth possible. This essential quality makes
it also of special value in the sick room. Jn hospitals it has also
been shown that the wounded recover more rapidly when they
have milk.

“For the purpose of stimulating growth, and especially in
children, butter-fat and other constituents of milk have no
substitutes.”

Dr. E. V. McCollum, Johns Hopkins University: ‘I have
come to the conclusion, after carefully analyzing the probable
effectiveness of the combinations of foods employed in human
nutrition, that the efficiency of a people can be predicted with
a fair degree of accuracy from a knowledge of the degree to which
they consume dairy products. Probably the use of meat and of
milk and its products will, in nearly all cases, run more or less
nearly parallel, and I venture to assert that it is the milk and
butter and cheese, and not the meat which has the good influence
in the promotion of the virile qualities of the people.

“Milk is worth much more than its energy value or than its
protein content would indicate. It is the great factor of safety
in making up the deficiencies of the grains which form and must
continue to form the principal source of energy in our diet.

“Tt seems probable that the only unidentified substance
which is physiologically indispensable, which is not sufficiently
abundant in the diets employed by the people of the United
States and Europe where there are used insufficient amounts of
milk, butter, cream, eggs and the leafy vegetables, is the fat-
soluble A.”’

“IT wish to again emphasize the fact that there is no way to

BIOLOGICAL CLASSIFICATION OF FOODS 53

supply this dietary factor (fat-soluble A) in the food of children
except in the form of milk-fat, and milk is therefore an indis-
pensable food for the young.”

Attention should be called to one other point. It has been ~
suggested by some that possibly pasteurization of milk or cream
destroys the growth-promoting qualities of the “ fat-soluble A ”
in the fat. Osbourne and Mendel found that passing live steam
through milk-fat for two hours did not affect it, and McCollum
and Davis found that it was not affected by being heated to
the boiling-point of water. This should be satisfactory evidence
that pasteurization of milk or cream in no way affects the growth-
promoting qualities of the milk-fat.

CEIAR TERA:
FERMENTS IN MILK

Definition. — The changes which milk undergoes when
allowed to stand at a suitable temperature are commonly called
fermentations, and the agencies which bring about these changes
are called ferments. At one time the ferments were classified
under two heads, viz., organized ferments (bacteria, yeasts
and molds), and enzymes or unorganized ferments, such as those
found in rennet and other fluids in the digestive tracts of animals.
This distinction is no longer made, since bacteriologists and
physiological chemists have reached the conclusion that the
fermentative changes, due to the action of germ life, are caused
by enzymes which these micro-organisms produce. However,
the enzymes themselves may, from a dairy standpoint, be classi-
fied as follows:

(1) The pre-existing enzymes of milk, or those which are
formed during milk secretion and consequently are in the milk
when it is drawn from the cow. ‘The first of these was dis-
covered by Babcock and Russell of the Wisconsin Station, in
1889, and was named galactase by the discoverers. It is a
tryptic ferment. Since then others, such as catalase and peroxi-
dase, have been discovered. It would seem, from investigations
made by Russell and Babcock, that the inherent enzymes of
milk, which are digesting ferments, are essential to and play an
important role in the ripening of the Cheddar type of cheese.
They find that it is impossible to produce a typical, normal
Cheddar cheese from thoroughly pasteurized milk. According
to Storch, the peroxidase has the power of decomposing hydrogen
peroxide and setting free “ active” oxygen. As this ferment is
not destroyed until milk or cream is heated to a high temperature,

54

FAVORABLE CONDITIONS FOR BACTERIAL GROWTH <5

it forms the basis for the Storch test for the efficiency of the pas-
teurization of milk or cream for butter-making. This test is
described in the chapter on Pasteurization.

(2) Enzymes developed through the action of germ life—
bacteria, yeasts and molds. These are many and varied, and
cause most of the changes that take place in milk and its products,
such, for example, as the ordinary souring of milk or cream, and
the development of flavor and aroma in cream ripening.

(3) Enzymes found in the digestive fluids of animals. All are
familiar with the fact that rennet is used in cheese-making. It
contains a ferment known as rennin.

It is the second class of ferments or enzymes, the class due to
the action of germ life (principally bacteria), which is of the great-
est importance in connection with dairying, and with the control
of which the dairyman concerns himself most. These ferments
are capable of working profound changes, some desirable and some
very undesirable.

Size and Shape of Bacteria.—In size, bacteria are the smallest
organisms that exist, so far as known. The size varies consider-
ably. Russell! gives the average diameter as soo00 of an inch.
They are so inconceivably small and light that nine hundred
billions of them would only weigh 25 of an ounce.’

Bacteria also vary considerably in shape. They are as a
rule classed into three groups: (1) The bacillus or rod-shaped;
(2) The coccus or ball-shaped; (3) The spirillum or spiral-shaped
(like a corkscrew). Some types of bacteria are classified accord-
ing to the way in which they adhere to each other. For instance,
when two cocci occur together and form a pair, they are called
diplococci; when cocci occur in chains, they are called strepto-
cocci; when cocci appear in bunches, they are called staphylo-
cocci, etc.

FAVORABLE CONDITIONS FOR BACTERIAL GROWTH

Food.—Bacteria, like other plants, need food for their exist-
ence. The food passes into the bacterial cell in solution, but
many organisms use materials not in solution by producing

1 Dairy Bacteriology. 2 Milk, Its Nature and Composition, by Aikman.

56 FERMENTS IN MILK

enzymes that dissolve them. Nitrogen, carbon, oxygen, hydro-
gen and mineral matter are essentials for bacteria. These sub-
stances are furnished in abundance in milk from casein, albumen,
milk-sugar, and the mineral salts. Butter-fat in milk is said to be
of little value as a food for bacteria.

Some organisms, including yeasts and molds, tolerate con-
siderable amounts of acid, while others do not. Most bacteria,
however, prefer a neutral or slightly alkaline substance. Dark-
ness is essential to some bacteria, and is preferred by the majority
of the different species. Bright sunlight is a very effective

Sy Sim Wp
SVQ. a, WT
SIN Un OD a Ay WAN g
SPP COD aX YU° Nye gh Geada®
7 Of RANT TN:
Se AD TE Vo Ce
aw ' ZN yal
eae MPSS fl oop OY od Ix
SMW Noa engs ge F ine Ni
( et 7 Ge Ay Nae Oy) Iy
ap MS UNS, Ti V 1 Deane
AVN Sy " ! an ‘\
Vw iy \ ! 7} 4 NU
7 SAO 7 EROS! ai, LINEN
5] ra VS SOS: Ss Catia
ENG | Wp KOM Zo. 19 8 CS
‘ ‘
/ NW Ps Ucn SR MANTRA ON
a \ ERE ea Wand iy 20S Se
i] Bags DO Hl SS Ne pf ANS
b SS AN ETN SIS ig Mang) SS
a aN 1,1 i vs 0 ', \ NN /
FEZ IO) eG i Nay A pa VaNise OS AA
- Vy 4 ‘ i j
(PA 2 pW USSU Te WARE gay Oy Fhe tty 104
VA SUPT SAD Son Haein By 1 !
\ SS Dae By h\\
AX re VI VSS ~ \ a as Neer
1s Nt it pp 1 alan OM
UNS DY) ST Uy Nae Dey)
a hy 2 Yio WN A Oia
ZN Ji \l NOC NING Ways
Zo Westy i Ve Sah ty Vu SZ
TD Sa Wah ike Oe ae ky w\),
SLM Sop SUS So pat
ER NSUS AR LC yh VY UN Ay OO
Ss MOIS pS Sat UGB
A) \ TOS 5
APTN SS td

Fic. 7.—a, single bacterium; 6, progeny resulting from the growth of a bacterium
during 24 hours in milk at 50° F.; c, progeny of a bacterium during 24 hours
growth in milk at 70° F. At 50° F. multiplication was 5-fold. At 70° F.
the multiplication was 750-fold. (Bul. 26, Storrs, Conn.)

germicide; it is fatal to all species, so far as known. Some germs
require air for their growth. ‘These are called aerobic. Others
again grow only in the absence of air. These are called anaerobic.
Some grow under either or both conditions, and are called
facultative.

Temperature.—Favorable temperature is essential to bac-
terial growth. Temperature is, indeed, the most important
means by which the growth and development of bacteria can be
controlled. The range of temperature at which bacterial
growth is likely to occur may be placed between freezing-point and
a little above 110° F. There are, however, exceptions to this

FAVORABLE CONDITIONS FOR BACTERIAL GROWTH o7

range. Some few species will grow at as high a temperature as
140° F., and B. bulgaricus will grow very rapidly at 110° F.

The growth of bacteria at these extreme temperatures is
usually very slight. Even at 50° F. the rate of growth is very
slow. According to experiments conducted by Dr. Conn, the
multiplication of bacteria at 50° F. was 5-fold, while at 70° F.
the multiplication was 750-fold. The following table shows the
number of bacteria per cubic centimeter in milk kept at different
temperatures.!

es Tike Ttts In 50 Hrs.| No. of No. of
No. at u ie u be as or at Time | Hours be- | Hours be-
Outset R e 2 - 5 of Curd- | fore Curd- | fore Curd-
at 70 at 50 ‘ @ Ino o| 7: °
ling at 70° jling at 50° ling at 70

46,000 39,000 240,500 |I,500,000 | 542,000,000 190 56

47,000 44,800 360,000 127,500 | 792,000,000 280 36
36 hours

50,000 35,000 800,000 160,000 | 2,560,000,000 172 42
42 hours

All bacteria do not have the same optimum growing tem-
perature. Some species develop most rapidly at one tempera-
ture, while other species prefer a different temperature for the
greatest development. It is on this account that certain tem-
peratures are employed in ripening starters and cream. Accord-
ing to researches by Conn, Bacterium aerogenes develops very
rapidly in milk at 95° F. This particular species, producing
much gas and an unpleasant flavor, sours milk very rapidly. As
a rule, milk which has been held at this high temperature con-
tains a preponderance of this undesirable species of bacteria.
_At77° F. results are more uncertain; the species of bacteria
which will predominate in milk at this temperature depends in
large measure upon the number of each kind originally present.
According to Conn Streptococcus lacticus has the highest relative
growth at about 70° F. This particular species produces no gas,
and its presence is desirable in cream for butter-making. Milk

1 Bull, 26 Storr’s Sta., Conn.

58 FERMENTS IN MILK

kept at this temperature will, in most cases, providing it has pre-
viously been properly treated, develop a pleasant acid taste, will
curdle into a smooth uniform coagulum, and will contain a pre-
ponderance of the species of germ mentioned above.

At as low a temperature as 50° F. acid-producing types of
bacteria do not develop very well. But Conn maintains that
miscellaneous species of bacteria that produce unfavorable
results develop at this temperature. While milk does not easily
sour at this temperature, it should be remembered that undesir-
able germs are constantly developing.

As it is practically impossible to exclude all of the bacteria
from milk during milking and the handling of the milk, it is
very essential that the multiplication of the germs present be
checked, or at least retarded; and this can be done by controlling
the temperature of the milk. As low temperature is effective in
checking the multiplication of the bacteria, the sooner the milk
can be cooled after it is drawn, the better it will be likely to keep.

Moisture.—Moisture is one of the essentials for bacterial
growth. As milk is composed largely of water, bacteria find in
milk a good medium for growth. All the other required food
elements are also found in abundance in milk. Damp utensils
and rooms are always more conducive to the growth of germs
than are utensils and rooms which are thoroughly dried and
ventilated. This is well illustrated by a refrigerator. A very
damp dark refrigerator is always more conducive to the growth
of molds in butter than is a dry refrigerator.

Unfavorable Conditions for Bacterial Growth.—The reverse
of the favorable conditions mentioned above would be unfavorable
to the growth of bacteria. As it is practically impossible to make
conditions unfavorable for the growth of bacteria by taking
away food, other means must be used. Extremely high tem-
peratures destroy bacteria. Low temperatures check their
growth, but so far as known do not destroy them. Absence of
moisture and presence of direct sunlight are conditions which are
not conducive to bacterial growth. Certain chemical substances
when added to milk, or to the medium in which the bacteria are
present, are very unfavorable to their growth. Some of these

UNFAVORABLE CONDITIONS FOR BACTERIAL GROWTH 59

chemicals entirely destroy all germ life even when added in very
small quantities. These are called disinfectants (formaldehyde,
corrosive sublimate, etc.). Other chemicals are more mild in
their effect upon germ growth, and merely inhibit or retard the
growth of micro-organisms. The chemicals which have this
milder effect upon germs are called antiseptics. Boracic and
salicylic acids are examples. Practically all disinfectants are

Itc. 8.—Shows a plate exposed in pasture where air must have been very pure
and free from germs, (Bul. 87, Nebraska.)

violent poisons, and should not be used in any quantity or in
any form in milk or dairy products which are intended for human
food. The milder preservatives or the antiseptics, are, as a rule,
not sO poisonous or injurious to human health. In some coun-
tries they are allowed to a small extent. For instance, according
to reports, the laws of England permit the use of boracic acid
in butter to the extent of 0.5 of r percent. It is, however, safest
not to use any of these chemicals, except for preserving samples

60 FERMENTS IN MILK

for analytical or similar purposes. As low and high tempera-
tures are so effective in producing unfavorable conditions, these
should be chiefly employed in controlling the growth of micro-
organisms in the dairy industry. |

Kind of Germs Found in Milk.—The number of species of
germs found in milk has not yet been definitely established, due
chiefly to the fact that it is in some instances difficult for bacteri-
ologists to differentiate one species from another. The descrip-

Fic. 9.—Shows a plate exposed one-half minute under a cow’s udder treated with a
5 per cent solution of carbolic acid. (Bul. 87, Nebraska.)

tion of one species of bacteria by two different bacteriologists
may vary considerably, as the characteristics of the germs
depend so much upon the conditions prevailing throughout the
classification process. Over 200 different species have been
described. It is possible, however, though all of these types
may have different morphological and physiological character-
istics as described by different bacteriologists, that some two or
more of the 200 types may belong to one species.

KIND OF GERMS FOUND IN MILK Gl

For this purpose, it is sufficient to classify the bacteria into
three groups, viz., (1) those which are harmful to the butter-
making industry, (2) those which are beneficial, and (3) those
which are indifferent, or produce neither good nor bad results.

From the farmer’s or milk-producer’s standpoint, none of
these bacteria are desirable. Each milk-producer should make
it a point to prevent their entrance and suppress their develop-

Fic. to.—Shows plate exposed one-half minute under cow’s udder treated by merely
brushing with the hand; each little spot represents a colony of some kind of
bacteria. (Bul. 87, Nebraska.)

ment in milk and cream to as great an extent as possible. The
creamery operator should endeavor to suppress all of the harmful
germs, and foster the development of the desirable ones.
~The germs which are desirable belong to the acid-producing ©
types, such as Streptococcus lacticus, and the associated flavor
and aroma-producing types, such as Streptococcus citrovorus.
The harmful bacteria include those which produce bitter
milk. red milk, blue milk, yellow milk, slimy milk, gas, and

62 FERMENTS IN MILK

undesirable flavors and aromas. There are a number of species
belonging to this group. The pathogenic germs, or disease-
producing bacteria, must also be classed with the harmful bac-
teria. It is not the intention in this work to give an extended
discussion of this subject. For such discussion see special works
on Dairy Bacteriology.

Number of Bacteria in Milk—The number of bacteria found
in milk varies so much that it is practically impossible to state
accurately the average number. The number of germs found
varies according to several conditions, such as degree of cleanli-
ness of cows, utensils, and milker; degree of purity of the atmos-
phere when the cows are milked; the temperature at which the ©
milk is kept and the time it is held. When the milk is being
produced under the best practical sanitary conditions, the number
of germs need not exceed 10,000 per cubic centimeter. Such
results cannot be obtained unless extreme precautions are taken.
Milk produced under average farm conditions seldom contains
less than 50,000 germs per cubic centimeter shortly after the
milking. Milk which is produced under filthy conditions, and
which is several hours old, may contain several millions of bac-
teria per cubic centimeter.

Sources of Bacteria in Milk.—Bacteria are widely distributed
in nature. They float in the atmosphere and adhere to particles
of dust. Especially is this so in the dusty cow-stable. They
are present in all well water. to a greater or less extent, and are
very abundant in streams and rivers. They are present in the
soil to a depth of several feet, the number decreasing with the
depth. As these germs are practically present everywhere, the
sources of germs in milk may be said to be all around us. The
principal sources of germs in milk are, however, unclean dairy
utensils, unclean cows, and unclean surroundings. As these
germs multiply chiefly by fission, or by one cell dividing into two,
it is plain that the number of germs will increase very rapidly
under favorable conditions. Under the most favorable condi-
tions it requires approximately twenty minutes for this process of
fission to take place.

Some germs develop small bodies within the cell, called

SOURCES OF BACTERIA IN MILK 63

spores. It is not difficult to destroy the sporeless cell by heat,
but the spores are very resistant to unfavorable conditions.
The spore-bearing bacteria are difficult to kill; boiling for a short
time will not destroy them. Hammer is satisfied that they are
destroyed by prolonged boiling. Another method is to heat the
milk to destroy all the organisms in the vegetative stage, then
cool it to a temperature favorable to growth and allow the spores
to develop into the vegetative stage, and again apply heat. In
this way milk can be rendered entirely sterile. A single heating

A B

Fic. 11.—The wrong and the right kind of a milk-pail. A, the ordinary type of
pail showing sharp angle between sides and bottom; 8B, the same properly
flushed with solder so as to facilitate thorough cleaning. The lower figure
represents a joint as ordinarily made in tinware. The depression a affords
a place of refuge for bacteria from which they are not readily dislodged. This
open joint should be filled completely with solder. (From Bul. 62, Wis.)

under pressure (fifteen minutes at 15 pounds pressure) kills them
at once.

It has been demonstrated by several investigators that freshly
drawn milk is not a good medium for bacteria to develop in.
In fact, several experiments seem to indicate that milk acts as a
germicide to certain varieties of bacteria. For instance, the
cholera germ is to some extent destroyed in fresh milk, but it is not
known to what extent. Organisms producing lactic acid check
the multiplications of these pathogenic bacteria. This germicidal
property is said to be more or less common to all the animal
secretions.

64 FERMENTS IN MILK

Effect of Thunder-storms on Souring of Milk.—It is a common
impression that thunder-storms hasten the souring of milk. This
was attributed to the electricity in the air accompanying the
storm. Experiments by several investigators have proved
that electricity does not have any effect on hastening the fer-
mentative changes of milk. The reason why milk sours more
quickly when an electrical storm is approaching is that the air
temperature is usually higher then than at any other time. This
higher temperature warms the milk and creates more favorable
conditions for the rapid multiplication of the germs present in the
milk. It is for this reason that milk sours more quickly during or
previous to a thunder storm than at any other time.

CEPA Ke vil
ABNORMAL MILK

Colostrum Milk.—Colostrum is the milk yielded immediately
after calving. As the time of calving approaches, a cow usually
diminishes in her milk-producing capacity. Most cows become _
dry about two months previous to parturition. If they do not
naturally stop giving milk, they should be dried up so as to have
a seven weeks’ rest before calving. When the rest has been
given, the cows yield, immediately after calving, milk which has
a composition and characteristics different from those of normal
milk. If the cow continues to give a copious flow of milk up to
the time of calving and is not allowed any rest, the difference in
the milk yielded before calving and after calving is comparatively
slight.

The composition of colostrum varies considerably during the
first three days after calving. According to Engling, as reported
by Richmond, the composition is as follows:

Per Cent
VIL Ue Teena recta Cr RO at tense 71.69
1 RY i cork ne Nie genase It I le ER eae Bh! 2 Ba
Paiamen cide | WaAselin eee a ment ee 4.83
JANA OUD ASTON re a ean cok 15.85
SIUUSE teni epee eae ONE SAO 2.48
VANS Ole Wiarton Sa cote ane 8 1.78

Colostrum greatly changes in composition and appearance as it
gradually assumes the characteristics of normal milk. It is at
first reddish yellow in color, and has a viscous and slimy con-
sistency. It is a food which the newly born calf should not be
deprived of, as it seems to be specially suited for the digestive
tract of the young calf.

65

66 ABNORMAL MILK

It will be seen from the above table that the water content
of colostrum is less than that of normal milk. The fat content
is also a little lower. ‘The most striking characteristics of colos-
trum, however, are the low content of sugar, and the large amount
of albumen. Of the latter substance very little is present in
normal milk. The mineral constituents of colostrum also run
quite high. Its specific gravity varies from 1.046 to 1.079.
When it is boiled, the nitrogenous matter coagulates. The
colostrum is not considered suitable for food until about four
days after parturition. Whenever it can be boiled without coag-
ulating, it is claimed to be safe to use. At times a cow’s udder
becomes inflamed after calving. In such cases the abnormal
qualities of the cow’s milk will extend over a greater period of
time than that mentioned above.

Salty Milk.—The average chemical analysis of salty milk as
calculated from results obtained by the analysis of such milk
from four cows, given by Béggild,! is as follows:

LEN cl giant ae Denon \ ttre, mate aa QI .09
AE eliteett sa Pi Ve eae gt cient as eva 2EOO
Nitiogenousematter se a eer 2.90
SUBATANS Yai enee tes ee ee 32.01
Dac) | WAH Mea Soe tity de OARS ey BS 85

It has an average specific gravity of 1.0244.

Salty milk does not occur very often, but whenever it does
occur, it is difficult, and, so far as known, impossible to cure
without drying up the cow. Two samples of such milk have
recently come within the authors’ notice. It had the appearance
of normal milk, a foul smell, and a very salty taste. The two
samples contained 1.7 per cent and 1.9 per cent of fat respectively.
They soured and curdled in a normal way at living-room tem-
perature in about thirty hours. At this stage they were very
foul in smell, and unpleasant in taste.

The cows which had produced this milk had both calved
about three months previously. It occurred in the month of
July, when pastures were quite good. The udders of the cows

1 Maelkeribruget in Denmark.

BLOODY OR RED MILK 67

were in an apparently normal condition. At first it was thought
that some conditions in the pasture caused this abnormal milk.
The cows were taken into the barn, and fed on dry food for
two weeks, but without any change in the quality of the milk.
Gradually they dried up.

The secretion of this salty milk was believed to be due to the
long time during which the cows had been yielding milk without
any rest. They had been given no rest previous to the last
calving. It is also believed that this quality of milk will occur
more frequently when the cows are near the close of the lactation
period.

While the above two causes are perhaps the most common,
they are not the only ones. Salty milk has been obtained in
cases where these reasons could not be ascribed. Béggild has
found that salty milk has been secreted by cows with abnormal
udders. He has also demonstrated that it was the diseased part
of the udder from which the salty milk was yielded. ‘The healthy
portion of the udder yielded normal milk. It is possible that
an obscure, diseased condition of the udder may be the entire
cause.

Salty milk is of course undesirable in the dairy or creamery.
It is very disagreeable to the taste, and in a fermented stage
becomes very foul.

Bloody or Red Milk.—Bloody, or red milk is caused, first,
by an abnormal condition of the cow’s udder, which may or may
not be apparent; and second, a red color may be developed in
milk after standing, through the action of bacteria.

The bloody milk, caused by an inflamed udder, often assumes
a reddish-yellow appearance, and may, if not examined care-
fully, be mistaken for colostrum. Bloody milk produced by an
inflamed udder may be distinguished by small blood particles,
which will settle to the bottom, and can be noticed if the sample
is placed in a glass test-tube. In bloody milk caused by bacterial
growth the blood does not show at the bottom, but instead,
previous to stirring the milk or cream, it appears on the surface
in small red dots. The red color which:commonly occurs in milk ©
is due chiefly to a species of germ called Micrococcus prodigiosus.

68 ABNORMAL MILK

Colostrum will show reddish cream on the surface, but no blood-
like material will separate out.

Blue Milk.—Blue milk is quite commonly found. Formerly
it was thought that this color was due to the condition of the
casein in the milk, but since more has been discovered in regard
to the effect of germ life upon conditions and properties of milk,
it has been proved that blue milk is caused by bacteria ! (Bacillus
cyanogenus). This particular germ produces the blue color in
the milk only when the milk has an acid reaction. When sterile
milk is inoculated with this particular germ, the blue color is not
produced, but by the addition of a little acid, or by inoculating
the milk with the bacteria that produce lactic acid, the blue color
is produced. ‘This seems to be one of the instances of symbiotic
action of bacteria in milk. There are probably other causes,
but they are not known. This germ, according to Aikman, is
killed by heating the milk to about 176° F. The germ ceases to
work as soon as milk is coagulated.

Yellow Milk.—According to Aikman,! yellow milk is caused
chiefly by one species of bacteria, named Bacillus synxanthus.
This micro-organism belongs to the group of ferments that act
upon the fat of milk. There are different shades of yellow pro-
duced in milk, caused by different species of bacteria, but the
above-mentioned one is considered to be the principal cause.
Some produce a brilliant yellow color, while other species first
curdle the casein, and then digest or dissolve it into a yellow or
amber-colored liquid.

Ropy Milk. —Slmy or ropy milk is not common, but is
sometimes encountered by milk-dealers and is caused by certain
micro-organisms. Aikman mentions the fact that no less than
eighteen different and distinct organisms have been identified as
associated with this shmy fermentation. Most of the investi-
gators agree that two organisms are chiefly responsible for the
slimy condition. One of these is Bacillus lactis viscosus,? which
grows best in the presence of air and neither forms acid nor thrives
in an acid medium. This germ has been found to be frequently

1C. M. Aikman, in “ Milk, Its Nature and Composition.”
2 Adametz, Landw. Jhr., 1891, p. 185.

BITTER MILK 69

present in surface waters. Bouska broke off a sliver from a
water tank which, when put into milk, inoculated it with an
organism that produced ropiness. The very fact that milk
dealers in cities are occasionally troubled with this sliminess in
milk indicates that precautions are essential in order to avoid the
presence of this ferment. The germ, when it once gains
entrance to a milk establishment, is very difficult to eradicate. |
In order to overcome the trouble it may be necessary to cover
the whole inside of the milk-store, and all of the vessels used
for handling the milk, with sour coagulated milk. The lactic
acid germs present in this milk gain ascendency over the germs
causing sliminess and in that way the trouble may be eradicated.

Streptococcus hollandicus' is another species which produces
sliminess in milk. It differs from the ferment mentioned above
in that it grows in the absence of air and produces acid. It is
used in Holland, in the preparation of the slimy whey (lange
Wei) starter which is added to milk used in the manufacture
of Edam cheese, just as we use a pure culture lactic acid
starter in connection with Cheddar cheese-making.

Sometimes milk is slimy when drawn from the cow—most
frequently when there is inflammation of the udder. There
are, in such cases, no bacteria present in the milk as the cause
of the ropy or slimy condition. We quote Russell and Hast-
ings: “ The direct cause of the abnormal condition in milk is
the presence of fibrin and white corpuscles from the blood, which
form masses of slimy material; in such cases the trouble does
not increase in intensity with age, nor can it be propagated by
transference to another sample of fresh milk.”

‘Bitter Milk.—This is one of the most common kinds of abnor-
mal milk, and like some of the others, may have more than one
cause. It may be due to some undesirable food that the cow has
eaten, or to the development of certain germs in the milk. If
caused by the food eaten by the cow, the bitter taste is recog-
nizable immediately after the milk has been drawn. Ifit develops
on letting the milk stand, it is caused by bacterial growth.

Several germs have been found to be associated with the pro-

1 Milch Zeit., 1889, p. 982.

70 ABNORMAL MILK

Oe
VR
SEDC

Fic. 12.—Showing effect of gassy fermentation in milk. The floating curd in 2 and 3 shows the presence of
gas-producing ferments.

MILK FROM COWS WHICH HAVE BEEN IN MILK tal

duction of this bitter flavor in milk. Conn has described a
micrococcus which produces a bitter flavor, and Weigmann has
described a bacillus which produces a similar effect. Nearly
all of the investigators agree that the germs causing the bitter
flavors in milk belong to the group which acts upon the casein.
The bitter flavor is most commonly found in milk that has been
heated and then cooled to a low temperature. The heat destroys
the bacteria that produce lactic acid, but does not kill those that
produce the bitter flavor, owing to the fact that they are spore-
producing.

The germs that produce a bitter flavor do not develop in
milk that is partly soured, because an acid reaction is unfavorable
to their growth. .

It was formerly thought that the organisms that cause the
bitter flavor in milk produced butyric acid. This theory,
however, has been largely overthrown, as it has been found that
these germs are chiefly of the kind which peptonize the casein
and produce gas.

Milk from Cows which Have Been in Milk for a Long Period.—
The difference in the composition of the fat yielded by cows in
different stages of the lactation period does not seem to affect
the quality of the milk to a noticeable extent. If the cows have
been giving milk an unusually long time, the milk may become
abnormal.

The impurities in the small amount of milk yielded by a cow
almost dried up are quite apparent, and the causes of the presence
of these impurities are readily understood. The small amount of
milk drawn from such a cow would contain a proportionately
larger amount of dirt and germs than would a larger amount of
milk drawn from a cow yielding more milk, providing the cleanli-
ness of the udder and manner of milking were the same. Cows
giving a good quantity of milk always seem to have a cleaner
udder. This has been laid to the more vigorous circulation of the
blood in the udder of the cow that yields a larger portion of
milk.

When cows calve once a year, and have a rest of about seven
weeks previous to parturition, if proper precautions are taken

72 ABNORMAL MILK

concerning cleanliness, they seldom yield milk from which a
first-class quality of butter cannot be produced. In practice
calving does not always occur at regular intervals. Several!
instances have come within the authors’ notice where cows have
been in milk for two years or more without coming in fresh.
Such a condition happens quite frequently on small farms, where
the cows kept are so few that it is deemed impracticable to keep a
bull. As a consequence cows are not served at the proper time,
and great irregularities in calving are introduced.

At times it also happens that cows become barren. In such
a case they are usually milked as long as they will produce even a
very small quantity of milk. Milk produced under such con-
ditions is likely to become abnormal in character. It may
remain normal with a slight increase in the fat-content. The
abnormal milk, so often complained of, is usually the result
of similar circumstances. It is a common belief that milk
yielded by such animals always contains a high fat-content, but
it may contain very little fat, and may be salty. It may also
appear normal, and the cream when separated appear viscous
and dead. Bdoggild states that at the creamery the milk from
one barren cow has more than once produced difficult churning.

Milk from Spayed Cows.—H. Lennat has given this kind of
milk considerable study. He finds that milk from spayed cows
may vary in quality to the same extent as milk from normal cows.
The solids of milk, as a rule, increase as the spayed cow advances
in the milk-giving period. This is especially noticeable in the
fat, sugar, and casein. Such milk is considered to be of extra
good quality, and is recommended as being especially suitable
for infant-feeding.

Milk from Sick Cows.—Too much cannot be said against the
use of milk from sick cows. As soon as the cows decline in health,
the quantity is noticeably decreased, and the quality is usually
abnormal. The kind of milk yielded varies with different cows
and different diseases, but it is interesting to note from the
study of this subject, by several men, that the milk-secreting
glands are quickly affected by disease and are unable to perform
their proper functions. Even a slight derangement of the

MILK FROM SICK COWS 73

digestive organs may have a marked influence upon the flavor
of the milk and butter. When cows do not clean well after
calving, the milk secreted by them always has an undesirable
taste. During the time of sexual excitement of the cow, milk is
usually decreased in quantity, and in a great many instances
possesses a very disagreeable flavor. :

When a cow’s udder is inflamed, the milk usually assumes
an abnormal condition. It usually contains large, white slimy
lumps. According to Bang,! this condition is caused by a small
round bacterium, and is contagious. When this germ is inocu-
lated into the udder, the cow becomes feverish and the milk slimy.

When cows become infected with tuberculosis to such an
extent that the udder shows lesions and nodules, the composi-
tion and appearance of the milk is altered considerably. Milk
from such cows contains tubercle germs, appears yellowish-
brown in color, and has an alkaline reaction. The composition
of such milk has been studied in Denmark and reported by
Béggild to be as follows:

NViciiei a reese euen ot) Gynt an. Wa Un: 88.57
TEEN Deedee a ratg ete aie Bae peace aio ARIE EA Bo 55
A\loibLaMTTAVONC NS, SH ose Hee bee ee 5.69
SURES RINSE eae eae Neh aintog ex ar ho Os
ENG) Oia sl each as Sentai Nee a ein ola aba tas 94

These results represent the average of four samples taken from

the diseased part of the udder. It will be seen that the greatest

variation from normal milk consists in the small amount of sugar

it contains and the high per cent of ash and nitrogenous matter.
1 Maelkeribruget i Denmark, by Béggild.

CHAPTER Vil
VARIATION OF FAT IN MILK AND CREAM

As the variations in the per cent of fat in milk and cream are
due to such widely different causes, it has been found expedient
to divide this chapter into two parts.

JeveecID JL
VARIATION OF FAT IN MILK

The percentage of fat in normal milk varies a great deal
more than that of any of the other constituents. Dr. Richmond
reports that the fat of milk may go as low as 1.04 per cent and
as high as 12.52 per cent. Such extreme variations are, of course,
abnormal. ‘The fat-content seldom falls below 23 per cent or
rises above 7 per cent. The fat-content of milk from a whole
herd of cows varies only within comparatively narrow limits.
The following are the chief factors which cause the fat-content
of milk to vary:

(1) Individuality of cows.

(2) Breed of cows.

(3) Time between milkings.

(4) Manner of milking.

(5) Whether the milk is fore or after milk.

(6) Age of cow. ;

(7) Advance in lactation.

(8) Feed of cows.

(9) Environment.

(10) Condition of cow.

1. Individuality.—Whether a cow will produce milk with a
high or low fat-content depends upon something that is inherent
in the individual animal. Cows in the same herd, under the same

74

VARIATION OF FAT IN MILK 75

conditions as to care, feeding, etc., will produce milk that differs
widely in this respect. The secretory organs of the mammary
gland are the large controlling factor, and these we cannot
change. Even in the same breed we find animals that differ
very widely, as the table below, compiled from complete records
by Eckles, will indicate. These are average yearly tests for the
highest and lowest testing animals in each breed.

Number | Highest Lowest
Breed of Per Cent | Per Cent
Cows of Fat of Fat
METS YScks ecicrsto eee 76 7.00 4.47
SINOMUNOAN 5 cocosccoae 25 4.31 3550
olStem= eee 40 Boil 2.60
!

2. Breed of Cows.—The different breeds of dairy cattle have
their distinctive “‘ breed characteristics,” and the most important
of these are the quantity of milk they produce and its richness in
butter-fat.

The Channel Island breeds—Jersey and Guernsey—are
noted for the high fat-content of their milk; the milking strain
of Shorthorns and the Ayrshire breed produce a milk of medium
richness, while the Holstein produces a milk somewhat lower in
fat content. As to quantity of milk produced the order reverses
itself.

For all the breeds, excepting the Milking Shorthorn, the
table which follows, giving the average production and composi-
tion of the milk of the different breeds, is based upon Bulletin 156
of the Bureau of Animal Husbandry of the U.S. Department of
Agriculture, which summarizes and digests the published reports
of all the American experiment stations upon this subject.

3. Time between Milkings.—Where cows are milked twice a

-day—the common practice in the United States and Canada—
the difference in the per cent of fat in the two milkings is quite
marked, if the intervals are very unequal. On the other hand, if.
the intervals are equal, or nearly so, the difference is not great.

76 VARIATION OF FAT IN MILK AND CREAM

AVERAGE COMPOSITION OF THE MILK OF DIFFERENT BREEDS

Yearly
Ried Milk Per Cent | Pounds pee
Yield, of Fat of Fat :
Solids
Pounds
JOrSGy tetris fis cists cle ryeneiee 5508 5.14 283 14.9
Guemseyven Vo ccau tars Bee aa 5509 4.98 274 14.2
sNSiAtes| Re pees PAU eae cer SIND eee 6533 Bows, 252 12.9
IO Stein ies acta 8 vy ee seurenenees 8699 3.45 300 12).
Milking Shorthorn............ 5500 4.00 220 13.0

Experiments made by Ingle bring these points out quite clearly.
Five cows were milked at 6 A.M and 3 P.M. during a period of
three weeks. The average fat-content of the evening’s milk
was 4.26 per cent, while that of the morning’s milk was 2.8 per
cent. Following this, for four weeks, the cows were milked at
5.30 A.M. and 5 P.M. and the average evening and morning tests
were 3.80 per cent and 3.18 per cent respectively. Even here
there was a difference of an hour in the length of the two inter-
vals, which would account, largely, for the difference in test. It is
claimed, however, that with equal intervals the evening’s milk will
test slightly higher than the morning’s milk. This is attributed
to greater activity of the fat-secreting cells when the cows them-
selves are more active.

Milking three times a day, as is the custom in Denmark,
increases, to some extent, both the quantity of milk produced
and the per cent of fat init. But the increase is not sufficiently
marked to induce the average farmer in America to adopt this
practice, except in the case of a cow which is an exceptionally
large producer.

4. Manner of Milking.—Milking should be done in such a
manner as to induce the cow to be sympathetic toward the
milker. Hand milking should be performed quickly, but not
roughly or in a way that will excite the animal or create discom-
fort. The hand should close regularly and quickly from above
downward, in such a way as to extract the milk quickly and
efficiently. The finger ends should not press into the teats

VARIATION OF FAT IN MILK rae

uncomfortably, nor should the nails come into contact with the
teat to the extent of irritating it. As will be seen in dealing
with fore and after milk, the milking must be done thoroughly
since the strippings are very rich in fat content.

There is a marked difference between milkers. On this point
we quote from Decker. ‘“ By looking over the milking records
of the University of Wisconsin, it was possible to pick out the
cows milked by a certain milker, for he could (or rather did)

Fic. 13.—The wrong way to milk cows. (From Glucose Sugar Refining
Catalogue.)

invariably get more and richer milk from the same cows than
when the cows were milked by other men.”’

5. Fore and After Milk.—The first milk drawn from a cow is
very low in fat content, containing just a few tenths of a per
cent of fat; while the last, the strippings, will test very high,
often up to 8 to to per cent.

Van Slyke of the New York Station analyzed the different
portions of the milk of a Guernsey cow, with the following
results: .

78 VARIATION OF FAT IN MILK AND CREAM

|
Pounds | Per Cent
of Milk of Fat

IMEC [HOMO 5 6G ococccocs 0004s 3.2 0.70
Second portion........... abate 4.1 2.60
sings pOntionee srr eeraieer ere 4.6 5 Bs
Kounthyportlonsee seen rene 5.8 9.80

The practical lesson to be drawn from this is that milking
should be done efficiently and completely.

6. Age of Cow.—As already pointed out, the richness of a
cow’s milk is very largely determined by heredity. She will not
produce rich milk during one lactation period and poor milk
during another. However, age has its influence. Normally
there is a marked increase, from year to year, in the quantity of
milk given, with a tendency to a slight increase in the fat-content,
until a cow reaches maturity. Then, in the ordinary course of
events, we may look for a gradual decline. The following is
quoted from Eckles, whose investigations were both extensive
and thorough: “On the average, a well-grown two-year-old
may be expected to produce 70 per cent, a three-year old 80
per cent and a four-year old go per cent of the milk and fat that
she will produce when mature.” ‘“ The average fat-content
remains practically constant from year to year, except that after
the cow is eight or nine years old the percentage of fat always
declines slowly and gradually with advancing years.”

7. Advance in Lactation—This is a factor that materially
influences both the quantity of milk produced and its fat-content.
When a cow freshens she will probably, if in reasonably good
condition, produce milk with a slightly higher per cent of fat in it
than there will be a little later. With this exception the quan-
tity of milk produced and the per cent of fat in it usually remain
fairly constant during the first three or four months, after which
there is a gradual decline in the quantity of milk produced and a
steady increase in its richness. But cows differ very widely in
the rate of increase in the fat-content of their milk as they
advance in their lactation period. The following table gives the

VARIATION OF FAT IN MILK 79

records of two cows in the same Canadian herd, both of which
freshened in the spring and at practically the same time—also
the average for fourteen cows at the Geneva Station:

Cow No. 1 Cow No. 2 Geneva (14 cows)
Month
Gs Pounds | Per Cent | Pounds | Per Cent | Pounds Per Cent
of Milk of Fat of Milk of Fat of Milk of Fat
I 546 3-4 614 Bi3 753 4.02
2 618 3.4 704 BoD 780 2 WA
3 622 Sa5) 714 Boil 714 Syaqu
4 723 3-5 721 3.8 636 3.84
5 714 377 693 Aca 588 3.87
6 636 3-9 627 4.4 594 3.90
7 601 4.0 591 4.6 570 3.94
8 540 Ala it 502 5-1 480 3.890
9 427 A at 461 5.3 375 3.92
Io 214 4.2 47 7.6 282 4.1¢
TOTS Pere SSNS carats alt seats arcane rel mi eereaenee Nea. inane eee 168 4.58

8. Feed of Cows.—There was at one time a very general
belief, which still has its advocates, that the per cent of fat in
milk varies with the nature of the food the cow receives; but
many investigations made both in America and in Europe have
shown that, practically speaking, the richness of a cow’s milk is
not influenced by her food. A narrow ration, one made up
quite largely of concentrates rich in protein, will stimulate the
milk flow, a fact which is well known and made use of by those
experienced in the fitting and feeding of cows for high official
records; but it does not increase the per cent of fat in the
milk.

Observations by the Copenhagen (Denmark) Station over a
period of ten years, and including about 2000 cows, led the
observers to conclude that foods high in protein content may
possibly raise the fat-content of the milk to the extent of o.1
per cent—a very slight increase if actually an increase at all.
Lindsay of the Massachusetts Station found that a ration with a

80 VARIATION OF FAT IN MILK AND CREAM

large excess of protein stimulated the milk flow to the extent
of 15 per cent, but he concluded that the per cent of fat in the
milk is not influenced by the food a cow receives.

The addition of such abnormal foods as tallow, lard, palm
and oleo oils to a cow’s ration, or such a radical change of food
and environment as from stable to pasture conditions, may cause
a temporary change in the per cent of fat in a cow’s milk, but the
change is only temporary.

g. Environment.—Such unfavorable conditions as exposure
to inclement weather, sudden changes in temperature, and poorly
ventilated barns will cause a decrease in the milk flow. Experi-
enced cheese and butter-makers have noted a very serious falling
off in the output of their factories within a comparatively short
time, when the cows were exposed to low temperatures and cold
storms. Under continued exposure to unfavorable environment
there may be, at first, a temporary increase in the per cent of fat
in the milk.

Reasonable exercise, under suitable weather conditions, is
favorable to both health and a large production, but excess of
exercise is not desirable. Where cows are confined to the stable,
without exercise, the production may be quite satisfactory, but
these conditions are detrimental to the health of the animal and,
in the authors’ opinion, are contributory to the spread of tuber-
culosis ina herd. In Denmark it is the common practice to keep
the cows closely confined, without exercise, during the winter
months, and tuberculosis is very prevalent amongst the herds of
that country.

To secure the best results we must study the comfort of the
animal, and under the head of comfort we include favorable
temperature, clean healthful surroundings and the avoidance of
rough treatment and excitement.

10. Condition of Cow.—If a cow be in a high state of flesh
when she freshens, her milk will test much higher during the first
few weeks than it otherwise would. Investigations made by
Professor Eckles of Minnesota University bring this point out
very clearly. We submit the following table based upon work
done by him:

VARIATION OF FAT IN CREAM 81

Time after No. 207 No. 217 No. 300
Calving
Days Per Cent Per Cent Per Cent
2 5.8 4.4 4-5
5 | 4.8 4.2 4.2
Io | 3.9 205 4.1
15 | 3-2 3-7 3-9
20 2.5 3-4 3.6
Months
3 2.6 3.0 3.6
6 ® Ah aa 8 4.0
9 3-0 3-4
12 BoB Aleit
| Aver. for Year 2.8 3.4 Bess
|

Compare the first part of this table with that of the preceding
table in connection with “‘ Advance in Lactation Period.”’

On the other hand, Eckles found that when a cow begins to
put on flesh there is the very opposite tendency, namely, for the
per cent of fat in her milk to decline.

PART II

VARIATION OF FAT IN CREAM

The percentage of fat in cream delivered to creameries or for
city trade varies considerably from day to day, and a great deal
of dissension arises from the fact that the producer does not always
understand all the factors that are responsible for this wide
variation. .

Extensive work has been done by Professor O. F. Hunziker,
Purdue University, and similar work has been carried on at the
Danish Experiment Station at Copenhagen. ‘The work done at
Purdue and other experiment stations plainly and conclusively
shows that there are a great variety of factors and conditions
which control the richness of cream. These factors influence the
richness of the cream before it leaves the farm and cannot be

82 VARIATION OF FAT IN MILK AND CREAM

controlled by the creameryman, who receives the eream after it
has been separated. It is physically impossible to produce
cream of exactly the same richness from different skimmings
under the gravity method of creaming. It is impossible to so
operate the spoon, ladle or skimmer as to remove the same
amount of skim-milk with the cream each time. Where the
skim-milk is drawn from the bottom of the can it is equally
impossible to so gage the operation as to leave cream of the same
richness in the can at each skimming. Gravity cream, or cream
obtained by gravity skimming, is sure to vary in richness, and it
is not difficult for the producer to realize the causes of variations
under this method of creaming. It is more difficult, however,
to convince him that the richness of the cream will vary where the
small centrifugal or farm separator is used. The separator is one
of the most perfect pieces of farm machinery in use, and is
accordingly expected to do nearly perfect work. It is only
reasonable that the user of the small centrifugal machine will
expect to produce a uniform quality of cream; hence, when he
sells this cream and finds that the test is not the same as it was
on the previous day he suspects that something is wrong. ‘The
small farm separator does produce the same richness of cream
from different skimmings, provided that it is adjusted properly,
that it is operated in strict accordance with directions which
accompany it, and that the richness, condition and temperature
of the milk, and the proportion of water or skim-milk used in
flushing the bowl to the amount of milk separated, are the same.

The following are the chief factors which influence the per cent
of fat in cream:

(x) Cream screw adjustment.

(2) Richness of milk.

(3) Rate of inflow.

(4) Speed of machine.

(3) Temperature of milk.

(6) Amount of water or skim-milk used to flush the bowl.

1. The Cream Screw.—The richness of the cream obtained
from any farm separator is primarily determined and regulated

VARIATION OF FAT IN CREAM 83

by the cream screw. The centrifugal separator has two main
outlets, namely, the skim-milk outlet located near the periphery
or outer wall of the bowl, and the cream outlet, located near the
center of the bowl.

When the milk enters the revolving bowl it is separated into
_two layers, the skim-milk and the cream. The skim-milk, being
heaviest, is thrown against the walls of the bowl where it escapes
through the skim-milk outlet. The cream is drawn toward the
center of the bowl, where it rises and is discharged through the
cream screw or cream outlet. The cream screw is a small
threaded bolt with a very minute opening. This bolt can be
turned so as to move the opening nearer or farther from the cen-
ter of the bowl. When turned toward the center it delivers
richer cream, because a smaller proportion of the milk is taken
as cream. When turned out from the center it delivers thinner
cream, because a larger proportion of the milk is taken as cream.

2. Effect of Richness of Milk on Richness of Cream.—The
richer the milk, the richer will be the cream. With the cream
screw set to deliver a certain and definite richness of cream and
all other conditions normal, the separator will deliver a definite
ratio of skim-milk and cream. ‘This ratio varies according to the
way the cream screw is set. Under average conditions it may be
about 85 to 15; that is, for each 100 pounds of milk separated
the separator delivers 85 pounds of skim-milk and 15 pounds of
cream. If all conditions are the same, this ratio of skim-milk
to cream remains constant. Changes in the richness of the milk
cannot alter the proportion of skim-milk to cream delivered.
No matter how rich or how poor the milk, each 100 pounds
of milk will yield 85 pounds of skim-milk and 15 pounds of
cream.

But because practically all of the fat goes into the cream, the
cream will contain more fat from the separation of rich milk
than from that of thin milk. This fact is graphically illustrated
in Fig. 14.

The illustration (Fig. 14) conclusively shows that, all other
conditions being the same, 3 per cent milk produces 20 per cent
cream, 4.5 per cent milk produces 30 per cent cream, and 6 per

84. VARIATION OF FAT IN MILK AND CREAM

cent milk produces 40 per cent cream. Changes in the richness
of milk cause changes in the richness of the cream. Any condi-

EFFECT OF RICHNESS OF MILK UPON THE CREAM

100 LBS. OF 3% MILK 100 LBS. OF 4.5% MILK 100 LBS. OF 6% MILK
CONTAINS 3 LBS. OF FAT | CONTAINS 4.5 LBS. OF FAT | CONTAINS 6 LBS, OF FAT

SKIM-MILK

15 LBS. OF CREAM=3 LBS. OF FAT|15 LBS. OF CREAM =4.5 LBS. OF FAT| 15 LBS.OF CREAM=G LBS.OF FAT
TEST OF CREAM =20¢% TEST OF CREAM=30% TEST OF CREAM = 40%

3 4.5 6
55x 100=20% 45 x 100=30% 45 * 100=40%

Fic. 14.

tion, therefore, that affects the richness of the milk will also influ-
ence the richness and the test of the cream.

Conditions that May Cause Changes in the Richness of the
Milk.—During the early summer months the milk is usually
comparatively low in butter-fat. This is caused by such factors
as the freshening of the cows, change from dry feed to succulent
pasture and a natural and inherent tendency of the cows toward a
decrease in the richness of their milk in early summer. Toward
fall and early winter the opposite is the case. The advanced state
of the period of lactation and the change from succulent to dry
feed cause the milk to become richer in fat. It is obvious, there-
fore, that in the fall and winter the cream test tends to be higher
than in spring and early summer.

Again, it frequently happens that even in winter there is a
sudden drop in the cream test. This may be due to the fact
that some of the cows yielding rich milk dry up or that some cows
come in fresh or a new animal may be brought into the herd.

The seasonal variations in the richness of the cream may be
reduced by turning out the cream screw a trifle in the fall and by
turning it in during the spring of the year.

VARIATION OF FAT IN CREAM 85

3. Effect of Rate of Inflow on Richness of Cream.—The
greater the amount of milk passing through the separator of a
definite capacity per hour, the thinner will be the cream.

The skim-milk outlet of the bowl is constant. It can dis-
charge so much skim-milk and no more. It offers the first avail-
able exit for the milk in the bowl. Since it is located at the
periphery of the bowl toward which the skim-milk is forced, it
discharges skim-milk. —

All the milk that flows into the bowl in excess of what the
skim-milk outlet can discharge, leaves the separator through the

EFFECT OF RATE OF INFLOW UPON RICHNESS OF CREAM

NORMAL INFLOW LARGE INFLOW SMALL INFLOW
300 LBS. OF 4% MILK 350 LBS. OF 47% MILK 270 LBS. OF 4% MILK
CONTAINS 12 LBS. OF FAT | CONTAINS 14 LBS. OF FAT | CONTAINS 10.8 LBS. OF FAT

255 LBS.

255 LBS, : 255 LBS.
SKIM-MILK :

SKIM-MILK 5 SKIM-MILK

45 LBS. CREAM CONTAINS 95 LBS. CREAM CONTAINS 15 LBS. CREAM CONTAINS
12 LBS. FAT 14 LBS. FAT 10.8 LBS. FAT

TEST OF CREAM =26.7% TEST OF CREAM=14.7% TEST OF CREAM =72%

12 es 14 = 10.8 =724%
gp * 100 =26.7% oe x 100 =14.7% ig * 100=72%

Fic. 15.

cream outlet or the cream screw. The cream outlet, being located
near the center of the bowl where the cream gathers, delivers
cream.

The cream outlet then serves as the overflow. The greater
the amount of milk running into the bowl in excess of the capacity
of the skim-milk outlet, the greater is the overflow, the more
milk will leave the bowl through the cream outlet and the thinner
will be the cream. If the separator is so adjusted that, under
normal conditions, each 100 pounds of milk produces 85 pounds of
skim-milk and 15 pounds of cream, a 300-pound capacity machine

86 VARIATION OF FAT IN MILK AND CREAM

will deliver 85 300+100 or 255 pounds of skim-milk and the
remainder, the overflow, will be cream. In this case the amount
of cream discharged will be 45 pounds (300—255=45). If the
separator is forced beyond its capacity, that is if more than 300
pounds of milk are run into the machine, the skim-milk dis-
charged remains the same and the cream discharged receives the
extra milk. Running 350 pounds of milk into the machine,
for example, causes the separator to yield 255 pounds of skim-
milk and 95 pounds (350—255=95) of cream. If the milk inflow
is reduced below the capacity of the cream, say to 270 pounds,
the skim-milk discharged remains the same (255 pounds) and
the cream discharged is 15 pounds (270—255=15). The effect
of these variations in the rate of inflow on the richness of the
cream is shown in Fig. 15.

The above diagram shows that almost any richness of cream
may be obtained from the same milk and the same separator
according to the amount of milk that flows into the bow] per hour.
A normal inflow produced 26.7 per cent cream, a large inflow
produced 14.7 per cent cream and a small inflow produced
72 per cent cream.

Even the fullness of the pan or tank from which the milk
runs into the bowl affects the richness of the cream. ‘The fuller
the tank the more rapidly will the milk flow into the bowl owing
to a few inches of additional pressure. If the tank is kept filled
to the brim the cream will be thinner than when the tank remains
only one-third full.

Every separator is equipped with a simple device called the
“Float ” to regulate the inflow. The float fits into the receiving
cup of the bowl. When too much milk flows into the bowl the
float rises and partly shuts off the outlet of the milk supply tank.
When too little milk runs into the bow! the float recedes and the
supply tank delivers more milk.

The simplicity of the float has had a tendency to belittle its
value in the mind of the average dairyman, with the result that
on many farms it is not used and has been discarded. Bearing
in mind the marked effect of the rate of inflow on the richness of
the cream it seems inconsistent to accuse the creamery of inac-

VARIATION OF FAT IN CREAM 87

curate testing when the separator float is a conspicuous part of
the scrap pile on the farm.

4. Effect of Speed of Machine on Richness of Cream.—The
speed of the revolving bowl produces the force—centrifugal force
which drives the skim-milk out of the bowl. The greater the
speed, the greater the centrifugal force and the more rapidly
the skim-milk leaves the bowl. An increase in the speed, there-
fore, forces more skim-milk through the skim-milk outlet.
This means less milk for the cream outlet and consequently

EFFECT OF SPEED UPON THE RICHNESS OF CREAM

NORMAL SPEED LOW SPEED HIGH SPEED

100 LBS. OF 4.4% MILK 100 LBS. OF 4.4% MILK 100 LBS. OF 4.4% MILK
‘CREAM CONTAINS 4.4LBS.FAT|ICREAM CONTAINS 241 LBS.FAT|ICREAM CONTAINS 44 LBS.FAT

10 LBS. CREAM CONTAINS 19 LBS. CREAM CONTAINS 7 LBS. CREAM CONTAINS
4.4 LBS. FAT 2.1LBS. FAT 4.4 LBS. FAT

TEST OF CREAM =44% TEST OF CREAM =11% TEST OF CREAM =63%

4.4 & 21, 400=11 44 x 100 =63
it x 100 = 44% atx 10 % 4 %

Fic. 16.

richer cream. A decrease in the speed forces less skim-milk
through the skim-milk outlet, more milk has to be discharged
through the cream outlet and the cream, therefore, is thinner.
These facts were established experimentally. A separator
was so adjusted that, when run at normal speed (60 turns of
crank per minute); it delivered 90 pounds of skim-milk and 10
pounds of cream. When the speed was lowered to 25 turns of the
crank per minute, the skim-milk outlet discharged only 81 pounds
of skim-milk, increasing the amount of cream delivered to 19
pounds. When the speed was raised to 75 revolutions per
minute, the skim-milk discharge increased to 93 pounds, reducing

88 VARIATION OF FAT IN MILK AND CREAM

the amount of cream to 7 pounds. The effect of these variations
of speed on the richness of the cream are shown in Fig. 16.

Fig. 16 demonstrates conclusively that high speed yields rich
cream and low speed vields thin cream. At normal speed, the
cream tested 44 per cent fat, at low speed 11 per cent fat, and at
high speed 63 per cent fat. The very low test of cream from a
low speed separation is, in part, due to the fact that a large
amount of fat (about one-half of the fat of the milk) is lost in the
skim-milk.

How to Run the Separator at the Right Speed.—The proper
speed is indicated on the crank of the machine. It varies from
about 40 to 60 turns of the crank per minute, according to the
make of the separator. Ifa separator is to yield cream of uniform
richness, it must be given the same speed at each skimming.
This is possible only if the operator times himself frequently,
counting the revolutions of the crank with watch in hand, or by
the use of a patent speed indicator. ‘The absence of this pre-
caution renders the work unreliable. The general tendency on
the part of the operator is to overestimate the amount of work he
puts into the machine; the machine is run at too low a speed.
Even the same operator may vary the speed very considerably
at different times, depending on his frame of mind and physical
condition. Again, where different persons operate the machine,
there can be but little uniformity of speed, unless each person
makes an effort frequently to count the crank revolutions by the
watch. The use of a gasoline engine or some constant power
will tend to give a more uniform cream than when the machine is
operated by hand.

5. Effect of Temperature on Richness of Cream.—The higher
the temperature the thinner the cream. The temperature
influences the rate of inflow. The warmer the milk the more
rapidly will it run from the supply tank into the bowl. Since
the capacity of the skim-milk outlet is fixed, the increased inflow
of the milk is discharged through the cream outlet, producing a
thinner cream. Experimental results showed that when the
separator was so adjusted as to yield 15 pounds of cream and
85 pounds of skim-milk from every 100 pounds of milk separated

VARIATION OF FAT IN MILK AND CREAM 89

at go° F., a drop in the temperature to 50° F., caused the
amount of cream delivered to decrease to 5.5 pounds and the
skim-milk to increase to 94.5 pounds. ‘These results are graph-
ically illustrated in Fig. 17.

The results expressed in Fig. 17 show that when the tempera-
ture of the milk is decreased below normal, the richness of the
cream increases. At go° F., the cream contained 26 per cent fat.
At 50° F. it contained 40 per cent fat. The increase in the test
of the cream from the cold milk would be still greater, if it were

EFFECT OF TEMPERATURE UPON RICHNESS OF CREAM

TEMPERATURE OF MILK 50°F.
100 LBS. OF 3.9% MILK

TEMPERATURE OF MILK 90-95 Ro
100 LBS. OF 3.9% MILK

CREAM CONTAINS 3.9 LBS, FAT . CREAM CONTAINS 2.2 LBS. FAT

15-BS./-CREAM|

40%

85 LBS.

SKIM- MILK

15 LBS. CREAM CONTAINS 3,9 LBS. FAT

5.5 LBS. CREAM CONTAINS 2.2 LBS, FAT

TEST OF CREAM =40%

2.2
5.5

TEST OF CREAM = 26%

$2 x 100 =26% x 100 =40%

Fic. 17.

not for the fact that at that temperature a large amount of fat
is lost in the skim-milk.

The Proper Temperature for Separation.—The best practical
temperature at which to separate the milk on the farm is about
go’ F. The milk is never in better condition for separation than
immediately after it is drawn. It then has a temperature of
about go° F. to 95° F. If the milk is allowed to cool to a much
lower temperature, as is the case in the winter, when the separator
is operated only once per day, or once in several days, it should be
warmed up to about go° F. before it is run through the separator;
otherwise there is bound to be a considerable variation in the
cream test and also an increased loss of fat in the skim-milk.

90 VARIATION OF FAT IN MILK AND CREAM

6. Effect of Amount of Water or Skim-milk Used to Flush the
Bowl.—The more water or skim-milk used to flush the bowl, the
thinner will be the cream.

At the conclusion of the separation there remains in the bowl
and in the cream-discharging pan a considerable quantity of
cream. In order to save this cream it is necessary to flush the
bowl with water or with skim-milk. If enough water or skim-
milk is used the cream remaining in the separator is flushed out
and discharged into the cream can.

The extent to which the cream test is lowered by flushing the
bowl! will depend on the amount of water or skim-milk used, the
manner in which it is added and the amount of milk separated.

If just enough water or skim-milk is used to thoroughly rinse
out the bowl and the pan or tank, the richness of the cream is
not materially changed. An excess of water or skim-milk may
cause a considerable decrease in the richness of the cream.

If the water or the skim-milk is poured into the supply tank
and is allowed to run into the machine gradually, most of it will
escape through the skim-milk outlet and the richness of the cream
will be changed but very little. If the water or skim-milk is
poured directly into the receiving cup of the bowl, with the float
discarded, it will run into the bowl much more rapidly and more
of it will get into the cream.

The smaller the amount of milk used for the separation, the
more the cream is thinned down by the flushing.

Experimental data show that the cream test may be lowered
from 1 to ro per cent according to the amount and conditions of
the flushing. Enough water or skim-milk has been used when
the cream discharge begins to appear watery. Hot water or
warm milk will drive the cream out of the bowl more quickly and
may produce a higher testing cream.

The Proper Richness of the Cream.—Too thin cream is not
satisfactory because it leaves but a small amount of skim-milk
for the use of the dairy farmer, it increases the cost of transpor-
tation, it sours and spoils more rapidly, it prohibits the use of a
reasonable amount of starter for ripening at the creamery, it
does not churn out exhaustively, and yields an excessive amount

VARIATION OF FAT IN CREAM 91

of buttermilk, augmenting the loss of fat and therefore reducing
the churn yield.

Too thick cream is undesirable because it may cause the sep-
arator to clog, it increases the loss in handling, it is difficult
to properly sample and interferes with the accuracy of the test.

The most satisfactory cream for butter-making is that which
tests about 30 to 4o per cent fat. It is desirable to produce
somewhat richer cream in summer than in winter to prevent
excessive souring in summer and difficult handling in winter.

Effect of These Factors upon the Skimming Efficiency of the
Separator.—The richness of the milk has no effect on the com-

pleteness of the skimming.

The richness of the cream, within reasonable limits, has no
effect on the completeness of the skimming. The skimming of
very rich cream causes a large loss of fat in the skim-milk in the
case of certain makes of separators, due to the clogging of the
. machine.

The Rate of Inflow Greatly Affects the Completeness of the
Skimming.—If more milk is run into the machine than the capac-
ity of the machine calls for, there is excessive loss of fat in the
skim-milk. If the rate of inflow is reduced below the capacity of
the skim-milk outlet, the separator delivers no cream at all.

The Speed of the Separator Greatly Influences its Skimming
Efficiency.—Excessive speed does not increase the completeness
of the skimming. Insufficient speed increases the loss of fat in
the skim-milk. A separator run at half speed may cause one-half
of the fat of the milk to be lost in the skim-milk.

The Temperature of the Milk Affects the Skimming Efficiency
of the Separator.—For all practical purposes a temperature of
go° F. causes efficient skimming. At lower temperatures there is
excessive loss of fat in the skim-milk.

The Amount of Water or Skim-milk used to Flush the Bowl

Regulates the Amount of Fat Lost in the Bowl and Pan.—TIf the
bowl is not flushed at all, or insufficiently, varying amounts of
fat may be lost. If the bowl is flushed until the cream discharge is
watery, most of the fat in the bowl and pan is recovered and
saved.

CHAPTER VIII

RECEIVING, SAMPLING, GRADING AND TESTING MILK
AND CREAM

Receiving and Grading of Milk and Cream.—The man who
receives and samples milk at a creamery should be accurate and
quick at figures, have ability to grade and select milk, and to
stimulate interest in the production of good milk. He should
also be able to reconcile and satisfy patrons. The method
employed in some creameries of allowing a boy with immature
judgment to weigh and sample milk should not be tolerated.
The person who weighs and samples milk and cream comes in
direct contact with the patrons. Therefore, he is a strong factor
in serving the best interests of the creamery. In many of the
best butter and cheese factories in the country the head maker
or manager in charge is usually found at the weighing can. This
gives him the opportunity of studying the raw material from which
he is expected to make a high grade of butter or cheese. Some
of our large central plants pay the highest salary to the man who
has the ability properly to grade the cream and prepare the
starters. This requires a fine sense of smell and taste, which is
not possessed by everyone.

The first step in the receiving of milk is to ascertain the quality
of the milk delivered by the patrons. It is now a recognized
fact that the best butter cannot be produced from defective or
abnormal milk or cream, no matter how many improved methods
are employed in the manufacture. In view of this fact, and of
the knowledge we now have of the transmission of undesirable
germs from one sample of milk to another, and also the probability
that some of the patrons will deliver poor milk, it is essential that
the milk or cream be graded when it is delivered at the creamery.

92

RECEIVING AND GRADING OF MILK AND CREAM - 983

In the grading of milk or cream, different methods can be
used for detecting abnormal milk: (1) through the senses,
taste, sight, and smell; (2) by the acid tests; (3) by the fermenta-
tion test; (4) by heating; (5) by the Babcock test and the lac-
tometer.

While all of these tests are applicable to the grading of milk,
only the first and a portion of the fifth are usually applied to
cream.

1. Detection of Abnormal Milk and Cream through the
Senses.— In order to detect the different kinds of defective milk
one must be endowed with acute senses of smell, taste, and sight.
When the milk is in a good condition, it has a pleasant smell and
sweet taste,and appears normal. ‘This applies equally to cream
with the exception that not all cream for butter-making is sweet.
If milk has a disagreeable smell and taste it cannot produce good
butter. As a rule, the quantity of defective milk brought into
the average creamery is much in excess of that of really perfect
milk. As a consequence it would not be practicable to separate
all the defective milk into one class and the perfect into another.
The question as to where the line should be drawn between the
good, medium, and very bad milk or cream, must depend
upon the judgment of the receiver, and in a great measure upon
the local conditions. Some of the creameries have no facilities
for handling different grades of milk, and some sell butter on a
market where no sharp distinction is made between good and
poor butter. Others have, through experience, satisfied them-
selves that under American creamery conditions it does not pay
to make too many grades, nor does it pay to grade too closely.
Two, or at the most three, grades of butter can at times be man-
ufactured in one creamery profitably. It is advisable to reject
sour and abnormal milk. If accepted, it should not be mixed
with the remainder of the milk, as it might contaminate all of it;
or, the sour milk might cause coagulation, and thereby clog up
the separators. Ifa can of milk is sour, but otherwise clean, it is
not necessarily unfit for the production of first-class butter. If
retained until after the sweet milk has been skimmed, it may be
run through the separator successfully.

94 GRADING AND TESTING MILK AND CREAM

2. The Use of Acid Tests.—Some creameries are now grading
the milk or cream according to the amount of acid it contains.
Mann’s and Farrington’s acid tests can both be used, but a more
rapid and convenient way is to use a solution prepared from Far-
rington’s tablets. The solution is prepared by dissolving the
tablet in warm water, using an ounce of water toa tablet. When
one part of this alkaline solution and one part of milk are mixed
together in a cup and the solution still retains a pink color, it shows
that there is less than .1 per cent acid in the sample tested. Ii
two parts of alkali and one part of milk are mixed and the mixture
remains pink, then there is less than .2 per cent of acid. If the
mixture becomes colorless, it shows there is more than .2 per cent
acid in the sample. If three measures of alkali to one measure
of milk are taken, and the mixture remains pink, there is less
than .3 per cent of acid, etc. By means of such a test the acidity
can quickly be determined.

The sample cups should be numbered to correspond with the
number of each patron. The results of the tests should be
noticed at once, as the action of the atmosphere affects the color.

The acid tests are of value in grading cream, as a sour sample
of milk or cream is either old or has been improperly kept and
handled. The number of grades of cream and milk and the max-
imum limit of acid each grade can contain, are factors which
must be decided according to local conditions, by the operator.

3. Use of the Fermentation Tests.—Curdled, ropy, red and
blue milk can, as a rule, be readily detected without the appli-
cation of a special test, but there are cases when a person’s
senses are not sufficiently acute to detect samples of milk con-
taining undesirable fermentations. Several instances have
recently come within the authors’ notice. A neighboring cream-
ery was infested with a peculiar fermentation that caused a very
rank flavor in the butter. The milk that came to the creamery
was carefully examined, but the source of the trouble could not
be located. The cause could not be ascertained without the use
of the fermentation test.

It is in such instances that a fermentation test is of special
value. As a rule, the trouble is first caused by milk from one

RECEIVING AND GRADING OF MILK AND CREAM 95

particular patron. This milk may appear to be normal, and yet
contain germs which are very undesirable for the manufacture of
the best quality of butter.

Fermentation Tests.—There are two tests which may be of
general use; namely, the ‘“ Wisconsin Curd Test” and the
‘““ Gerber Fermentation Test.” The former is used in cheese
factories, but the latter is to be recommended in testing milk for
butter-making.

Gerber Test.—The apparatus for this fest consists of properly
made glass tubes resting upon a rack which fits into a small
round tin tank, about two-thirds full of water. The temperature
of this water can be controlled by means of a lamp kept burning
underneath, or by the use of steam. ‘The milk delivered by dif-
ferent patrons is put into the glass tubes, and these are numbered
so as to indicate to which patron each belongs. The tempera-
ture should be kept at about 104° to 106° F. for about six hours.
Then the tubes are taken out, the milk shaken, and the appear-
ance, smell, and taste of the milk noted. The tubes are warmed
again for about another six hours, when they are again examined.
If any samples contain a preponderance of abnormal ferments,
the fact will usually appear in less than eighteen hours. If
milk does not coagulate in twelve hours, or become abnormal
in some way, it is considered good.

The special apparatus mentioned above is not absolutely
essential, nor is the temperature employed considered by the
authors to be the most suitable to give reliable results. Ordinary
sample jars can be used, instead of specially prepared tubes.
After the milk has been placed in the jars they can be kept in any
convenient place, at a temperature of about 98° F. The best
place to keep them is in a vessel containing water, the temperature
of which can be controlled.

Wisconsin Curd Test.—This test consists of taking some milk
in a jar and adding about ten drops of rennet, which coagulates
the milk. The sample is allowed to stand until the curd hardens,
when it is cut into small pieces with a case knife; the whey is
drawn off, and the curd allowed to stand at a temperature of
98° F. If there are any undesirable forms of bacteria present,

96 GRADING AND TESTING MILK AND CREAM

they will reveal themselves by developing small holes in the curd,
usually accompanied by a bad odor.

This test is a very ingenious one for cheese-making. In
butter-making the Gerber Fermentation Test, or a similar one,
is more convenient.

4. Grading Milk by Heating.—This test is not very much

Rd i lial ali

Fre. 18.—Troemner’s Babcock cream-testing scales.

used in creameries; but in cheese factories the heating of milk in
order to ascertain its suitability for cheese-making is practiced
to a considerable extent. The heating test. which is in common
use in Canada, consists of heating a small sample of the milk to be
tested to 120° F. If it will stand this temperature without coag-
ulating, it is considered to be good milk. If it coagulates when
heated to this temperature, it is too sour
to be used for cheese.

This heating may be considered an
acid test. When milk contains about
.3 per cent acid, it usually coagulates
Fee ae penn eves Bale when heated. It should be borne in

cock cream-testing scales, mind in this connection that different

samples of milk, containing exactly the

same amount of acid, do not coagulate at the same tempera-

ture. Some samples will coagulate upon heating when contain-

ing a little less than .3 per cent acid, while others will not
coagulate until more than .3 per cent acid has developed.

In practice the temperature (120° F.) is not always closely

RECEIVING AND GRADING OF MILK AND CREAM 97

adhered to. A small portion of the sample to be tested is put
into a tin cup, and the cup is put into hot water or over a jet of
steam. When the milk is hot its characteristics are noticed.

5. Use of Babcock Test and Lactometer.—These tests are
of special value in detecting watered or skimmed milk. When-
ever a sample of milk appears watery or blue, it is fair to presume
that water has been added. The test for specific gravity and the
test for fat can then be applied to such samples of milk. Asa rule
composite samples are taken daily at creameries, and the patrons

Fic: 20.—Acid carboy trunnion. Fic. 21.—Acid hydrometer.

paid according to the fat delivered. For this reason water adul-
teration is not very common at creameries, but is practiced to a
greater extent in the milk-supplies of cities. The use of the lac-
tometer in connection with the Babcock test has already been
referred to under the heading of “‘ Specific Gravity of Milk.”

The Babcock test is now in such general use in America for
determining the per cent of fat in milk and cream that no other
will be dealt with here. At one time the Oil-test Churn was used
quite exclusively for testing cream, but it has gone almost entirely
out of use.

98 GRADING AND TESTING MILK AND CREAM

The Babcock test always deals with weight. . For instance,
when we say that a sample of milk tests 4.0 per cert or that a
sample of cream tests 30.0 per cent, we mean that in 100 pounds
of the milk there are 4 pounds of fat, or in too pounds of the
cream there are 30 pounds of fat.

For the sake of convenience a sample may be measured into a
test bottle instead of being weighed, when the accuracy of the
result is not likely to be affected. Milk may be sampled for the
Babcock test with a pipette, because the specific gravity of milk is
always so nearly the same that the same measure of milk from
widely different sources has, for all practical purposes, the same
weight, and because milk is in such a liquid condition that it
neither holds air nor adheres to the wall of the pipette. Rich
cream, on the other hand, has a lower specific gravity than thin
cream; moreover, cream is SO syrupy or viscous in its nature that
it will hold air or other gas and stick to the wall of the pipette.
For these different reasons, the authors wish to state emphat-
ically, that when cream is tested for commercial purposes, as at a
creamery, it should never be measured but always weighed into
the test bottle. The measuring of cream for the Babcock test,
when this test is made for commercial purposes, is a fraudulent
practice; and in most of the States and Provinces of the United
States and Canada there are laws prohibiting it.

In taking the sample for a Babcock test of milk a 17.6 c.c.
pipette is used. This will deliver 18 grams of milk, the quantity
for which the scale on the test bottle is graduated to read per
cent of fat. To this we add 17.5 c.c. of sulphuric acid (specific
gravity 1.82-1.83), varying the quantity to suit the strength.
The contents are then thoroughly mixed by giving the bottle a
rotary motion. The acid acts upon and digests all the solids of
the milk, excepting the fat, and heats the sample to a desirable
high temperature. The bottle is then placed in the centrifugal
tester and whirled for five to six minutes, at a speed suitable
to the diameter of the machine, usually 800 to 1000 revolutions
per minute. The bottle is then filled to the bottom of the neck
with hot water (soft or distilled) and whirled for about two min-
utes. A second addition of hot water is then made to float the

RECEIVING AND GRADING OF MILK AND CREAM 99

fat into the neck to about the 8 per cent mark, after which the
sample is given a final whirling of one minute. The sample is
then set in hot water at 130°—140° F. to bring it to the right tem-
perature for reading. A pair of dividers is generally used for
measuring the fat column in taking the reading. With milk,
the reading is taken from the highest to the lowest point, that is,
the meniscus of the fat column is included.

th

PET

aT

an

AEE TC OT
ge

i=)

OO

o

Sy

~SUUIUTTUT

eas
Lege
s wn

Fic. 22. Fic. 23.

Fic. 25. Fic. 26.
Skim-milk Whole-milk Cream test- 9-gram cream Cream
test-bottle. test-bottle. bottle. test-bottle test-bottle

Babcock Test-bottles.

In the Babcock test of cream either a 9- or an 18-gram bottle
is used. The drift has been decidedly towards the use of the
bottle graduated to read per cent for g grams. A 9-gram sample
of cream is weighed into the bottle by means of a special cream
scale. To this are added about g c.c. of commercial sulphuric
acid, and the contents are mixed by giving the bottle a rotary
motion. When the action of the acid has proceeded far enough—

100 GRADING AND TESTING MILK AND CREAM

when the contents have reached a chocolate color—some hot
water is added to the test bottle to check the action of the acid.
The sample is then centrifuged for five to six minutes, after which
hot water is added to float the fat into the neck of the bottle;
then the sample is again whirled for two minutes. The reading
is taken at a temperature of 130°—-140° F., after a few drops of a
colored reader, composed of a light mineral oil with suitable
coloring matter in it, have been added to flatten the meniscus.
Dividers are used for measuring the fat column in taking the
reading.

_ There are three very common conditions which make it dif-
ficult to obtain a fat reading: (1) Black, charred, flocculent
matter is sometimes found at the bottom of the fat column. This
is commonly caused by using too much or too strong acid or by
mixing milk and acid at too high a temperature. The remedy
is to use less acid or to cool milk and acid before mixing. The
black charred matter may also be due to allowing the acid to
stand in contact with the milk too long a time before mixing or to
pouring acid through the center of the milk. (2) There may bea
layer of white flocculent matter at the bottom of the fat column.
In this case an insufficient quantity of acid may have been used,
the temperature of the milk and acid may be too low, or they
may not have been thoroughly mixed. The remedy is to use
more acid, to warm milk and acid before mixing, or to shake the
mixture thoroughly before whirling. (3) Occasionally there is a
layer of impure foam at the top of the fat column. This is gen-
erally due to the use of hard and impure water. The remedy is to
use pure distilled hot water. For more detailed information on
this subject see “‘ Testing Milk and its Products,” by Farrington
and Woll.

Does the Babcock Test, as Ordinarily Applied to Cream, Give
too High a Reading?—An investigation made by Harry B. Sieg-
mund, Analyst, Hendler Creamery Company, and R. Sewell
Craig, Senior Food Chemist, City Health Department, Balti-
more, resulted in a decision that the Babcock test of cream, as
ordinarily conducted, gives too high a reading. The following is
a brief summary of the results obtained:

BABCOCK TEST OF BUTTERMILK AND SKIM-MILK 101

When the centrifuging was done in a thirty-six bottle, elec-
trically driven machine, run at a speed of rooo revolutions per
minute, the average of the tests of a number of samples of cream
was 1.0 per cent higher than that obtained by gravimetric analy-
sis (Rose-Gottlieb test); and where the test was made with a
twenty-four bottle steam-turbine machine, run at a speed of 800
revolutions per minute, the average test was 1.5 per cent too
high.

With the electrically driven machine run at a speed of 1200
revolutions per minute the reading was o.6 per cent higher than
that obtained by the Rose-Gottlieb test.

When an electrically driven machine, run at a speed of 1600
revolutions per minute, was used, the Babcock test and the Rose-
Gottlieb test gave practically the same results.

The conclusion was that with machines run at the lower
speeds a little water, or water and acid, remains suspended in the
fat, and that it requires the force created by the higher speed
machine completely to separate this from the fat.

Babcock Test of Buttermilk and Skim-milk—The American
Association Test.—In an exhaustive investigation of the losses
of fat in buttermilk, conducted by Professor J. W. Mitchell
under the direction of the senior author and not yet completed,
several points have come prominently to the fore.

The first of these is that the losses of fat in buttermilk, in
our creameries, are much greater than they are generally sup-
posed to be. Many creameries, under their methods of testing,
are getting tests of .1 per cent to .2 per cent fat for their butter-
milk. Of between 250 and 300 complete records, made by
Professor Mitchell and the author, of churnings at different
creameries, not one showed a Babcock test as low as .2 per cent.
Of course the test was rigorous, but even this was considerably
below the chemical analysis.

The second point is that there are a large number of factors
which influence the per cent of fat in the buttermilk, such as
length of time taken to churn, temperature of cream, length of
time the cream is held at churning temperature, condition of
cream, fullness of churn, speed of churn, etc. This means that

102 GRADING AND TESTING MILK AND CREAM

every creamery has its own conditions and problems to meet, and
consequently should be in a position to determine, readily and
accurately, what its losses of fat in the buttermilk are. It will
then be in a position to study how to reduce them.

The third point is that the average creamery, under its
methods of testing, is not aware of what its losses are. It is not
uncommon to note, in creamery records, tests of .1 per cent to
.2 per cent for the buttermilk, whereas it is known, from hun-
dreds of analyses made in the laboratory of the American Asso-
ciation of Creamery Butter Manuiacturers, that the average
loss exceeds .5 per cent fat. The loss does not fall far short of a
pound of butter to every hundred pounds of buttermilk.

Realizing the necessity for a simple test that would corre-
spond closely with chemicai analysis for buttermilk (or skim-
milk), and that could be operated by anyone capable of conduct-
ing a Babcock test, the senior author asked Professor Mitchell to
devise such a test, if possible. In his efforts he has fortunately
been very successful.

The different methods of making a Babcock test of butter-
milk, including the new modification of the same, are briefly out-
lined below.

The following method of testing buttermilk (or skim-milk)
has been in use for many years, and is still more generally used
than any other. A double-necked skim-milk bottle, graduated
to read as close as .o1 per cent for 18 grams, is used. Most of
the bottles read up to .25 per cent—some to .50 per cent. After
the buttermilk is well mixed, a 17.6 c.c. pipette is used to transfer
18 grams of it to the test bottle. To this is added 20 c.c. of
commercial sulphuric acid (sp. gr. 1.82-1.83). The acid and milk
are then thoroughly mixed by giving the bottle a gentle, rotary
motion. Care must be exercised, in mixing, to avoid choking
the small neck and causing some of the contents to be thrown
out through the large neck. The bottle is then placed in the
centrifuge and whirled at full speed for about five minutes.
Hot water (soft or distilled) is then added to the bottle to fill it
almost to the neck and the machine is again run for one or two
minutes. Hot water is then added to float the fat into the small

AMERICAN ASSOCIATION TEST 103

neck and the bottle is again whirled for one or two minutes.
The bottle is then placed in hot water at a temperature of 130°—
140° F., after which the reading is taken. It is advisable to use a
pair of dividers to measure the fat column. Under this method
the reading will be very low—possibly .1 per cent to .2 per cent
when it should be .4 or .5 per cent.

A More Rigorous Test.—A modification of the foregoing is to
take a 9-gram sample by means of a 9g c.c. pipette, that is, a
half sample. To this is added about 12 c.c. ofa fairly strong acid,
well up to a sp. gr. of 1.83. The whirling is done in a very high-
speed machine and is greatly prolonged—fifteen to twenty min-
utes the first time, about ten minutes at the second whirling, and
about five minutes at the third whirling, or thirty to thirty-five
minutes in all. The reading must be doubled, since only a 9-gram
or half sample is taken to a test. This method will probably
double, or more than double, the result. But even under
this method the test falls considerably below the results secured
by chemical analysis.

The American Association Test.—A close study of the dif-
ferent practical methods for the quick determination of the per
cent of fat in milk and its products and by-products reveals
the fact that there is a general principle running through them
all, that is, there are three factors which operate in all of them.
These are (1) the use of one or more chemicals to liberate the -
fat, (2) the heating of the contents of the test bottle in order
to liquefy the fet, and (3) the application of centrifugal force.
Where sulphuric acid is the chief or only chemical used it gen-
erates sufficient heat, through its strong affinity for water; but
where it is not used at all or is used very sparingly it becomes
necessary to heat the sample in hot water before centrifuging it.

A number of useful tests have been devised for the quick
determination of the per cent of fat in milk, etc. The following
are a few of the most outstanding of these:

(t) The Lactocrite, devised in 1886 by Dr. De Laval, inventor
of the cream separator which bears his name. The chemical
used was concentrated or glacial acetic acid, containing 5 per
cent of concentrated sulphuric acid. It was necessary to heat

104 GRADING AND TESTING MILK AND CREAM

the sample before centrifuging it. This was a pioneer test but is
not now in use.

(2) The Babcock test, invented by Dr. Babcock of the Wis-
consin Experiment Station and published in July, 1890. This
test is so widely and favorably known and is in such general
use, especially in America, that it seems unnecessary to do more
than refer to it. It is simple, speedy and accurate, and the cost
of a test is small, a single, cheap chemical, commercial sulphuric
acid, being used.

(3) The Gerber test, brought out in 1892. In this test two
chemicals are used, viz., commercial sulphuric acid and amyl
alcohol. It is used quite extensively in Europe.

(4) The Sinacid Butyrometer. This test was devised by
Sichler of Germany in 1904. No acid is used in the test, hence
the name “ Sinacid.”” The chemicals used are sodium hydrox-
ide, Rochelle salt and iso-butyl alcohol. It is necessary to heat
the samples by placing them in hot water before centrifuging
them.

All of these tests were designed primarily for the testing of
milk and such milk products as cream, and for this purpose
they are reliable; but in testing the by-products of the dairy,
skim-milk and buttermilk, they all give results that fall con-
siderably below those obtained by chemical analysis (the Rose-
Gottlieb test). No doubt this is the main reason for the failure
there has been to make a thorough study of the losses of fat in
buttermilk and how to overcome them. Hence, when the
American Association of Creamery Butter Manufacturers began
its study of losses of fat in buttermilk it was confronted with
the problem of devising a suitable test for the accurate deter-
mination of the per cent of fat in buttermilk,

Trials were made of different combinations of chemicals,
such as, sulphuric acid and amy] alcohol, sulphuric acid and iso-
butyl alcohol, and sulphuric acid and normal butyl (z-butyl)
alcohol. After extensive experiments had been made sulphuric
acid and z-butyl alcohol were selected as the most suitable
combination to use, and for the following reasons:

(1) The results, with duplicate tests, are exceptionally uni-

AMERICAN ASSOCIATION TEST 105

form and correspond closely to chemical analysis (The Rose-
Gottlieb test), as the accompanying table shows.

(2) There is much less trouble with a deposit in the test
bottles than is the case where the other alcohols are used.

(3) Normal butyl (7-butyl) alcohol, being a single alcohol
that is readily purified, is free of impurities while the amyl and
iso-butyl alcohols are not likely to be. In blank tests made,
that is, when water was substituted for buttermilk in a test, a
short column of some impurity rose into the neck of the test
bottle when the amyl and iso-butyl alcohols were used, but not
when 2-butyl alcohol was used.

(4) The m-buty] alcohol is quite stable and is not at all likely
to be attacked by the sulphuric acid, while the other alcohols
mentioned are iso-alcohols that run off into chains and are less
stable and are likely to be mixtures.

(5) The z-butyl alcohol does not possess either a pungent or
an otherwise offensive flavor or odor, and consequently is much
pleasanter to use than the others.

(6) The z-butyl alcohol is the lowest in price of the dif-
ferent alcohols, and, being stable and free of impurities, is the
most reliable alcohol to use. Even the cheaper grade of this
alcohol (the ‘ practical”) contains no impurity excepting pos-
sibly a slight amount of moisture.

Extensive and carefully conducted investigations have
shown that the right amounts of commercial sulphuric acid
and n-butyl alcohol to use in testing a 9-gram sample of
- skim-milk or butter-milk are as pen in the directions which
follow:

Directions for making a test:

Chemicals.—Commercial sulphuric acid.

Normal butyl alcohol.

1. Place the chemicals and buttermilk in the test bottle in
the following amounts and the order indicated.

(a) 2c.c. of n-butyl alcohol.

(b) 9 c.c. of buttermilk.

(c) 7 to 9 c.c. of commercial sulphuric acid.

Vary amount of acid to suit its strength. The right amount

106 GRADING AND TESTING MILK AND CREAM

is being used when the fat column is golden yellow to light amber
in color.

2. Mix contents of bottle thoroughly.

3. Centrifuge for six minutes.

4. Add hot water (soft or distilled) to fill bottle to bottom
of neck, and whirl for two minutes.

5. Add balance of water to float fat into neck and again whirl
for two minutes.

6. Read at temperature of 130° to 140° F. Double the read-
ing to obtain per cent of fat.

7. In cleaning test bottle—especially if there be any deposit—
first add a small amount of lukewarm water and to this add
sulphuric acid. Always add the water first and then the acid—
never the reverse. Rinse the bottle well with this mixture and
then rinse with hot water.

This test gives results corresponding to those of chemical
analysis.

A test bottle, with a scale reading up to .50 per cent for 18
grams, should be used.

The following table, comparing the Babcock, The American
Association Test, and Rose-Gottlieb (Chemical) tests, is sub-
mitted.

Babcock Test ! The American Rose-Gottlieb
Association Test | Test
Per Cent Per Cent Per Cent
38 552) 52
34 47 47
40 57 59
43 .60 60
36 54 53
39 aS Oe 59
36 .50 52
34 .50 48

1 The Babcock test given in the foregoing table was that obtained from using
12 c.c. of sulphuric acid with a 9-gram sample and centrifuging, in all, about
chirty-five ninutes in a high-speed tester.

PER CENT OF FAT IN BUTTER KO?

Determination of the Per Cent of Fat in Butter.—The methods
for the determination of the per cent of fat in butter may be
classified under two heads, viz., ;

(r) Scientific methods, such as

(a) The Extraction method.
(b) Rose-Gottlieb method.
(c) Indirect determination of fat.
(2) Practical methods, such as
(a) The 00 per cent bottle designed by Hepburn for use
in the Babcock test.
(6) The Shaw test.

Scientific Methods.—TYhe scientific methods are too com-
plicated and require too long a time for their completion to be of
practical use in a creamery.

The Rose-Gottlieb method may be briefly outlined as follows:

This method, which was originally designed for the estima-
tion of fat in milk, can be used with advantage also for the deter-
mination of fat in butter.

According to A. Hesse,! about 2 grams of butter are weighed
out into a 3 cm. long, half-cylindrical glass tube, or simply
wrapped in a piece of stiff fat-free paper of the same form. The
tube or paper and the contained fat are then introduced into a
Gottlieb cylinder, and hot water is added until the 1o-cm. mark
is reached. If the butter does not melt, the cylinder is placed in
warm water until it does. Then 1 c.c. of ammonia and to c.c.
of 95 per cent alcohol are added, exactly as in the estimation of
milk-fat. If the mixture is still warm, the cylinder is cooled in
cold water so that the ether which is to be added will not evap-
orate too quickly. The cooling must not, however, be carried
too far; otherwise the butter will become solid again. Twenty-
five c.c. of ether are then added, and the contents of the cylinder
mixed by repeatedly inverting it. Afterwards 25 c.c. of petro-
leum ether are added and the mixing repeated.

After the different layers have separated quite sharply from
one another, the clear ether-fat solution is siphoned off in the
usual way, the lower opaque layer not being disturbed. Then

1 Molkerei-Zeitung, Hildesheim, 1903, No. 27.

108 GRADING AND TESTING MILK AND CREAM

50 c.c. of ether are poured into the cylinder and at once siphoned
off without being mixed with the other liquid. Finally, the
residual liquid is shaken with a mixture of 25 c.c. ether and 25 c.c.
petroleum ether, and, after settling, the ethereal layer is drawn
off. The three portions of ether are naturally all placed in
the same tared flask, which is weighed again after the ether has
been evaporated and the fat dried.

These repeated extractions with ether and petroleum ether
are necessary if exact results are to be obtained. If the above
directions are carefully followed, it will be found that the Rose-
Gottlieb method, while easier and more convenient, and also
considerably quicker than the extraction method, gives results
which are in very close agreement with those obtained by the
latter.

The Mojonnier test is a modification of the foregoing, and
possesses several features which greatly facilitate the work and
shorten the time required to make the test. In the method
known as the “ Indirect Determination of Fat,” the percentages
of moisture, casein and salt are carefully determined. ‘These
are then added together and their total is subtracted from too to
determine the per cent of fat in the butter.

Practical Methods.—There are several practical methods that
are made use of to a greater or less extent. We shall briefly
outline two of these.

For making a Babcock test of butter, using the Illinois 9-inch,
g-gram, go per cent butter test bottle devised by Dr. N. W.
Hepburn, University of Illinois, the following directions are given:

“ Taking the Sample——In testing butter it is necessary to
exercise great care both in securing and in preparing the sample.

“ Sampling from a Churn.—With an ordinary ladle cut off
the surface of the butter in several places, including each end and
the middle of the churn. Then make a composite sample by
taking, with a spatula or common case knife, a small sample
(10 to 20 grams each) from six or eight different places in the
churn where the surface has been removed, putting them into
an 8-ounce wide-mouthed glass-stoppered bottle.

PER CENT OF FAT IN BUTTER

109

“ Sampling from a Tub.—Draw one or two triers from the
full depth of the tub and drop the entire plug of butter into the

glass-stoppered bottle.

“ Preparing the Sample for Testing.—Place the glass-stoppered
bottle containing the sample in warm water, shaking vigorously
every few seconds until it is thoroughly mixed and is about the
consistency of heavy cream, when it is ready to be weighed into

test bottle. CAuTION.—Be careful not to get
the sample too warm nor in too liquid a condi-
tion. If this happens place it in cold water,
shaking very frequently, until the sample takes
on the desired consistency. Samples should not
pour freely, but like thick cream or paste. Little
heating and thorough shaking is the rule for suc-
cess in preparing the sample.

“ Weighing the Sample.—Balance the bottle
on the scales and weigh out a 9-gram sample by
the method used in weighing cream samples.
(Scales as sensitive as moisture-test scales
should be used.)

“Adding Acid.—First add about 9 c.c. of
water then 17.5 c.c. of sulphuric acid. CaurTION.
—Add the acid slowly and in small portions,
shaking after adding each portion to avoid
foaming. High-salt samples are most likely to
foam. If foaming occurs, vigorous shaking will
often prevent the loss of the sample. After the
sample is thoroughly mixed with the acid and is
dark brown in color, add warm water, filling the
test bottle up to the base of the neck.

““Whirling.—Place the test bottles in the
tester and whirl for ten minutes; stop, fill with
water to bring the fat up in the graduated neck,
and whirl again for five minutes.

“ Reading.—Set the test bottle in water at
140° F., covering the fat in the neck, and

Fic. 27.—Illinois
9 inch, 9 gram,
90 per cent
butter test
bottle.

allow it to stand for at least five minutes; then read. In read-

110 GRADING AND TESTING MILK AND CREAM

ing, cut off all the upper curve on the fat column or add a
couple of drops of white mineral oil (glymol) to destroy the
meniscus.”

THE SHAW TEST FOR FAT IN BUTTER
APPARATUS REQUIRED

‘* Babcock centrifuge or tester.!

“ Shaw separatory funnels.

‘Balance which is sensitive to 0.01 gram. (A torsion bal-
ance, such as is used in testing for moisture, will answer if it is
in good condition.)

“ Accurate set of metric weights.

Fic, 28.—Separatory funnels used in the Shaw test.

“ Glass cylinder graduated at 9 and 11 c.c.

“ too-c.c. glass beaker.

“ Wooden rack for holding separatory funnels.

“ Support for separatory funnels on balance.

“Tn addition to the above a special socket to hold the separa-
tory funnels will be required. As shown in the cut, this differs
in no material way from the socket ordinarily used in the Bab-

1. F. Nafis.

PER CENT OF FAT IN BUTTER 1d

cock centrifuge, except for the opening in the side. It may
easily be adapted from the ordinary socket or if preferred the
socket may be sent to us and we will make the necessary changes
for a nominal charge. Care must be taken that the capillary
stem of the funnel does not project far enough through the hole
in the socket to strike against the side of the centrifuge while
being whirled. It is a good plan to fit a disk of rubber gasketing
in the bottom of the socket.

SAMPLING THE BUTTER

“In the determination of fat in butter, great care must be
taken in securing a representative sample and in preparing this
for the test.

“Several samples from different parts of the tub or churn
should be taken with a butter trier. These are placed in a suit-
able container, such as a 1-pint Mason preserve jar or a cup,
which is placed in water at about 100° F. The sample is then
mixed with a spatula or spoon until about the consistency of
thick cream. ‘The sample must not be left any length of time in
open containers, since some of the moisture will evaporate.
Should the sample be kept for any reason for a day or two
before it is mixed, it should then be placed in warm water (with
the cover on the container) until melted, and then cooled while
being vigorously shaken until it solidifies. The reason for this is
that on standing some of the water will ooze out and cannot be
reincorporated except by emulsifying and cooling while in this
condition. ‘Too much stress cannot be laid on careful sampling
and mixing the sample, for upon this the accuracy of any deter-
mination in butter very largely rests.

DETERMINING THE FAT

“Tt will be found more economical in some cases if four or
multiples of four determinations are made at once. In this case
the two double sockets containing the funnels will balance when
placed opposite in the centrifuge. If but one or two determina-
tions are to be made it will be necessary to balance the centrifuge
by putting weights in the opposite socket. First of all, the clean

112 GRADING AND TESTING MILK AND CREAM

and dry separatory funnel must be weighed, and this as well as the
other weighings involved must be done with care. This weight
once found will suffice for all determinations made with that par-
ticular funnel, unless by accident some of the glass should be
chipped off. A slight scratch made with a file can serve to iden-
tify the funnels. A paper Jabel should not be used. If requested
at the time of ordering we will number them without additional
charge.

‘“‘ Bach time, before using the separatory funnels, they should
be lubricated with a properly prepared stopcock lubricant which
we supply with directions for its use.

“1. Weighing the Charge.—Counterpoise the small beaker
on the balance and carefully weigh out 20 grams of the sample
mixed as directed.

“II. Transferring the Charge to the Separatory Funnel.—
Place the beaker containing the charge on a radiator or steam
pipe until the butter is melted. (This may also be accom-
plished by adding a small quantity of boiling water.) Next
pour the charge into the funnel kept in an upright position in the
wooden rack. No part of the charge must be lost in transferring. »
With a fine stream of hot water rinse down the sides of the
beaker and pour the rinsings into the funnel. (If the salt is to
be determined, distilled water must be used. See directions
under ‘ Salt Test.’) Repeat this, using not more than a tea-
spoonful of water at a time until the funnel is full to within
about one-quarter of an inch of the shoulder. The rinsing can
be done very conveniently with the arrangement on many steam
centrifuges for filling the Babcock test bottles, i.e., the rubber
tube ending in a glass or metal point and connecting with a water
tank heated by steam. The point must be fine, however. Should
it be larger than three-sixteenths of an inch, it can be replaced
with the tip of a small oil can. Should this arrangement not be
at hand, one can easily be improvised from a tin can, a rubber
tube, and an oil-can tip. In transferring the melted butter
and rinsings, the last drop may be prevented from running down
the outside of the beaker by touching the lip of the beaker to the
neck of the separatory funnel.

PER CENT OF FAT IN BUTTER 113

“II. Centrifuging.—Insert the separatory funnel in the
special socket, allowing the stem to project through the hole in
the bottom and the handle of the stopcock through the open side.
CavutTion.—The socket must always be placed in the centrifuge,
with the open side facing the direction in which the wheel revolves.
This is very important, if the opening faces the reverse direction
the stopcock will be thrown out and broken. Whirl one minute
at the same speed used in testing milk with the Babcock test.
The centrifuge must be kept warm.

“IV. Removing the Water.—Remove the separatory funnel
from the socket and allow the water to flow through the stopcock
until the fat (or curd) is within one-eighth of an inch of the stop-
cock. In this and later operations involving the stopcock one
must be sure it does not stick. It must always be under control,
and it is best to give it frequent slight movements when the water
or acid is running through it to be sure that this control is main-
tained; otherwise it might stick at a critical moment and the
determination be lost. The most of the salt and part of the curd
are taken out by the water. The remainder of the curd and all
of the fat stays in the funnel. [If it is desired to determine the
salt, this wash water is allowed to run into a 250 c.c. flask and the
operation described in this paragraph conducted three times
instead of but once, the wash water being added each time to
the flask.

‘Tt sometimes happens that the water will not start flowing
when the stopcock is opened, in which case it can be started by
blowing into the mouth of the separatory funnel.

“ V. Dissolving the Curd.—Measure out 9g c.c. of cold water,
preferably condensed steam, with the glass graduate and pour
into the beaker. Add to this 11 c.c. of sulphuric acid of the same
strength used in testing milk and cream (specific gravity, 1.82-
1.83) and mix by gently shaking. (CAurion.—Always add acid
to water and not water to acid, or a serious accident may result.)
While still very hot add the mixture to the contents of the separa-
tory funnel. Now dissolve the curd by giving the funnel a
circular motion with the hand grasping the neck. Centrifuge
one minute, as before. Draw off the acid solution till the fat

114 GRADING AND TESTING MILK AND CREAM

layer is within about one-fourth of an inch of the stopcock and
repeat the operations in this paragraph.

“VI. Freeing the Fat from the Acid Solution.—The fat will
now be in a clear transparent layer free from curd, and the solu-
tion below it will be practically colorless. ‘To separate these two
draw off the latter until the fat nearly reaches the stopcock and
centrifuge another minute. Now allow the fat to come down
through the stopcock till it just reaches the end of the capillary
stem. This last step offers no difficulties, providing the stopcock
is kept in control, but it requires care. If desired, the acid may
be colored with methy] orange.

“VII. Determining the Percentage of Fat.—Carefully dry
the separatory funnel on the outside with a clean soft cloth and
weigh it. The weight thus obtained minus the weight of the
empty funnel represents the weight of butter-fat in 20 grams of
the sample. The percentage is obtained by multiplying by s.

“ Often it is possible to obtain a clear fat layer with but one
addition of acid, but in some cases it will be found necessary to
add it the second time, as directed. The test for fat alone
involves 4 centrifugings of one minute each. The centrifuge
should be kept warm and the contents of the funnel in a melted
state when the acid is added. The time consumed should not be
longer than it takes to test cream with the Babcock test, and the
operations involved are simple and easily learned. No difficulty
will be experienced in obtaining a clear fat. Occasionally there
will appear a slight emulsion at the bottom of the fat layers
when the fat is drawn into the stem. This is so small in amount
that it does not seem to affect the accuracy of the test to any
considerable extent. The emulsion should be weighed as fat and
considered as such.

CLEANING THE SEPARATORY FUNNELS

‘“‘ The separatory funnels should be washed after each deter-
mination, but it is not necessary to dry them before use, providing
their weight, when clean and dry, has been found. The cleaning is
easily done with hot water and either soap or cleansing powder.
They should be well rinsed off with clean water and drained.”

115

GRADING AND TESTING MILK AND CREAM

Ce

-

Kirschbraun & Son, Omaha, Neb. One of the largest

FIG. 29.—Churn room.

the world.

in

1€S

and finest creamer

f the first prize co-operative creamery at Carroll, Iowa.

Fic. 30.—Street view o

116 GRADING AND TESTING MILK AND CREAM

Very few of the creameries have, as yet, begun the regular
determination of the per cent of fat in their butter, most of them
confining their work on the composition of butter to determina-
tions of the per cent of moisture and the per cent of salt. The
three constituents of butter outside the fat, are moisture, salt
and curd; and where a uniform system of manufacture is adopted,
and the churning is done under right conditions and the butter
well washed, the curd content is not likely to exceed 1 per cent

Fic. 31.—The oil-test churn.

or vary more than half a per cent. Consequently accurate
determination of the moisture and salt-contents enables a
creamery to estimate, very closely, the per cent of fat in the
butter. ;

Sediment Test.—Milk should be free from sediment and
foreign insoluble material. Producers of the raw material are
not always conscious of the necessity of producing clean milk,
and of the effects of impurities upon the finished products.

Sediments may be seen on the bottom of a glass jar after the

NECESSITY OF GOOD. MILK IL

milk has stood quietly for several hours. The better way of
showing these sediments is to use the Wisconsin Sedimentation
Test. The container for this test holds about one pint of milk.
A screw cap fits over the top. By means of a small air pump,
pressure can be applied and the milk forced through a disk or
filter. This disk is removable and the filtered-out dirt on the
surface can thus be shown.

Necessity of Good Milk.—All authorities agree that the best
grade of butter and cheese cannot be made from sour or tainted
milk. The two countries renowned for the excellence of their

Fic, 32.—Wizard tester. Fic. 33.—Twentieth-century hand tester.

dairy products—Denmark and Canada—owe their success
largely to the purity of the milk from which these products are
made. Makers who have won for themselves national reputa-
tions in cheese- and butter-making have almost invariably been
men who insisted on getting first-class milk, The method of
classifying milk and cream and paying for each according to
quality has been adopted by some creameries.

The authors do not hesitate to say that cream whose flavor
is such as to show that it is in a putrefactive or decomposed
condition should be rejected as unfit for making an article of
heman food. While it is advocated by some that it should be

118 GRADING AND TESTING MILK AND CREAM

received, made into butter and sold on its merits, the wisdom
of this is to be questioned. Cream that is simply off in flavor is a
different proposition. This may, in justice and fairness, be
taken in on its merits and paid for accordingly. The practice
of receiving and paying for cream indiscriminately is something
which should be condemned and discouraged. The authors have
come in contact with many patrons in different parts of the
country and have yet to meet the first patron who would seri-
ously object to taking his milk or cream home when thoroughly
convinced that its condition was such that it should not be
received. Patrons, as a rule, respect the maker who keeps his
creamery in a good sanitary condition and insists upon being
supplied with a good quality of milk or cream. It should be the
aim of every creameryman to make the highest grade of butter
possible, and thus be in a position to take full advantage of a dis-
criminating market, for this is the kind of market that pays the
highest prices.

Sampling of Milk.—The sampling of milk and cream for fat
tests is one of the most delicate problems with which the creamery
operator has to deal. If a proper sample is not obtained, the
ultimate test will not be correct, no matter how carefully the
succeeding steps may be carried out. There are two methods of
sampling in use: First, sampling with a small dipper, and
second, sampling with a sample-tube, or milk-thief. The
sampling of milk for composite samples should be done ‘every
day, and the samples taken should represent the average quality
and form a certain proportionate part of the milk or cream
delivered.

In order to get a sample which represents the average quality,
the milk or cream delivered must be thoroughly stirred, so as
to get an even distribution of the fat.

In order to get a proportionate part of the milk or cream
delivered from day to day, it is necessary to use a sampling-
tube.

The sampling of milk and cream with a dipper for composite
samples has been in use for a long time, and is still practiced to
quite an extent. However, it is fast becoming recognized that

SAMPLING OF MILK 119

the use of a suitable sampling tube is much better. It takes a
more representative sample of a can of cream, whether it be for
the making up of a composite sample or for the testing of an
individual shipment. In the case of composite samples of both
milk and cream it takes an aliquot portion, or one in proportion
to the quantity of milk or cream delivered. The difficulty at
one time in sampling cream—and particularly thick cream—
with the sampling tube was that the only opening in the tube
was at the bottom, and the cream would not flow into it as the
tube was lowered. However, this trouble is completely over-
come when a sampler like the McKay sampler is used. This is
made up of two tubes, an inner and an outer, and a plunger
(see cut). Both the tubes have openings up the side. Before
inserting the sampler in a can of cream, the outer tube is turned
on the inner so that the openings are not opposite each other, or
so as to close the sampler, and the plunger is drawn back. The
sampler is then lowered into the cream to the bottom of the can,
when it is opened momentarily to allow it to fill and is then closed
again. In emptying the sampler the outer tube, which is the
shorter of the two, is drawn up a little to leave an opening at the
bottom, and the plunger is pushed down to force the cream out of
the tube. In doing so it cleans the tube completely. This style
of sampler does equally efficient work whether used in a
creamery or cream station, or in taking samples on a cream
route.

An investigation made by the American Association of Cream-
ery Butter Manufacturers showed the dipper method of sampling
cream to be unreliable. In this investigation the cream in the
can was first hand-stirred—no less than forty vigorous double
strokes being used—and then sampled with a dipper, after
which a sample was taken by means of a McKay or tube sampler.
In all, thirty-two lots of cream were sampled and tested in this
way, and the following short table gives some of the results
secured:

120 GRADING AND TESTING MILK AND CRIAM

Babcock Test of

Sample | Times Se STH

Nov ulSuced Condition of Cream ; Difference
Dipper Tube
Sample | Sample
Per Cent
I 50 Viscous, not very smooth....... 41.0 44.0 3.0
2 40 SOLOO Parc Gl tewie Llewaetlee relat: 4.0 i) BO. Ons
3 65 Heavy on top, liquid below, lumpy| 42.5 38.5 4.0
4 60 Viscous but good condition...... 34.5 23.5 1.0
5 44 @wite ligule are ee XO). 24.5 2.0
6 60 Viscous, slightly lumpy......... 40.5 40.5 0.0
7 75 Top fair, bottom almost solid,
MNO oot ON anieameedc eben ms Wreaiin ears 47.5 38.5 9.0
8 50 Good condition................ 40.5 30.5 1.0

While the difference in the test of the samples under the two
methods was usually not great, yet the dipper method of sampling
proved unreliable.

Sampling-tube.—At creameries where milk is received, the
sampling-tube, or milk-thief, gives the best results and satis-
faction. It is very difficult in practice to get a proportionate
sample with a dipper, from day to day. To illustrate: A patron
who delivers 200 pounds of milk testing 3 per cent fat one day
may on another day deliver too pounds of milk testing 5 per cent
fat. Ifa dipperful is taken from each for a composite sample, the
test of that composite sample will be 3+5+2, or 4 per cent.
According to this test, these 300 pounds of milk delivered wilt
contain 12 pounds of butter-fat. In reality 6 pounds of fat were
delivered in the 200 pounds, and 5 pounds of fat in the 100 pounds,
making a total of rz pounds of fat. Thus we see that the dipper
method is not reliable, and in this case the patron was paid for
1 pound of butter-fat too much for the two days’ delivery. If
the sample taken from the 200 pounds of milk had been twice as
great as that taken from the 1oo pounds of milk, then the com-
posite test would have been perfect, no matter whether it had
been taken with a dipper or with a sampling-tube. If the same
weighing-can is used every day, it is possible to maintain an

SAMPLING TUBE 121

XS

Fic. 34.—Vat room. Kirschbraun & Son, Omaha, Neb. One of the largest
and finest creameries in the werld.

= a ry st
"INTERIOR of CREAMERY, STRAWBERRY Pow, in
273, : ac

eeu Es : wank pio ge S. Nd

Fic. 35.—Interior of creamery, Strawberry Point, Iowa. One of the largest
whole-milk creameries in the U.S.

122 GRADING AND TESTING MILK AND CREAM

exact proportion for a sample by always putting the sampling-
tube perpendicularly into the milk at the same place in the weigh-
ing-can, and by exercising care in other respects.

When the cream is being collected from different patrons
by a hauler, a milk-thief often works unsatisfactorily. This is
especially true during cold weather. A cream tube similar to
the one shown in the accompanying illustration is more effective.

Fic. 36.—The McKay cream and Fic. 37.—Cream
milk sampler. sampling-tube.

The way in which the tube is used is apparent from the figure.
If a certain patron has 40 pounds of cream, the cream is filled
to the 40 mark on the scale of the tube; if he has 30 pounds, it is
filled to the 30 mark, etc.

Sampling Churned Milk.—It occasionally happens that ne
milk arrives at the creamery slightly churned. This is espe-
cially the case during the summer. Usually such milk is sam-
pled in this condition, but if it is desired to find the percentage of
fat in such milk in its unchurned condition, it is essential to melt

SOUR AND COAGULATED MILK 123

the churned fat before sampling. If the butter has been churned
into a few large lumps, these lumps can be taken out in a pan, or
pail, with a comparatively small amount of milk, and this
heated until the butter has melted. This is then remixed with the
milk from which it was first taken and sampled while it is being
stirred.

The churning of the milk during transit is mainly due to
two things: First, to a high temperature of the milk (65° to
85° F.) and second, to hauling partly filled cans a long distance
over rough roads. If the temperature of the milk is low (about
50° F.), when it leaves the producer, there is seldom any danger
of having churned milk at the creamery.

Frozen Milk.—When milk is cooled to 31° F., or below, it
freezes. Ice forms near the sides and bottom of the can, until
a funnel-shaped cavity filled with milk is left in the center.
According to both Richmond and Fleischmann, the icy por-
tion contains more water than the unfrozen milk, and the
unfrozen portion is rich in solids. According to Farrington,
when 25 per cent of the sample of milk was frozen, the icy
portion contained about 1 per cent less fat than the original
portion. When about half of it was frozen there was no great
difference in the fat-content of the frozen and unfrozen parts.

In practice, however, freezing seems to have a different effect.
When a can full of partly frozen milk is sampled at the creamery,
the unfrozen milk nearly always contains less fat than the original
sample. This can be accounted for by opening the can of milk
and noting the amount of frozen cream on the sides near the top.
Whether the unfrozen portion contains less or more fat than the
original depends, therefore, upon conditions. At any rate,
frozen milk has a composition different from that of the original
sample. On this account an accurate sample cannot be had,
unless the frozen portion be first completely melted and well
mixed with the remainder.

Sour and Coagulated Milk.—In order to get a fair sample
from a can of sour and coagulated milk, it must be stirred
very thoroughly, so as to bring the coagulated milk into a
uniform emulsion. A better sample can usually be obtained

124 GRADING AND TESTING MILK AND CREAM

with a dipper. If the milk is not too thick, a fair sample can be
obtained by the use of the sampling-tube. In order to reduce
a can of coagulated milk to a thoroughly uniform quality, it is
best to pour it from one can into another. This mixes it much
more completely than if the sample were simply stirred with a
dipper or any other kind of an agitator.

Apportioning Skim-milk——The amount of skim-milk to be

Fic. 38.—Jensen can drier, sterilizer and rinser.
(Jensen Creamery Machinery Co.)

received by the patron depends largely upon the thickness of
cream skimmed, and upon the amount of skim-milk retained at
the creamery for various purposes. The amount of skim-milk
generally returned by creameries varies between 80 and go per
cent of the whole milk delivered.

Most up-to-date creameries now make use of skim-milk
weighers. Where such are employed, the man who receives the
milk hands each patron a check for the amount of milk delivered.
This check is put into the skim-milk weigher, and it allows an

WASHING CANS 125

amount of skim-milk to flow out, corresponding to the number of
pounds indicated on the check.
In case a skim-milk weigher is not employed, it is essential

ima ee

Fic. 39.—Hydraulic can washer and dryer. (Creamery Package Mfg. Co.)

to have a man at the skim-milk tank to weigh out the proper
amount of skim-milk to each patron. If the patrons are allowed
to weigh out their own skim-milk, mistakes are frequently made,
which result in more or less dissatisfaction. It is quite customary

for butter-makers to
draw a chalk line on
the outside of the can
some distance below
the surface of the
milk. This indicates
the point to which the
can may be filled with
skim-milk.
Washing Cans.—
The creamery oper-
ator should make it
a point to have all
empty cans thorough-
ly washed with warm
water, and then
steamed and_ steril-

Fic. 40.—Hydraulic can washer-rotary type.
(Rice and Adams.)

ized, after which hot air should be blown through thoroughly to
dry the cans. Frequently, bad flavors are transmitted to cream
from cans that have been closed up tight before being thoroughly

126 GRADING AND TESTING MILK AND CREAM

dried. Where hot air is not used, the cans can be turned
upside-down on a platform with openings to allow air to circu-
late through the cans, drying them thoroughly before the covers
are put on.

Drying cans as above described not only conserves the tin
of the cans, but also places the cans with the patrons in a clean
condition, free from bad odors. It also saves considerable
work on the part of the patrons, as well as insuring them a clean,
sanitary can.

One patron told the author that this cleaning of the can was
worth one cent per pound of butter-fat to him. The creamery
is equipped to do this can-cleansing better than is the patren
and it is repaid for this extra labor in a better grade of cream
and in increased patronage.

CHAPTER IX
COMPOSITE SAMPLES

Definition.—In order to avoid testing each patron’s milk or
cream every day for fat, a small sample, which represents the
average quality and a proportionate part of the whole, is taken
from each patron’s milk every day and placed ina jar. A pre-
servative of some kind is previously placed in the jar to keep the
contents from spoiling. ‘This is called a composite sample.

When to Sample.—Some makers prefer to sample the milk or
cream delivered every day; others prefer to sample every other
day. Some creamery operators, again, sample four or five times
in succession at intervals, the patrons being unaware of the time
when the sampling is to take place. The most reliable and prac-
tical method, however, is to take a sample every day, and test it
for fat at the end of every two weeks. When cream is received
composite samples do not give reliable results. In fact this
system has been very generally superseded by that of weighing
and testing the cream of each delivery or shipment.

Kind of Preservatives to Add. While there are several pre-
servatives that may be used, such as salicylic acid, borax, boracic
acid, and bicarbonate of soda, those most commonly used are
bichromate of potash and corrosive sublimate (mercuric chloride)
either singly or as a mixture. Bichromate of potash, while
poisonous, is not extremely so and it imparts a color to the sample
which readily indicates its presence. It has, however, two
defects; if used in excess it is very much inclined to cause a
charred or burnt reading when the sample is tested, and if the
sample be exposed to light for any length of time a leathery scum
forms on the surface, which it is difficult to dissolve completely
by means of the sulphuric acid.

127

128 COMPOSITE SAMPLES

Corrosive sublimate is a strong and a very satisfactory
preservative; but it is quite poisonous, and where the powder
itself, which is white, is used in composite samples some kind of
coloring matter should always be added to indicate its presence.

According to the authors’ experience, corrosive sublimate
tablets can be highly recommended. The tablets contain a
color, which, when dissolved, colors milk, so that it can readily
be distinguished as not being fit for human food. The tablets are
very poisonous, but are more
efficient in their preservative
effect than bichromate of
potash. They can be ob-
tained Jrom any creamery-
supply house.

During the winter, when
the samples are kept com-
paratively cold, less perserva-
tive is needed than in the
summer. One corrosive sub-
Fic. 4t.—Composite samples and rack to limate tablet will keep a

hold sample jars. half-pint to a pint of mille
or cream in good condition for about two weeks in summer,

and about three weeks in winter, providing the sample is properly
cared for. Some makers are practicing testing at the end of
every month during the winter, and every two weeks during the
summer. ‘Testing at the end of every month saves labor, but it
is not a reliable method to follow under all conditions, as some of
the samples are likely to be somewhat impaired after standing
so long.

Arrangement of Composite Samples.—Pint glass jars with
covers are, so far as known, the most convenient vessels to use
for composite samples. Shelves should be arranged in the weigh-
ing-room on which to keep the bottles. If possible, it is best
to have them in a case closed with glass sliding doors. This
is neat, and, if the glass doors fit well, the samples are in some
measure protected in case of quick, unexpected changes in tem-
perature. ‘These sliding doors should be locked when the cream-

CARE OF COMPOSITE SAMPLES 129

ery operator is absent from the creamery, in order to prevent any
tampering with the composite samples.

The best method of arranging the sample jars is to have all
the jars belonging to the patrons of each route standing in
one group, or on one shelf, if possible. The bottles are num-
bered to correspond with the number given each patron on the
milk sheet. ‘The name of the hauler, or the number of the route
can be put on each shelf. ‘The samples belonging to those who
haul their own milk can be put on another shelf; these can be
designated as individual haulers. Such a classification, when the
bottles are plainly numbered, will often prevent the mistakes that
are likely to occur if the bottles are simply numbered and put
into a rack together.

Care of Composite Samples.—In the first place, the jars
should be kept scrupulously clean. ‘The tests are unreliable if
the jars are left covered with milk and molds round the neck
from one month to another. When the samples have been
tested the jars should be thoroughly cleaned, and, if necessary,
scalded, before they are used again. Care should be taken to
spill as little milk as possible around the neck, inside as well
as outside of the bottle, when the sample is put in. If the
milk is spilled there, it gives the bottle an unattractive appear-
ance. Very often it becomes moldy, and, as more milk is added
and the sample shaken every day, this mold gradually extends
down the sides of the bottle. This causes the composite sample
to be infested with undesirable growth, and to spoil sooner than
it would if greater care were taken in keeping the milk from
coming in contact with the sides of the bottle before coming
in contact with the preservative.

A few drops—but only a few—of formaldehyde added to the
sample, where this is necessary, is a good preventive of mold;
but this should not be used as a substitute for thorough cleaning
of the bottles after each test period.

It is important also that the sample jars be well covered;
otherwise the moisture evaporates, causing the milk or cream
to dry up, and, making the test unreliable by increasing the per
cent of butter-fat. A gentle rotary motion should be given each

130 COMPOSITE SAMPLES

jar when a sample is added to it to mix the cream, which rises to
some extent after the milk has stood a while.

Average Sample.—It is sometimes desirable to obtain an
average test of the milk from a whole day’s delivery. This can
be obtained in two ways: First, by taking a sample from each
patron’s milk with a sampling-tube, and putting all the samples
together in one jar. The result represents an average test, pro-
viding the samples have been correctly taken. Second an aver-
age test can be had by boring a small hole in the conductor-head.
When the milk passes over this hole, a small portion of it drops
through. A vessel of some kind can be put underneath to catch
the drops. Such a drip-sample will represent very accurately
the average quality of the milk received at the creamery. If it is
desirable to keep this sample, a preservative can be added to it.

Composite Sampling without the Use of Preservatives.—
Pipettes can be obtained holding 5.87 c.c. of milk. These are
one-third the size of the ordinary 17.6 c.c. pipette used for the
Babcock test. With this small pipette a sample may be taken
every day from each patron’s milk, during three successive days,
and emptied into the same test-bottle each day. At the end of
three days the samples may be tested and the bottles cleaned,
ready for use again.

Accurate composite samples may be obtained in this way,
providing the sample in the pipette is correctly taken each day.
No preservative is needed. The preservatives are added to the
composite samples to prevent curdling. The test-bottles may
be placed on a shelf, or preferably in a rack made to hold them.
They should be marked in such a way as to identify them.
A good way is to mark them as the composite jars are marked,
the number on the test-bottle corresponding to the number on
the milk-sheet for each patron.

CHAPTER X
CREAMERY CALCULATION

Find the Average Per Cent of Fat.—In calculating the average
per cent of fat from a number of cows, or the milk furnished by
the different patrons, the mistake of adding the tests of all the
samples together and dividing the sum by the total number of
samples tested is often made. Milk from different patrons, or
from different cows, will always vary, both in quality and in
quantity, and in order to get a correct average test, both quan-
tity and quality must be taken into consideration. The wrong
way of calculating the average percentage may be illustrated as
- follows:

Sample Milk Delivered| Per Cent Fat
I 50 lbs. 5.0
2 100 4.5
3 500 BO
4 300 3-5
4) 16%
4

The average test, according to the wrong method =, per cent.

The correct way of calculating the average percentage may
be illustrated as follows:

The average test, according to the correct method, is 3.42
per cent.

It will be seen from the example quoted that there is a differ-
ence of more than .5 per cent. If the percentage of fat or the

131

132 CREAMERY CALCULATION

Sample Milk Delivered Per Cent Fat
I 50 lbs. 5.0= 2.5 lbs. fat
2 100 4.5= 4.5
3 500 3.0=15.0
4 300 3-5=10.5
950 lbs. 950)32.5 lbs. fat
Bene

number of pounds of milk is uniform, it does not matter which
of the two ways illustrated above is used. But as uniformity

Fic. 42.—A Russian co-operative creamery in Siberia.
(U. S. Government Bulletin.)

in either of these respects scarcely ever exists in practice, the only
correct way of calculating the percentage is to find the total
number of pounds of fat and divide it by the total number of
pounds of milk; the result is .0342, which may be written 3.42
per cent.

CALCULATION OF OVERRUN 133

It is very common for creamery patrons to test the milk
from each of their cows, then add the tests together and divide
by the total number of cows tested. The result they will
call the average test, and frequently such tests are made use of
as evidence against a creamery operator to prove that his tests
at the creamery were not correct. The fallacy is evident from
what has been said above.

The same mistake is also likely to be made in finding the aver-
age test from several creamery-plants and skimming-stations.

Calculation of Overrun.—The amount of overrun is the dif-
ference between the amount of pure butter-fat and the amount
of butter manufactured from that given amount of fat. This
difference, divided by the amount of fat and multiplied by roo
will give the percentage of overrun. The calculation of the
overrun in the creamery should always be made from the fat-
basis on which the patrons are being paid. Ii the fat is delivered
in the cream, the overrun should be calculated from the fat in
the cream. The overrun calculated from the composition of the
butter manufactured would not be an indication of the correct
overrun, as there might be serious losses of fat sustained during
the different steps in the manufacture, such as from inefficient
skimming, incomplete churning, and general losses in the cream-
ery. It is possible that butter might show a high content of the
substances not fat, and yet not show a good overrun on account
of losses; while butter containing only a medium high moisture-
content might show as great or greater overrun on account of
thorough and efficient work during the different steps of manu-
facture.

The amount of overrun depends upon:

1. Thoroughness of skimming.

2. Completeness of churning.

3. General losses in the creamery.

4. Composition of the butter manufactured.

The theoretical overrun, however, may be quite accurately
calculated from the composition of the butter manufactured
in a well-regulated creamery. In creameries where the condi-
tions of separation and churning are almost perfect, the amount

134 CREAMERY CALCULATION

of fat lost in the buttermilk and the skim-milk is quite constant
from day to day, and should not exceed .1 per cent in the skim-
milk and .2 per cent in the buttermilk, according to the Babcock
test. Basing the calculations upon the above figures, the theo-
retical overrun may be calculated from the composition of the
butter as follows:

If, for instance, we start with 1000 pounds of milk testing
4 per cent fat, there will be a total of 40 pounds of fat. If we skim
32 per cent cream trom 4 per cent milk, we should have 3%, or 4
of it cream, and the remainder skim-milk, or 125 pounds of
cream and 875 pounds of skim-milk. Jf there were .1 per cent
of fat in the skim-milk, there would be a loss of .875 pound of
fat during skimming. There would then be 39.125 pounds of fat
in the 125 pounds of cream (40—.875 =39.125). If 10 per cent of
starter were added to the cream we should get 137.5 pounds of
cream testing 28.4 per cent. (125 pounds cream X1.10= 137.5
pounds cream; 39.125+137.5X100=28.4 per cent fat.) By
churning this cream we should obtain about too pounds of butter-
milk. Ifit tested .2 per cent fat there would be a loss of about .2
pound of fat, making a total loss of fat in skim-milk and butter-
milk of 1.075 pounds. Subtracting this total loss of 1.075 from 4o
pounds we would have 38.925 pounds of fat left to be made into
butter (40—1.075=38.925 pounds of fat). If the butter on
analysis proves to contain 82 per cent fat, the total number of
pounds manufactured will be 38.925 + .82 = 47.47 pounds of butter.
47.47 —40=7.47 pounds theoretical overrrun, and 7.4740 X 100
= 18.7 per cent overrun (theoretical).

It is evident that the losses of fat will vary according to the
different conditions. The richer the cream, and the less fat in
the whole milk to be skimmed, the more skim-milk there will be;
the thinner the cream and the more fat there is in the milk to be
skimmed, the less skim-milk there will be, and consequently
with the same skimming efficiency less fat will be lost in the skim-
milk. The thinner the cream is the more buttermilk there will
be. These conditions must be left for the operator to govern
according to the conditions present.

The actual amount and per cent of overrun as determined

WHAT SHOULD THE OVERRUN OF CREAMERY BE? 135

in creameries is calculated as described previously. The formula
is as follows:

Butter — fat

a XIoo=per cent of actual overrun.

Calculation of Churn-yield.—Instead of expressing the
increase of butter over that of fat in the percentage overrun,
as above, it is often customary among creamerymen to speak
of the “‘ churn-yield.” For instance, they say that their test was
3.90, and their churn-yield was 5, meaning that on the average
each roo pounds of milk contained 3.9 pounds of fat and yielded
5 pounds of butter. The churn-yield is always expressed in per-
centage, and is obtained by dividing the total pounds of butter
obtained by the total pounds of milk from which the butter was
made, according to the following formula:

Pounds of Buttes
Pounds of milk

X 100 = churn-yield.

In case cream is handled instead of milk, the same may be
obtained by substituting “ pounds of cream ”’ for ‘‘ pounds of
milk ”’ in the formula.

What Should the Overrun in a Creamery Be?—In discussing
this problem we shall take 80 per cent as the legal standard for
fat in butter. If every churning of butter were to drop to this
standard, but none below it—a thing quite impossible of attain-
ment—if the patrons were credited with all the fat the creamery
received, and if there were no mechanical losses, and no fat in the
buttermilk, then every 80 pounds of milk-fat received would -
make 1oo pounds of butter; that is, too pounds of fat would
make 125 pounds of butter, or, the overrun would be 25 per cent.

The creamery has some gains and some losses which tend to
offset each other.

The gains come mainly from two sources, namely, (1) a small
fraction of a pound of cream on some, but not all, of the cans of
cream. (2) A small fraction of a per cent of fat on some, but not
all, of the cream tested.

136 CREAMERY CALCULATION

In weighing cream half-pounds should be credited, and in the
Babcock test of the cream readings should be made by half and
not whole per cents, thus 30.0 per cent, 30.5 per cent, 31.0 per
cent, etc., and not 30.0 per cent, 31-0 pet cent, etc.

Following out this principle, the average gain in weight,
per can of cream, will not exceed a quarter of a pound, and the
average gain in per cent of fat will not exceed 0.25 per cent.

The losses may be enumerated as follows:

(1) The Loss of Fat in the Buttermilk.—This will, under present
conditions, easily equal 0.5 per cent. Our extensive investigation
of the losses of fat in buttermilk, including complete records of
several hundred churnings in different creameries, shows this to
be a very conservative estimate; and tests of hundreds of samples
of buttermilk in the laboratory of the American Association of
Creamery Butter Manufacturers fully support this estimate.

(2) Losses in Packing —Enough butter must be put into a
package to insure its having the proper weight when it reaches
the market.

(3) Mechanical losses, due to cream adhering, to a small
extent, to the different utensils—cans, vats, etc. Under this
head may be included the occasional spilling of small quantities
of cream.

(4) If practically all of the butter is to come up to the standard
of 80 per cent fat, the average per cent of fat in the butter will
exceed this a little.

(5) If the results of the investigation made by Siegmund
and Craig, are to be accepted as correct, the Babcock test of
cream, as ordinarily conducted, gives a reading that is a little
high. Their findings are summarized in the chapter on “ Receiv-
ing, Sampling, Grading and Testing.”

As a basis for estimating what the overrun in a well-con-
ducted creamery should be, an 8-gallon can of cream will be taken
as an average shipment and it will be assumed that the creamery,
in weighing and testing the cream, credits the patron with 65.0
pounds of cream testing 30.0 per cent, whereas the actual weight
of the cream is 65.25 pounds, and the actual test of the cream is
30.25 per cent. It will also be assumed that in a tub of butter

CALCULATION OF DIVIDENDS 137

marked 62 pounds, net, there are actually 62.5 pounds of butter
to allow for shrinkage.

Amount of fat credited to patron, 30 per cent of 65 lbs. =19.50 Ibs.

Actual amount of fat in cream, 30.25 per cent of 65.25 lbs. =19.738
Weight of buttermilk, 70 per cent of 65 lbs. =45.5

Per cent of fat in buttermilk, 0.5 per cent

Weight of fat in buttermilk, 0.5 per cent of 45.5 lbs. = .227 |b.
Weight of fat in butter, 19.738— .227 =19.511 lbs.

Weight of butter made, on basis of 80 per cent fat, ax IQ.51I= 24.39

c 62
Weight of butter sold, ane 24.39 =24.2
Ds
24.2—19.
Overrun aE 100 =24.1%
19.5

In the above calculation no account has been taken either of
the mechanical losses or of the fact that the average per cent of
fat in the butter will, of necessity, slightly exceed the minimum
standard of 80 per cent.

In conclusion, then, we would say that while the overrun
may, and will, vary to some extent, from day to day and from
week to week, the creamery that does careful weighing and test-
ing, and credits its patrons with half-pounds of cream and half
per cents of fat, will be likely to have an overrun for the year of
about 23 to 24 percent. If it has this it is doing careful, efficient
work. On the other hand, if the overrun is much above or below
this something is wrong somewhere and needs to be remedied.

Calculation of Dividends.—The method of calculating divi-
dends will vary according to the agreements between the manu-
facturer of the butter and the milk and cream producers. Some
manufacturers agree to make the butter for so many cents per
pound of butter (usually 3 or 4 cents). Occasionally the cream-
ery proprietor agrees to pay a final fixed sum for milk delivered
containing a definite amount of fat (usually 4 per cent). These
two methods are not in use much at the present time, although in
the eastern part of the United States the method of paying the
operator so much per pound of butter-fat manufactured is quite
common.

The two methods most commonly used, especially in the
central West, are as follows:

138 CREAMERY CALCULATION

(1) Pay so much per pound of butter-fat based upon some
standard market price, such as Chicago or New York. The
amount paid now by the central plants for butter-fat is usually
2 or 3 cents per pound below “‘ New York Extras,” and the com-
pany pays all freight or express charges.

(2) Pay per pound of fat based upon the net income of the
creamery.

1. The former method of paying for butter-fat has become
quite common. Nearly all the hand-separator or central plants
are paying for butter according to this method. Payments are
usually made at each delivery or every two weeks. Although
this causes more work, it is much more satisfactory to the patrons
than to pay only at the end of each month.

In order to calculate dividends when paid at the end of two
weeks or at the end of each month, the first step is to find how
many pounds of butter-fat have been delivered by each patron.
If composite samples are taken, and these tested for fat at inter-
vals of one week, which would make about four tests during the
month, and two during half a month, the results of the several
tests may be added, and the sum divided by the number of sam-
ples tested. This may give the average test, but it must be borne
in mind that this method is also likely to give wrong results.
Especially is this so when cream is delivered which varies in
quantity as well as quality during the different parts of the month.

If cream only is being received, it is a good plan to test each
patron’s cream every day, as it is more or less difficult to get
absolutely accurate composite samples from creams of different
richness. Besides this, the patrons can get the test as well as
the weight of the cream of each previous day’s delivery, and thus
know how their account stands from day to day. A little more
labor is involved in doing this, but in the long run it keeps the
patrons better satisfied.

2. If the price of butter-fat per pound is being based upon the
net income, as is the case in nearly all co-operative creameries,

and also in many proprietary creameries, the first step is to find
out how much butter-fat each patron delivered during the spe-
cified time,—two weeks or a month, whichever may be the case.

139 -

CALCULATION OF DIVIDENDS

"yeoq Aq possatfep YI []y “WwoserQ ‘Areueerg Avg soog—- fr ‘org

140 CREAMERY CALCULATION

When this has been obtained, the total pounds of fat delivered by
all the patrons are found. From the gross income the total
expenses of running the creamery are subtracted. The remainder
represents the net income. This is then divided by the total
pounds of fat delivered to the creamery, and the quotient repre- _
sents the price per pound of butter-fat to the patrons.

Knowing the price to be paid to the patrons for 1 pound of fat,
the sum due to each patron is found by multiplying the price per
pound by the total number of pounds of fat each patron delivered
during the specified time.

In some instances provisions are made for a “ sinking fund.”
This is a name given to a fund raised by deducting so much per ~
pound of fat, or per 100 pounds of milk, from each patron’s
delivery at the end of each month. This fund is for the pur-
pose of paying off a debt gradually, or for raising a fund for
new equipment, or other improvements in the creamery. In
case such money is to be withheld, it is deducted previous to
making the final calculation.

Cream-raising Coefficient.—By the term cream-raising coeff-
cient we understand the percentage of the fat removed from the
milk during the process of separation. The calculation of the
cream-raising coefficient may be illustrated as follows:

Suppose we have too pounds of milk containing 4 per cent fat,
and yielding 85 pounds of skim-milk and 15 pounds of cream,
the skim-milk containing .2 per cent fat.

Total fat in whole milk = 100 lbs. X 4 per cent= 4 lbs.
Total fat in skim-milk = 85 lbs. X.2 per cent =.17 lb.
Total fat in cream = 4 lbs.—.17 lb. =3.83 lbs.

3.83 X 100
4
cream raising coefficient.

Statement to Patrons.—A complete statement should be
made at the time of each settlement and should be accompanied
by the check. A statement similar to the following one may
serve as an example:!

=95.75 per cent of the total 4 pounds of fat, or the

1 Creamery Butter-making by Michels.

STATEMENT

OF PATRONS

IN ACCOUNT WITH

Mr.

IScorp (lave) savvy eal Cy

No. pounds milk delivered

ON? NOU are So Me cet i eet ae ia
PAVETAR CATES te os eke ith bok, te \ east ister nts
No. pounds butter-fat . . ........
BricepeDpOUNd) 40. «Whee ates.

Balance due you

Pounds-butter at .

Cans, at
Cash 5
Hauling at....

Total pounds milk delivered a creamery .

Average test at creamery
Total pounds butter-fat at creamery
—— lbs. at

Sales of butter

Less cts. for making.
Balance due patrons

Per cent overrun

Testing witnessed by

Prest.

Secy.

per too lbs

141

CREAMERY COMPANY

ce es

At the end of the year a final statement should be made
by the respective officers, similar to the following one:

REPORT

Commenced Operations........
Aiea antes eye Annual Report, 192....

of the

ANNUAL
Incorporated.............. WOLQoo se
ee
ae Buttermaker:

CAPITAL STOCK, $..........

—_______ CREAMERY COMPANY
, lowa.
Asst. Butter-maker

AT AENG ig) ok ates ake ky ce ees

OFFICERS AND DIRECTORS.

President, ————— Secretary,

Treasurer,

142 CREAMERY CALCULATION

SECRETARY’S REPORT

To the Stockholders: Your Secretary herewith submits the following report
for the year ending December 31, 192....

Total pounds of milk received ‘

Total pounds butter-fat contained in same .

Total pounds butter manufactured

Average test of butter-fat per hundred soundls ei ale
Average yield of butter per hundred pounds of milk
Average price paid per hundred pounds of milk
Average price paid per hundred pounds of butter-fat .
Average per cent increase of churn over test (overrun) . . . . ..........
Average price recelved per POUNdrOn WUELetTI ye) ies nls elem ilci =i Scie aenae
Average monthly expenses of running creamery . . . . . . .......--.
Average cost of manulacturine butter per pound 9.) a. nee

Following is a Monthly Statement for the year 192. .

January .
February .
March
April .
May .
June .
July
August
September
October
November
December

Totals

cs

Ce

TREASURER’S REPORT.

To the Stockholders of the—__________ Creamery Company: Your
Treasurer herewith submits the following report:

STATEMENT OF CASH RECEIVED AND DISBURSED.
RECEIPTS DISBURSEMENTS
Total sine
Respectiullsy aubanitied ID es eo es TEA SUIEC TE
Cashier of Bank.

PAYING FOR FAT IN CREAM 143

STATEMENT OF CASH RECEIVED AND DISBURSED

RECEIPTS. DISBURSEMENTS.

Received for butter . . . §$........ Paid to patronsformilk. . $........
Running expenses of cream-
ery and supplies on hand..........
Paid for machinery, ma-
terial, repairs, etc. (out
of percentage fund) . ..........
Paid dividend on stock for
192..(out of percentage
EUITICL)) ened teen PRR an on ie Se genom tha ath
Paid dividend on stock for
192..(out of percentage

HUUTIGIN Lats week” POMEROY Roth ee ANE Ti
Total amount of cash re- Total amount of orders
ceived and paid to Treas- Ghanian Om Wieser 5 5 econcoose
urer Dice (esse Sues Nala Shee Aeros ame Cash balance in hands of
Cash balance in hands of Treasurer, Jan. 192. . Bee ho) ues
Treasurer, Jan. 192.. Wiel erat
TROLS Cia ean, ne enn a COLA eal cethramas anne A Lcea vi tececah

REPORT OF AUDITING COMMITTEE.

To the Stockholders of the Creamery Company:

We, the undersigned, appointed by your Board of Directors to examine and
audit the Books, Accounts, and Vouchers of the Secretary and Treasurer of the
Creamery Company for the year 192.., hereby certify that we
have carefully examined the same and compared them with the above reports of
said officers, and find them correct.

In witness whereof we have hereunto set our hands at —_______, Iowa
(OK 5 oo oN Olio oo oo oNDEy NO) oq an

\ Auditing Committee.

Paying for Fat in Cream Compared with Paying for Fat in
Milk.—It is evident that when patrons deliver fat in the form
of milk the creamery operator sustains a loss in the skim-milk,
while if the fat is delivered in the form of cream, no fat is lost in
the skim-milk at the creamery, and consequently the cream patron
should receive more per pound of fat delivered than the whole-
milk patron provided the quality of the fat in the cream is 2s
good as that in the form of milk. The butter-maker siou'd
obtain a larger overrun from the fat of the cream than he does
from the fat of the milk. The amount which the patrons should

144 CREAMERY CALCULATION

be paid for fat, delivered in the form of cream, depends upon the
thoroughness of skimming. If rooo pounds of milk testing
4 per cent fat were bought and skimmed, there would be a loss
of about .9 of a pound of fat during the skimming, which would
make about 1 pound of butter, worth about 3o cents. If bought
in the form of cream this loss would not be sustained. The
above loss during skimming, according to the figures mentioned,
would amount to about three-quarters of a cent per pound of
butter manufactured. The fat lost during the skimming process
would amount to about 2 per cent of the total fat. If the cream
fat be increased by 2 per cent, an approximate basis for paying
milk and cream patrons is obtained.

This argument, however, will hold good only when the cream
is graded and paid for on a strictly quality basis. This is decid-
edly the exception, not the rule, at the present time. Milk,
however, is graded to a much larger extent. If it is seriously
off in flavor it is likely to be rejected; furthermore, it has to be
cooled promptly to prevent it from souring, and this holds fer-
mentations in check. Everything considered, we are quite
inclined to the view that the cream and milk patrons of a creamery
should—under present conditions at least—be placed on a par
as to the price paid them per pound of fat.

CHAPTER XI
HEATING MILK PREVIOUS TO SKIMMING

Reasons for Heating.—Owing to the fact that all separators
will skim closer and not clog so easily when milk is heated, nearly
all creameries heat or warm the milk previous to skimming.
When the milk is thus heated and stirred in a pure atmosphere,
many undesirable odors or taints escape. With an increase of
temperature, the viscosity of the milk is lessened, due chiefly to
the softening and separation of the fat-globules. Such an
increased fluidity of the milk lessens the resistant force of the
fat-globules when exposed to the centrifugal force of the sepa-
rator. The higher the temperature the more fluid the milk
becomes, and consequently the more easily the fat can be sep-
arated.

By warming the milk to a high temperature and leaving it for
some time, then cooling quickly again to skimming temperature
(90° F.) and separating, the skimming efficiency of the separator
is increased materially. If the milk has been standing at a very
low temperature for at least three hours, and then is quickly
warmed up to the usual skimming temperature, and skimmed,
the warming of the milk has comparatively little effect in bringing
it into a good condition for skimming. It will thus be seen that
it is possible to skim milk at the same temperature, and yet get
different results, due to previous temperature conditions. Dura-
tion of temperature should be considered as well a: the tempera-
ture itself. .

The temperature to which milk should be heated previous
to skimming varies according to different investigators. The
temperature mostly employed in the past in this country, and
perhaps at the present time, is about 90° F._ This comparatively

145

146 HEATING MILK PREVIOUS TO SKIMMING

low temperature was fixed owing to the supposedly bad effect
high skimming temperatures had upon the body of the finished
butter. Exposing milk at high temperatures to the centrifugal
force in a separator was said to produce a greasy body in butter.
According to experiments conducted at the lowa Experiment
Station by the authors, milk can be skimmed at 175° F. without
any injury to the quality of the butter, providing the cream
is cooled to ripening temperature, or below, as soon as it has
been skimmed. After the ripening has been completed the
cream should be exposed at least three hours to a low tempera-
ture (50° F.) previous to churning.

If the milk is heated in any of the best modern heaters, there
will be no injurious results to the quality of the butter. Pro-
fessor Dean, at the Ontario Agricultural College, has also found
it practical to heat to pasteurization temperature previous to
skimming. In many creameries in Denmark this method of
heating milk is also followed. The Danes, as a rule, however,
pass the heated milk over a cooler before it goes into the sep-
arator.

The chief difficulty encountered by the authors in heating
milk to such a high temperature previous to skimming was
that the upper bearing in the separator got so hot that it was
deemed injurious to the separator, although the bearing did
not heat to such an extent as to cause the running of the machine
to be abnormal in any way.

Advantages of Warming Milk to High Temperature Previous
to Skimming.—The advantages of heating milk to a high tem-
perature (175° F.) previous to skimming may be summarized as
follows:

(x) Undesirable taints are eliminated from the milk to a
greater extent than can be accomplished in any other way,
without applying chemicals.

(2) The heating of whole milk destroys the germs in the
resultant skim-milk and cream practically as efficiently as when
they are heated after the skimming process has been completed.

(3) Less heating and cooling apparatus is necessary.

(4) Closer skimming is possible.

HOW HEATED 147

How Heated.—There are two methods by which milk is
heated previous to skimming. First, by the use of direct live
steam; second, by the use of heaters which heat with steam or
hot water indirectly.

Heating of milk with direct live steam is accomplished in
two ways: first, by entering a steam hose into the vat full of
milk; and, second, by making use of special heaters, which allow
steam to come in direct contact with the milk as the milk passes
through.

The method of heating milk with direct live steam cannot
be too strongly condemned, because it has a bad effect upon
the flavor of the butter. At the Milwaukee National Bucter

Fic. 44.—The Twentieth-century milk-heater.

contest In 1903, where over eight hundred exhibitors were
represented, the authors noticed that where the criticism
“burnt,” “oily flavor”? was made on the score card, the milk
from which the butter was made had in most cases been heated

with live steam. The burnt flavor may possibly be due to the
sudden excessive heat to which the milk will be exposed when
coming in contact with live steam. The greatest danger,
however, in heating milk with live steam is, that impurities
from the pipes and boiler are likely to be transmitted to the
milk, and cause bad flavors. In most of the creameries the
exhaust-steam from the engine is used to heat the water for the
boiler. This steam is likely to carry with it cylinder-oil, which
will impart undesirable flavors to the butter. Some creameries
are also using boiler compounds for the removal of scales. These,

148 HEATING MILK PREVIOUS TO SKIMMING

when subjected to high heat and pressure, are likely to be
transmitted to the steam-pipes, and from there with the steam
into the milk. The scale and rust of steam-pipes are also likely
to be transferred to the milk.

The right way to heat milk previous to skimming is to make
use of one of the special heaters on the market, which heat by
the use of steam or hot water indirectly.

CHAPTER XII
SEPARATION OF CREAM

In the process of the manufacture of butter it is essential
that the fat of the milk shall be concentrated into a compara-
tively small portion of the milk serum. This concentration of
fat carries with it a portion of all the other milk constituents, and
the product is called cream. It is possible to churn milk with-
out any separation,-but-a_much greater loss.is attendant, if the
fat is not brought together by the process called separation.
~The different kinds of cream may be classified according to
the different methods of cream-separating:

Shallow-pan cream.
Gravity cream... | Deep-setting cream.
Water dilution cream (hydraulic).
Cream {
Hand-separator cream.

Centrifugal cream {
Creamery-separator cream.

GRAVITY CREAMING

Shallow-pan System.—This method of creaming is used
mostly on farms which are situated unfavorably in relation to a
creamery, or for some other reasons do not send their milk to
the creamery. It consists in placing the milk in shallow pans,
from 2 to 4 inches in depth, as soon after milking as possible.
The milk is then placed where it can be quickly cooled to a_
temperature of at least 60° F. A lower temperature than this
is desirable if conditions permit. The atmosphere in the room
in which the milk is standing must be pure, free from dust,
draught, and any undesirable taints or odors, since it takes
about thirty-six hours of quiet standing for the cream to rise.
If there is a constant current of air in the room, a leathery

149

150 SEPARATION OF CREAM

cream is likely to form. At the end of this time the cream is
removed by the use of a skimmer, made especially for this pur-
pose. It is difficult, however, to remove all the cream by this
means. The perforated skimmer should never be used. It
allows the thin under-layer of cream to run through and be lost
in the skim-milk.

If the conditions are such that cool water can be constantly
circulated around the pans containing the milk, the temperature
can easily be made to go below 60° F., and the creaming process
is facilitated. When such conditions are present, the depth of the
milk in the pans can safely be increased to about 6 inches. Under
the most favorable conditions about
.5 per cent fat will remain in the skim-
milk.

Deep-setting System.—This system
is undoubtedly the best method of
gravity creaming. When it is properly
carried on the fat can be removed so
completely that no more than .2 per cent
of fat remains in the skim-milk. It con-
sists of putting milk into deep cans
(ordinary four-gallon shotgun cans are
usually employed) immediately after the milk has been drawn
from the cow. Then it is put into cold water, and generally
cooled down to, and maintained at, a temperature of about
55. F. ‘The cream will rise in about twenty-four hours. Better
results can be obtained if the water is cooled down to about 40°
with the use of ice.

One reason why this system is so much in use, even in cream-
ery localities, is that the cream obtained is nearly always of a
good quality. The farmer knows that unless the milk be cooled
quickly, and maintained at a low temperature, the cream will not
rise freely. For this reason the milk is systematically and thor-
oughly cooled, which is one of the great essentials in checking the
growth of the ferments in milk and keeping the milk in good con-
dition. In many parts of the eastern United States, the deep-
cetting system is in general use. A special form of can is used,

Fic. 45.—Cooley creamer
and elevator.

GRAVITY CREAMING 151

it is simply an ordinary four-gallon can, about 8 inches in diameter
and 20 inches deep. It hasa glass on one side near the bottom or
near the top, which allows the reading of the thickness of the
layer of cream. On each side of the glass is a graduated scale,
which gives the reading in inches. In case the cream is being
sold to a creamery, the hauler comes along, notes the depth of the
layer of cream, and records the number of inches of cream oppo-
site the patron’s name. At the end of the month, or whenever
the time for payment comes, the money is apportioned according
to the number of inches of cream delivered by each of the patrons.
No test for fat is made. This is what is known as the “‘ Cooley
system,” and is used quite extensively in the East, especially in
Massachusetts.

While cream usually arrives at the creamery in a fair condition,
there is the objection that the cream is always thin. It seldom
contains any more than 18 or 20 per cent of fat.

No good explanation has yet been given why cream in a deep
layer of milk at 40° F. should rise more quickly and more com-
pletely than in a thin layer at a higher temperature. Arnold !
seeks to explain it by saying: “‘ Water is a better conductor of
heat than fat; hence when the temperature of the milk varies
either up or down, the water in the milk feels the effect of the
heat or cold sooner than the fat in the cream does. Therefore
the cream is always a little behind the water in swelling with heat
or shrinking with cold, thus diminishing the difference between

the specific gravity of the milk and cream when the temperature
is rising, and increasing it when the temperature is falling.”’

This explanation is, according to Babcock,” not satisfactory.
He says: ‘“ Though it is true that water is a better conductor
of heat than fat, the small size of the fat-globules renders it
impossible that under any circumstances there can be more than a
small fraction of a degree of difference between the temperature
of the fat and that of the milk serum. Moreover, with the limits
of temperature practical for a creamery, (go° to 40° F.), the
coefficient of expansion of butter-fat is more than three times as

1 American Dairying, p. 210.
? Wisconsin Experiment Station, Bull. 18, p. 24.

152 SEPARATION OF CREAM

great as that of water, so that in order to maintain the same rela-
tive difference in their specific gravities when the temperature is
falling, the milk serum must cool nearly three times as quickly
as the fat. In other words, when the milk serum has cooled from
go° to 40°, or 50° F., the fat-globules should have lost less than
17°, and should still have a temperature of over 70° F., a differ-
ence between the temperature of milk serum and fat of more
than 33°. Such a condition is manifestly impossible, but
a less difference than this would cause the fat to become
relatively heavier than at first, and would operate against the
creaming.”

A low temperature increases the viscosity of the milk, and
consequently it would seem that the resistant force of the fat-
globules in their upward passage through the milk serum would
be increased, and thus retard the creaming. Babcock maintains
that fibrin is partially precipitated when milk is allowed to stand
at a medium high temperature. The fibrin, when precipitated,
forms a fine network of threads permeating the milk in all direc-
tions, similar to the network of fibrin in coagulated blood. It is
possible to conceive that such a network would interfere with the
rising of the fat-globules, at comparatively high temperatures.
The reason that fat-globules will rise more quickly and more
completely in the deep-setting system than in the shallow-pan
system, might be explained on this fibrin theory were it not for the
fact that experiments conducted at the Cornell Experiment
Station show that the setting and cooling of milk may be delayed
long enough for this fibrin to form, without any effect upon the
separation when set and cooled.

Probable Explanation.—There are two factors which, taken
in conjunction with each other, seem to offer a reasonable
explanation of the efficiency of the deep-setting system.

The first of these is that cooling the milk to, and holding
it at, a low temperature keeps the milk serum in a much better
physical condition. It may not be so fluid as it would be at a
higher temperature, but there is a minimum formation of fine
masses or particles of curdy matter that would either imprison
some of the fat or offer obstruction to the fat-globules, and

_ GRAVITY CREAMING 153

clusters of globules, in rising. It is a fair assumption that in the
experiment at the Cornell Station the milk was not held long
enough, before cooling, seriously to impair its physical condi-
tion.

The second very probable factor is that of the formation of
fat clusters, through large fat-globules rising faster and coming
into contact with smaller ones. ‘These and other clusters would
continue to pick up isolated globules and smaller clusters, and so
the process would continue; clusters would, of course, rise more
readily than individual globules, and larger clusters would rise
more rapidly than smaller ones. The result would be that,
owing to the good physical condition of the milk—the absence
of casein particles to enmesh the fat-globules and offer obstruc-
tion—practically all the fat-globules would find their way to the
top.

Water-dilution Cream (Hydraulic.)—It was thought, at one
time, that a modification of the deep-setting system, through
the dilution of the milk with water to the extent of 25 per cent to
50 per cent, would greatly add to its efficiency, through reducing
the viscosity of the milk. The idea was, of course, commercial-
ized and a number of so-called “ dilution cream separators ”’
were placed on the market. The method is still practiced
to some extent, but it is by no means as general as it was at one
time. |

While it is true that under very exceptional conditions—such
as in setting the milk of an occasional individual cow near the
end of her lactation period—some advantage may be gained, the
principle has no general application. It must be remembered
that, while the addition of water to milk makes it more liquid, it
also reduces the difference in specific gravity between the milk
serum and the butter-fat, and it is upon this difference that we
depend to bring about a separation.

Even though the skim-milk should, at times, show a lower
per cent of fat, this is only an apparent advantage, as there is a
much greater quantity of it. Wing! obtained the followin
results with diluted and undiluted milk: i

1 Milk and Its Products, p. 105.

154 SEPARATION OF CREAM

Diluted with 25 per cent water, set at 60° F. (39 trials), 0.77
per cent fat in the skim-milk.

Undiluted, set at 60° F. (30 trials), 1.00 per cent fat in the
skim milk.

Undiluted, set at 40° F. (30 trials), .29 per cent fat in the
skim-milk.

A test of .77 per cent, where the milk is diluted to the extent
of 25 per cent, means a greater loss of fat than where the skim-
milk from undiluted milk tests 1.00 per cent.

It will be noted that, in his trials under the dilution method,
Wing set the milk at 60°. The reason for this was that advocates
of the system contended that it would bring about such a speedy,
and yet complete, separation that it was unnecessary to adopt
low temperatures. Wing’s experiments prove two things;
first, that whether milk is diluted or undiluted the loss of fat is
heavy if the setting temperature is high, and, second, that where
the milk, without dilution, is set at a low temperature the cream-
ing coefficient is quite satisfactory.

The valid objections to the dilution method are as follows:

Much more bulk to handle, the use of a larger number of cans,
and increased labor.

Danger of contamination of the milk and cream through the
use of impure water.

Impairment of the value of the skim-milk for feeding.

Injury to the cream or butter—the product has an unde-
sirable, flattish flavor.

The loss of fat in the skim-milk is too great, as the experiments
by Wing show.

CENTRIFUGAL CREAMING

In the separation of cream by centrifugal machines, the
same principle is used as in the gravity system of separation.
The only difference is that in the centrifugal method the force
which separates the cream from the milk is generated by artificial
methods, and acts in a horizontal direction;. in the gravity system
the force which separates the cream from the milk is only that
which results from the difference in the specific gravity of the

CENTRIFUGAL CREAMING 155

cream and the skim-milk, and the force acts in a vertical direc-
tion. The force generated in the separator is several thousand
times greater than the natural force in the gravity method.
For this reason the cream separates almost instantaneously after
the milk has entered the separator and is exposed to the cen-
trifugal force.

Advantages.—The centrifugal separator has several advan-
tages over the gravity method, which are apparent without
detailed elaboration. In the first place, the range of tempera-
ture and condition of the milk at which the cream can be suc-
cessfully separated is much greater than that for successful
separation by the gravity method. Second, a much better
quality of cream can be obtained by the centrifugal system,
as the separation can be done before the milk gets old, while
by the gravity method the time required for efficient separation
is so long that the cream deteriorates more or less before it is
removed from the milk. Third, by the centrifugal method the
thickness of the cream can be regulated to suit requirements,
while by the gravity method the thickest cream that can be
obtained is about 20 percent. Fourth, by the centrifugal method
many impurities and undesirable germs are removed, while in
the gravity method the exposure to open air, more or less impure.
is likely to contaminate the milk with taints, and also allows the
germs to fall into it. Fifth, by the centrifugal method the skim-
milk is left in a more natural condition. The milk can be
skimmed soon after milking, or after it has been delivered to the
- creamery, and thus be in the best possible condition for feeding
purposes. Sixth, the centrifugal method permits of a more
thorough separation of the fat. Butter-fat, as a rule, is too
expensive to feed, when good and much cheaper substitutes can
be had.

History of Centrifugal Separators.—The first centrifugal
separator was a very simple one. It consisted of buckets hanging
on the ends of arms, or on the periphery of a rotating horizontal
flat wheel which swung on a central axis. The milk was placed
in the buckets and whirled for a time, and then the machine (if
we may call it such) was stopped, and the cream removed in the

156 SEPARATION OF CREAM

same way as in the gravity system. This method of separation,
according to J. H. Monrad,! had its origin in 1864. As early as
1859 Professor Fuchs of Carlsruhe, Germany, suggested testing
the richness of milk by swinging tubes holding the samples of
milk. In 1864 Prandtl, a brewer of Munich, separated milk by
such a device. In 1870 Rev. F. H. Bond, of Northport, Massa-
chusetts, worked out a method of separation which consisted of
two small glass jars attached to a spindle making 200 revolutions
per minute. By one hour’s whirling the cream was brought to
the top.

In 1875 Prandtl exhibited at Frankfort-on-the-Main a con-

A

Tiss cl

Ne: YA SUE _

/7, i] ) \ e| (
= { f
\\ WS FA) 4 a =

Fic. 46.—First centrifugal separator. (From Dairy Messenger.)

tinuous separator, which did not at the time attract much atten-
tion, due chiefly to the excessive amount of power needed to
overcome the resistant force of the air. In 1876 a Danish engi-
neer named Winstrup succeeded in improving the old bucket
method. In 1877 Lefeldt and Lentch offered for sale four con-
tinuous separators with different capacities (from 110 to 600
pounds of milk per hour). During that year also, the first
practical centrifugal creamery was established at Kiel, Germany.
In 1877 Houston and Thompson of Philadelphia filed a patent for
the continuous method of separation of cream from milk. The
patent was allowed in 1891. In March, 1877, Lefeldt and Lentch
1 Dairy Messenger, Oct., 1892, p. 109.

CENTRIFUGAL CREAMING 157

invented a separator similar in construction to the hollow bowl—
a more recent type. ‘This machine did not revolve at so rapid a
rate as our modern machines do, nor did it have arrangements for
continuous inflow and discharge. It was intermittent in its
work, and it was necessary to stop at intervals to remove the
cream and skim-milk. The year 1879 marked the greatest
advancement toward the perfection of modern separators, in the
appearance of the Danish Weston, invented in Denmark, and
the De Laval, invented in Sweden during that year. This led
to continuous milk and cream discharges, and consequently also
to the continuous inflow of whole milk. These machines were
of the hollow-bowl construction.

Modern Separators.—Since the year when the Danish Weston
and the De Laval machines were invented, many different
types of separators with different contrivances within the bowl
have been put upon the market. Baron Bechtelsheim, of
Munich, is given the credit of having discovered that certain
contrivances on the inside of the machine increase the efficiency
and capacity for skimming. This discovery was made, accord-
ing to J. H. Monrad,! in 1890. This invention was bought by
the De Laval Company.

The principal part of practically all the separators is a bow]
rotating in a vertical position, with or without contrivances
inside the bowl. Machines having a bowl rotating in a horizontal
position are, so far as the authors know, not in use at the present
time. Such a machine was once manufactured at Hamburg,
Germany, and was called ‘“ Peterson’s Centrifugal Machine.”
Another German machine, called “‘ The Page,” was also manu-
factured in the horizontal bowl style.

From the above it will be noticed that four separate steps
are recognizable in the evolution and improvement of separators:

1. Revolving Bucket Centrifuge;

2. Intermittent Hollow Bowl;

3. Continuous Hollow Bow];

4. Continuous Separator with contrivances within the Bowl.

The science and practice of separation of milk and cream have

1 Dairy Messenger, Jan., 1892, pD. 9.

158 SEPARATION OF CREAM

seemingly reached a high state of efficiency. It seems almost
improbable, considering the many new improved separators on
the market, that any other great improvement could be made
which would add a separate stage to the improvement of our best
centrifugal milk separators of to-day.

Classification of Separators.—Owing to the many different
standard types of separators
now on the market, it is im-
possible to describe each one
in detail. For this reason the
classification appearing below
has been made. There are
undoubtedly many other
types, especially in foreign
countries, with which the
writers are not familiar, and
which are not mentioned
here. The following classi-
fication will, in some meas-
ure, illustrate the different
makes of separators on the
market to-day:

Many of these separators
which cause the milk to pass
up and down in vertical sheets have the bow] contrivances corru-
gated and perforated with holes so that the skim-milk and cream
also assume a partly horizontal direction.

Process of Separation.—From the illustrations, the structure
of the more common types of separator bowls is readily under-
stood. The whole milk may be made to enter at the bottom or
top of the bowl when revolving. In the Sharples, it enters at the
bottom, the more common way is to have it enter at the top.
As the milk enters the bow] and is exposed to the centrifugal force,
it immediately begins to separate into three distinct layers. The
centrifugal force acting in a horizontal direction forces the
heaviest portions of the milk and the precipitated albuminoids,
ash, filth, and a multitude of germs over next to the wall of the

Fic. 47.—The Simplex separator.

CENTRIFUGAL CREAMING 159

Hollow bowl... { De Laval (old style).
Sharples.
Omega
Cause milk to | Empire.

pass in thin | Davis.

Farm sep- sheets verti- | United States.
arators. cally in bowl | National.
Reid.
Contrivances Dany Qisen:
as De Laval.
in bowl.

Cause milk to | Peerless.
separate into | Swea.
almost hori- }/ Westphalia
zontal thin (Cleveland)
sheets. Towa.
Internat. Cream
_ Harvester.

Separators

Improved Danish Weston (Reid.)
Hollow bowl | Sharples (old style).
De Laval (old style).

Creamery Cause milk to | United States.
power : : .
Sc pass in thin | Simplex.
aa sheets verti- | Sharples (new

cally in bowl. style).
Contrivances in
bowl. ~ Cause milk to

separate inal- | De Laval.

most horizon- | Springer.

tal sheets.
separator bowl, and into a solid and more or less gelatinous layer,
which is known as the “ separator slime.” In very impure milk
this substance is so plentiful that it is likely to clog the separator
in a very short time, and before much separation is accomplished
it is necessary to clean out the bowl. The second layer is the
skim-milk, while the cream, being the lightest, is forced to the
center of the bowl and forms the third portion mentioned. There
is no distinct line of demarcation between the layers of skim-milk
and cream.. They overlap each other and form a sort of zone,
rather than a sharp separation. The richest cream is nearest the
center of the bowl, and gets thinner toward the outer portion of
the bowl; consequently, by turning the outlet for the cream, or

160 SEPARATION OF CREAM

cream screw, nearer the center of the bowl, the cream is increased
in richness. Turning it away
from the center causes the cream
to be thinner. The skim-milk
that is forced clear to the cir-
cumference of the bowl contains
the least fat, and consequently
the skim-milk is always first
removed from this portion of
the bowl. Usually the skim-
milk outlet is brought in towards
the center of the bowl at one end
through tubes extending from
the circumference of the bowl.
If this were not done, some diffi-
culty would be involved in arranging a receiving-pan for the dis-
charged skim-milk. If the skim-milk were discharged near the
circumference of the bowl, it would come out with a heavy force.

=i

el Las

ny
(J

Imi

util

Fic. 49.—Showing “ butter extractor” Fic. 50.—Showing cross-section of
attached to De Laval separator. The De Laval separator bowl.
butter extractor is not known to be
in use now.

CONDITIONS AFFECTING EFFICIENCY OF SEPARATORS 161

Also, if the outlet for the skim-milk were near the circumference
of the bowl a great deal more power would be required to run
the machine. As the skim-milk passes through the tubes
towards the center it gives up its force. The nearer the skim-
milk outlet can be brought to the center of the bowl, the more
easily will the machine run.

The size of the skim-milk outlet is usually such that it bears a
certain relation to the size of inlet, size of bowl, and speed of the
machine. Most skim-milk outlets are made so as to discharge
from .4 to about .g or a little more, of the whole milk that enters
the bowl. The remainder is the cream, which is forced to the
center of the bow! and discharged through the cream outlet.

CONDITIONS AFFECTING EFFICIENCY OF SEPARATORS

1. Manner of Heating Milk.—Owing to the fact that fat-
globules rapidly change their shape and properties when exposed
to heat and excessive agitation, it is essential that care
should be taken in heating milk previous to skimming. When
fat-globules are heated they become more liquid, and if stirred
very much the clusters of fat-globules break up more rapidly.
The individual globules, if stirred violently, will break or sub-
divide into several small ones. The higher the temperature
of the milk, the more fluid it becomes, and the easier the separa-
tion. If milk is stirred violently, the individual fat-globules
break up into smaller ones, which are separated from milk with
difficulty. The table! on p. 162 illustrates what effect the dif-
ferent degrees of agitation of milk have upon the efficiency of
separation.

In the experiments the diameter of the agitator in the pas-
teurizer was 14 inches. The speed at the periphery, at 250
revolutions per minute, was 15 feet per second.

It will be seen from the table (p. 162) that the higher the speed
of the agitator, the greater the difficulty in getting a complete
separation. Besides the speed of the agitator in the heating
apparatus, undoubtedly the shape of the pasteurizer is a factor

1 Hoard’s Dairyman, Fort Atkinson, Wis.

162 SEPARATION OF CRISAM

Av. Mat

No of Per Cent

Iixperi- | in Skim-
ments mill
Mille heated! in vat, Mot pumped vi iciciec asserts ee nest 10 aly)
Milk heated in pasteurizer, 200 rev, of agitator per min, . 8 .115
Milk heated in pasteurizer, ago rey, of agitator per min, . 3 2118
Milk heated in pasteurizer, 300 rev, of agitator per min, . 8 134.
Milk heated in pasteurizer, 350 rev, of agitator per min. . 2 143
Milk heated in pasteurizer, 4oo rev, of agitator per min, . y .108
Milk heated in pasteurizer, 500 rey. of agitator per min. . 4 1225
Milk pumped by the turbine pump at ra2" Pew... een. 3 . 129
Milk pumped by the turbine pump at 04° Poe c cece ees 3 110
Milk pumped with the pump, effective at 192°. .......6. 3 117
Milk pumped with the pump, effective at 64°. .......65 3 11S

in determining the efficiency of the subsequent separation, For
instance, the milk in most horizontal pasteurizers is, even at low
speed, exposed to considerable agitation.

If the milk is suddenly heated from a low temperature to
about 80° or 00° F. and then skimmed, the heating does not
facilitate the skimming process very much, It is essential that
the milk be exposed to this temperature for a considerable time.
The fat-globules do not warm as rapidly as the milk serum. ‘This
diminishes the difference between the specific gravity of the two
substances, consequently completeness of separation becomes
more difficult, If milk is heated to a high temperature, say, for
instance, 170° F., the separation will be sufficiently complete
without exposing the milk for any length of time to that temper-
ature,

Machines are now made, and are on the market, which will
bring the milk into such a condition that the fat-globules cannot
be separated from it. ‘The process is called “ homogenization.”
[t consists of bringing the milk under certain pressure, and then
forcing it out through a special valve. ‘This relief, through this
special valve, breaks up the existing fat-globules into very
minute ones, which cannot be separated from the milk by
gravity mehtods, and which it is impossible to separate come
pletely by centrifugal methods. Homogenization of milk is

CONDITIONS AFFECTING EFFICIENCY OF SEPARATORS 163

carried on to some extent in Europe. The process practically
insures uniform quality to the milk patrons in the distribution
of milk in cities, and secures a more uniform consistency of the
product.

2. Condition of the Milk.—In order to get complete separa-
tion, and keep the separator in good running order, it is essential
that the milk should be in as good physical condition as possible.
Coagulated, slimy, or otherwise viscous milk separates with
difficulty. When such milk is on hand it should not be mixed
with the milk that is in good condition, as it might tend to coag-
ulate more of the good milk, and the coagulated or slimy lumps
are likely to clog the separator. Such milk should be left until
all the good milk has been separated. Then, if the coagulated
or slimy milk is thoroughly stirred so as to reduce its lumpiness,
it may be run through the separator successfully. It is a good
plan not to feed the separator quite so heavily when this quality
of milk is being run through. If the inlet is partly shut off, it will
usually run through without clogging. Milk containing impuri-
ties in suspension should be thoroughly strained previous to
separation.

Overfeeding the Separator.—When a separator is being over-
fed with milk there is a tendency for the machine to do less com-
plete work. This is due to the fact that the more milk is being
fed into the separator the less time it will be subjected to the
centrifugal force. It is possible to underfeed the separator as
well. As has been mentioned before, the inlet can be closed to
such an extent as to cause nearly all the discharge to take place
through the skim-milk tube.

As a rule when the machine has been set so as to allow the
milk to flow in at a certain rate, it will continue to admit prac-
tically the same amount of milk all through the skimming period.
Among the conditions which may alter the rate of inflow to some
extent, are the amount of heat and the change of pressure, due to
different amounts of milk in the receiving-vat. Temperature
will slightly affect the rate of inflow. The higher the tempera-
ture, all other conditions being the same, the more milk will pass
through the inlet.

164 SEPARATION OF CREAM

3. Speed.—All modern machines have a device by which their
speed can be determined. Most speed indicators consist of a
little wheel, which, when pushed up against the spindle of the
separator while running. turns around and permits the calcu-
lation of the speed of the separator. If the wheel on the speed-
indicator makes to revolutions during ten seconds, the machine
turns 1000 times during the same time. During one minute the
separator will run six times as many revolutions, or 6000, as ten
seconds is one-sixth of a minute. Most speed-indicators are so
adjusted as to turn one revolution for every roo revolutions of the
machine. The higher the speed, the more thorough is the sepa-
ration. Nearly all machines are balanced to do the best work at a
certain definite speed, varying with different machines, and
indicated in the directions for operating. It is essential that the
machine should be brought up to speed gradually, and no milk be
allowed to flow through it until after it has acquired its full speed.

During the run, all machines are likely to vary more or less
in speed, owing to different causes. Pulleys are likely to slip
on the shaft, and belts are likely to become loose, and thus
cause variations in the speed. ‘The steam pressure may get low,
and cause all of the machinery in the creamery to run more
slowly. This cause, however, is not a very common one where
belt separators are used. If the engine has an automatic gov-
ernor on it, the speed is usually quite uniform. Where steam-
turbine machines are used, the speed of the machine is more likely
to vary with the different amounts of steam pressure on the
boiler. With turbine separators it is very essential to keep an
even steam pressure. Some turbine separators have a safety-
valve attached to prevent too high speed.

The reason why the prevention of a variation in speed is so
essential is that a slight variation in the speed has a compara-
tively large effect upon reducing or increasing the centrifugal
force. The centrifugal force generated in a machine varies
according to the diameter of the bowl, and according to the
speed of the machine. The greater the diameter of the bowl,
the less speed or velocity is required in order to get a certain
force. The centrifugal force varies in direct proportion to the

CONDITIONS AFFECTING EFFICIENCY OF SEPARATORS 165

diameter of the bowl; that is, if the diameter of the bowl be
doubled, then at the same speed, the centrifugal force has been
doubled. The centrifugal force varies in quadratic proportion
to the speed of the machine; that is, if the speed of the separator
is doubled, the centrifuga] force is increased four times. From
this it will be seen that speed is a great factor in determining the
centrifugal force generated. It is not a good plan to have the
diameter of the bowl too large, for the following reasons: A large
bowl is more likely to be thrown out of balance; it is harder to
keep on the bearings; and it is heavier and more unhandy to
handle. For these reasons it is better to lessen the diameter of
the bowl and increase the speed. ‘This, of course, is true only to a
certain limit.

Steadiness in Running.—Smooth running of a separator is
one of the first essentials. If a machine runs roughly, there will
not be good separation, and it is dangerous to run it. The
bowl itself is likely to jump out, or burst. The causes for
unsteadiness in running are many. It may be due to a bent or
sprung spindle; the machine not standing level; changing covers
to bowls; using clamps which do not fit the bowl cover; unclean,
worn-out bearings; condition of the bowl, and contrivances
inside the bowl; and dented and rusty bowls. Occasionally it
happens that a machine is run backwards. This is likely to
cause the cover of the bow] to run off.

Thickness of Cream.—The efficiency of skimming depends
to some extent upon the thickness of the cream skimmed. Most
separators, however, will skim within quite a wide range as to
thickness. The richness of cream usually skimmed by separators
ranges from 25 per cent to 50 per cent. Most separators, how-
ever, will do good skimming even if the cream contains as high
as 60 per cent fat. This, however, should be considered to be
about the maximum, in order to get the best results from a sep-
arator.

Slush in Bowl.—As has been mentioned before, there is
always a thick, slimy substance which adheres to the bowl-wall.
The composition of separator-slime is, according to Fleischmann,
as follows:

166 SEPARATION OF CREAM

Water si aR tin) see ee pe ee 67.3
Fatiysvc Qi Sayer! seh. 2b Ena eee eee ene ees Lea
Caséousimatter: 2) ae eth: te eee ee 25.9
Other cxeanicisubstancess); Sess eee 21
NSH, MRL SE es SE a eet es eae ee 3.6

100.0

At the center of the bowl, or along the perpendicular axis,
there is always considerable cream. It is practically impossible
to get all the cream out of the bowl, even if it is flushed with
much water. The amount of slush varies somewhat with the
different kinds of separators, and it is essential that this amount
should be taken into consideration when the comparative
skimming efficiency of different separators is considered. When
the test extends over a comparatively long period, and the milk
skimmed amounts to several thousand pounds, the bowl slush
does not greatly affect the conditions for comparative results;
but when the test is short, and only a hundred pounds of milk, or
thereabout, is skimmed, the amount of fat left in the bowl-slush
will have considerable influence upon the choice of a machine.

General Remarks.—In order to keep the separator in good
running order, it must receive care. The belt should neither be
too tight, nor too loose. If too tight it is likely to bind, heat,
and set the bearings of the separator. If too loose it is likely
to slip, and to wear out more quickly. The machine should be
well oiled. It is better to use a trifle too much oil than not
enough. If a bearing is once heated, the machine will never
run as well again. !

The bowl should be handled with great care. Bowls, or
parts belonging to the bowl, can be kept from rusting by boiling
them in water, or by steaming them thoroughly after they
have been cleaned. If scalding-hot water is used before the milky
portion has been washed off, the albuminoids will be scalded on
to such a degree that it will be difficult to get them off. This
applies to all dairy and creamery utensils. It is said that tin
or ironware may be prevented from rusting by being dipped into

CONDITIONS AFFECTING EFFICIENCY OF SEPARATORS 167

hot water after washing. If the bowl, pail, or whatever utensil
it may be, is turned over to drain after being dipped in hot water,
the heat taken up by the utensil will in a short time perfectly
dry the apparatus. If the bowl is steamed, it should be heated
thoroughly to make it dry quickly.

If the milk supply gets short during the run, and it is necessary
to run the machine without feeding milk, the machine should
always be flushed with lukewarm water. This will, in a measure,
prevent clogging. Scalding-hot water should never be used for
flushing the separator. The cream and skim-milk tubes should
be carefully cleaned, with the special wire provided for that pur-
pose, each time the machine is washed. ‘The contrivances on the
inside of the bow! should also be handled with care so as not to
injure them in any way. ‘They should be treated with hot water,
as mentioned above, in order to keep them from rusting.

When the bowl is not to be used for some time, it should be
oiled well to prevent it from rusting. It is easier to oil.a sepa-
rator bowl than it is to scour the rust off later on.

CHAPTER Xdih
FARM SEPARATORS

THE factors which influence the richness of cream are dealt
with in Part II of the chapter on “ Variation of Fat in Milk and
Cream,” while those affecting the efficiency of skimming are
dealt with in the chapter on “Separation of Cream.” These
factors apply equally to power and farm separators. The con-
ditions under which farm separators are operated warrant this
separate chapter upon this subject.

Introduction of Farm Separators.—Small, or hand, separators
have been manufactured for a great many years, but their
general adoption is of comparatively recent date. For instance,
it was in 1894—not so very long ago—that hand separators
were introduced into the large dairy state of lowa. ‘Thirty years
ago practically all of our creameries were milk-receiving cream-
eries, while to-day the great bulk of our creamery butter is made
from cream separated on the farm by means of hand or farm
separators. Naturally the people of the Central West (Iowa,
Kansas, Nebraska, Missouri, Minnesota, Illinois and Indiana)
have been foremost in the development of this system, as it is
best suited to their conditions. It permits many of the farmers
who engage in dairying in a comparatively small way to become
patrons of creameries located at considerable distances from
them.

Reasons for Introducing Farm Separators.—It requires an
investment of about $100 to purchase a hand separator; it may
therefore be concluded that some good reasons lead farmers to
make such an investment. The chief of these may be briefly
stated as follows:

(1) The farmer is able to skim the milk immediately after it
has been drawn, thereby enabling him to feed the milk while

168

REASONS FOR INTRODUCING FARM SEPARATORS 169

it is In a warm, sweet, unadulterated condition. If he hauled
the milk to the creamery, the skim-milk would be likely to come
back in a sour and curdled condition, and at times watery. (Ina
well-conducted creamery these latter conditions do not exist.)

(2) The high cost of hauling in many instances makes it

Fic. 51.—The Omega hand separator.

almost impossible to get the milk to the creamery. Even if
the roads are good, the distance to the creamery is frequently
so great that it is impossible to get haulers, nor is it practicable
for every farmer to haul his own milk every day. Especially
is this so during the busy season of the year. In the fall, when

170 FARM SEPARATORS

milk is scarce, it is almost impossible for the hauler to get enough
milk to make it profitable. In many cases it is necessary to pay
an excessive price for hauling milk.

When cream routes are established instead of milk routes,
one hauler can usually cover as much territory as three could
under the milk system. ‘Two thousand pounds of milk, testing
4 per cent and containing 80 pounds of fat, would represent

we approximately a load of milk. At 25
cents per too pounds, this would mean
a cost of $5.co for getting that much
milk hauled. If the same amount of
butter-fat were hauled in the form of
cream, it could be gathered for about
3 cents per pound of fat, or the cost
of hauling in this particular case would
be $2.40. Under the milk system it
would be necessary to haul the milk
to the creamery every day, while under
the cream system it is usually gathered
every other day in the summer, and
every three days in the winter. It is
usually considered that there is a saving
| of about 2 to 3 cents per pound of

OF butter-fat in hauling, by making use

Fic. 52.—The De Laval hand of the cream system instead of the

separator. (Balty NO.) ial system. This, of course, would
vary according to local conditions.

3. The use of hand-separators makes farmers more inde-
pendent than they are under the whole-milk system. They
are not compelled to support their local creamery unless they
deem it advisable. They can ship their cream to any place that
they may choose. If the butter from the hand-separator cream
is to be of as good quality as that made by the whole-milk system,
the cream should be delivered as often as possible. Every day is
preferable to every other day. In case frequent delivery is made,
it becomes quite essential for the farmer to patronize the local
creamery, as very few farmers keep sufficient cows to get enough

OBJECTIONS TO FARM SEPARATORS 171

cream to pay them to ship by rail every day. Usually it does
not cost much more to ship a can full of cream than it does to
ship it half or three-quarters full.

Objections to Farm Separators.—Under the present system

Fic. 53.—Simplex hand separator and the different parts of bowl.

of shipping cream long distances the quality of the butter made
from it is often of a lower grade than that made from good whole
milk. This is not due to any fault of the system, but to the poor
care which the separator and cream may receive. The separator
on the farm is sometimes kept in an unsuitable place, often in the

172 FARM SEPARATORS

barn. If the milk is separated in such a place it will absorb odors
and undesirable taints. The cream is not always taken care of
properly after it is separated. The separators may not be
cleaned well. A separator cannot be kept in good condition by
simply flushing out the bowl with cold water at the end of each
separation. It must be taken apart at the close of each skimming,
and all the parts must be washed thoroughly in Jukewarm water,
and then scalded. The time and power required to skim the

Fic. 54.—Sharples separator and parts of bowl.

milk and to care for the cream are in many instances regarded as
objections to the system.

Thickness of Cream.—Most butter-makers at central plants
prefer cream containing about 30 to 4o per cent of fat. Such
cream is not thick enough to cause any inconvenience in sampling
and weighing. It can be diluted with a good starter and ripened
without becoming so thin as to produce unfavorable conditions
for churning. By some it is deemed advisable to skim even
thicker than this, up to 0 per cent. Cream containing this much
fat, however, is difficult to handle, especially during cold weather.
It becomes so stiff that it is difficult to pour, and there is also

THICKNESS OF CREAM 173

danger of losing more or less cream through its adhering to the
sides of the cans.
A thick cream is advisable from the farmer’s standpoint.

Fic. 56.—Agos hand tester.

The thicker the cream is, the more skim-milk he will retain on
the farm for feeding purposes. It can also readily be seen
that if thin cream is skimmed greater can capacity is necessary,

174 FARM SEPARATORS

and the express charges will be heavier than if the thicker cream
were skimmed. Rich cream does not sour so rapidly as does thin
cream.

The richness of cream can be readily ascertained by the use of
a Babcock test, which every farmer should have in his possession.
A whole outfit for testing fat in cream or milk can be had for
about $10.00 from any creamery supply-house. By the use of
such a test, the farmer can test his cream and skim-milk. He
can also test the milk of each individual cow in the herd, thereby
ascertaining which ones are profitable. By the use of such a test
on the farm, the farmer can test his cream daily, and compare

Fic. 57.—Tread-power attached to United States hand separator.

results with those from the creamery, thereby enabling him to
detect any mistake which may happen at the creamery.

Power for Farm Separators.—Hand-power is often men-
tioned as an objection to farm separators. When a considerable
quantity of milk is to be skimmed, it is certainly hard work to
skim with hand-power. Windmills could not well be used as
they do not give uniform speed. ‘Tread-power is often used to
run farm separators and is very well adapted to this purpose, as it
is steady and uniform, and does not cost anything after the
apparatus has once been purchased. ‘The power can be supplied
by using different kinds of animals: Sheep, goats, dogs, and

POWER FOR FARM SEPARATORS 175

20 % 25% 30 % 40 %

Fic. 58.—Showing the height to which cream free from air bubbles must be raised
in a pipette to get 18 grams of cream. It shows that to measure cream in a
pipette is inaccurate in cream testing. (Iowa State Dairy Com. Report, 1903.)

176 FARM SEPARATORS

bulls are used for this purpose. The process does not usually
last very long, and the work is not considered heavy. Steam is
good power, but it is hardly ever obtainable on the farm.
Small gasoline-engines are also used very successfully.

The machine should always run smoothly in order to get
efficient skimming. It should never be stopped and started with
a jerk. If it is started slowly there will be less danger of breaking
any of the gearing parts. The bowl and inside parts should be
kept from rusting as described previously on page 167. The
bearings should be well oiled. It is a good plan to have an extra
bearing or two on hand, so that if one happens to wear out
another one can be put in. The bearings should be cleaned at

Progeny of a
single germ in ©
twelve hours

Fic. 59.—Showing the effect of cooling milk on the growth of bacteria. The bene-
ficial results of early chilling are readily apparent. (From Bul. 62, Wis.)

intervals. When kerosene is occasionally used on the bearings
they do not need to be cleaned so often, because it keeps them
from gumming. The machine should be turned at the proper
speed, as indicated in the directions. A thicker cream will
result from rapid turning; consequently more skim-milk will be
obtained. Slow turning causes inefficient skimming and thinner
cream.

Care of Cream on the Farm.—The first step in the production
of good cream is clean milking. This:can be accomplished only
when barn, cows, and utensils are clean. It is a good plan to
dampen a cloth, and wipe off the cow’s udder and sides previous
to each milking. The milker should never wet his hands while

CARE OF CREAM ON THE FARM Wie

milking. Dust should not be stirred up in the barn during
milking, as the dust particles carry with them a large number of

Fic. 60.—The condition of the cow shown in this cut is favorable for the accumu-
lation of loose dirt. (Bul. 84, Ill.)

undesirable germs, and when these settle in milk they are likely
to produce taints. If cloth strainers are used they should be kept

178 FARM SEPARATORS

scrupulously clean. It is advisable not to use them at all, as
good sanitary wire-gauze strainers are inexpensive.

Fic. 61.—A clean cow. The dirt cannot adhere to this cow to so great an extent
as to the one shown in Fig. 60. (Bul. 84, IIl.)

If these conditions are complied with, and the separator
is kept in a good clean condition, the milk will have compara-

DISPOSITION OF THE CREAM 179

tively few germs in it. Some germs, however, will enter the
milk, and in order to keep them from developing, it is essential
to cool the cream or milk immediately. Low temperature
retards and practically prevents the development of germ life.
It is a well-known fact that when milk is kept cool, it will remain
sweet much longer than if kept at a high temperature. Two
milkings or skimmings should never be mixed unless both are well
cooled first. In order to cool cream quickly, it should be stirred
during cooling. ‘The ordinary four-gallon shot-gun cans are
good and suitable for keeping milk and cream. They have
a large cooling surface in proportion to their cubical content.
The milk or cream should be cooled as low as the water will
cool it, and even lower than this if ice is obtainable. In keeping
milk, the temperature should never go above 60° F. Cooling to
so” F., if it can be accomplished, is much more desirable for
keeping milk or cream in good condition.

If considerable milk is handled, it is well to provide a milk-
house. It should be built. large enough to contain the sepa-
rator, water-tank, and other utensils necessary for home butter-
making, such as a churn and butter-worker. There should be
plenty of windows on all sides to give good ventilation. The
water-tank should be connected directly with the well, so that
the water can be pumped directly to the tank holding the milk
and cream. From this place the water can be run out into the
stock-tank. ‘This arrangement allows the milk to be kept at
- the lowest possible temperature.

It is just as essential to cool the milk during the winter as it is
during the summer. By pumping water through this tank
practically all the time, the water in the tank will be kept from
freezing. It is well to keep the surface of the water higher
than the surface of the milk in the can. This will prevent the
milk from freezing so easily. If the cold is too severe, a tank-
heater can easily be secured which will moderate the temperature
a trifle.

Disposition of the Cream.—There are two ways of disposing
of cream on the farm: (1) selling it to creameries or other parties,
and (2) making it into butter on the farm. The former method is

180 FARM SEPARATORS

usually the most advantageous. Creameries, as a rule, are
better equipped to control the quality of butter. The price per
pound of butter-fat is usually about 2 cents below “ New York
Extras.” A few of the best creameries are able to pay more
than that.

Shipping of Cream.—If cream is sent or shipped to cream-
eries and central plants, it is essential that it be delivered as
frequently as possible, and that it be delivered in cans which
will help keep it in good condition. If cream is to be hauled
any great distance and exposed to the sun, it is advisable to use
special jacketed cans, which retard the transmission of heat.
It is a good plan to cover the cans with a wet sack or cloth during
the summer, and the use of a dry sack on the outside in the winter
often prevents the cream from freezing.

Making Butter on the Farm.—Ii cream is kept in good condi-
tion and proper skill is ap-
plied, the best of butter can
be made on the farm. The-
oretically, better butter can
be made on the farm than at
the creamery, because all
conditions can be controlled
better. In the creameries
one can of bad cream mixed
with a quantity of good cream
is likely to contaminate and
injure the whole lot. The
cream which is to be made
into butter on the farm should
not be over-ripened before
it is churned. In creameries,
starters are used to set up a
quick and desirable fermentation in the cream; conditions are
usually such on the farm that it is not convenient and practical
to use a starter. It is very essential that the cream be cooled to
a low temperature (50° F.) and left at this temperature for at
least two hours before it is churned; otherwise the butter is likely

Fic. 62.—A barrel churn.

MAKING BUTTER ON THE FARM 181

to be greasy and salvy. Butter should be colored and salted

to suit the market and
season. About one-half to
one ounce of salt to 1 pound
of butter usually gives
good results.

If a local trade can be
secured, it is not necessary
to pack the butter into
tubs. In this case it may
be kept in earthen jars.
If no local trade can be

Fic. 63.—Skinner butter-worker.

secured, and it is essential to ship the butter, 20- or 30-pound

Fic. 64.—Wizard butter worker (Creamery
Package Mfc. Co.)

tubs should be used. Ii a
good quality and constant
supply of butter can be
secured throughout the
whole year, it is an easy
matter to find an excellent
market at hotels or good
restaurants. (For a more
detailed discussion of but-
ter-making, see Chaps.
XVII and XVIII.) Putting
up butter in prints and

. Wrapping them in parchment paper which bears the maker’s
name usually increases its selling price.

182 FARM SEPARATORS

----L~

pi Pub ZONE

\
Se

Cross-section of bowl on line A—A.

az

<ZZZZZZZE

jp

CLZZLLZLL LLL

j LZZZZLELED,

AN

gy
A :
Sectional view of bowl.

Fic. 65.—Sectional views of International Harvester Co. Cream Separator.

NY

Qi

Z
_\

UT

LTT

\

oy

iS

CHAPTER XIV
NEUTRALIZATION

The “* Neutralization” of Cream

Neutralization.—The principle of neutralization is not a new
one. Its application in the laboratory is practically as old as
the science of chemistry, but its application to cream is compara-
tively recent.

The principle is easily explained and understood. In chem-
istry there are two large classes of substances which are opposite
to each other in action and have a strong affinity for each other,
namely, bases (which include alkalies) and acids. A base and
an acid, when brought together, react upon each other to form a
new substance which is neither an acid nor an alkali, and is
called a salt. For example, when hydrochloric acid and caustic
soda react upon each other common salt and water are formed,
thus,

HC wy - N2OH SF iNacl i> srs0

(Hydrochloric Acid) (Caustic Soda) (Common salt) (Water)

Again, when either quicklime or slaked lime (hydrate of lime)
reacts with hydrochloric acid they form calcium chloride, which
is the salt commonly used for making the brine used in connec-
tion with refrigerator systems, as it can be reduced to a very low
temperature without freezing.

CaOn, --) 2HiClay — CaClo + He20
(Quicklime) (Calcium chloride)
or
Ca(OH)2 + 2HCl = CaCl + 2H20O
(Slaked lime)

183

184 NEUTRALIZATION

A definite quantity of a given alkali will always neutralize a
definite quantity of a given acid. To take a concrete example:
If upon trial we find that it takes 8 c.c. of a certain alkali solution
to neutralize 10 c.c. of a given acid solution, subsequent trials
will show that they always combine with or neutralize each other
in exactly the same proportions. In a test of this kind we use
an “‘ indicator ”’ to tell us when the solution tested changes from
an acid to an alkali. If phenolphthalein be used it remains
colorless so long as the medium is acid, but as soon as the acid is
all neutralized and the liquid becomes alkaline to the slightest
degree, this indicator turns red. Litmus shows blue when the
medium is alkaline and red when it is acid.

The principle of neutralization has been applied in dairy
work for many years, in the form of the different alkali tests used
in cheese- and butter-making to determine the acidity of the milk
or cream. The reagent used is an alkali solution of known
strength, usually a caustic soda (NaOH) solution.

Lloyd, an English chemist, made use of it in connection with
his study of the principles and practice of Cheddar cheese-
making about thirty years ago, and Mann introduced his test,
which is still in quite common use, in 1890. The principle of
these different tests is the same. It is only in the details that
they differ.

In these acidity tests the acidity of the milk or cream is
reduced to the neutral point, or the point where the substance
tested is neither acid nor alkaline. This is true and complete
neutralization.

“ NEUTRALIZATION ” OF CREAM FOR BUTTER-MAKING

We now come to the use of the words “neutralization” and
“neutralizer” in a new sense, in connection with cream. What
is, in popular language, termed the “neutralization” of cream Is,
in reality, merely a lowering or reduction of its acidity to a point
at which the cream can be efficiently pasteurized, without causing
an excessive loss of fat in the buttermilk. The substances most
commonly used for the purpose of reducing the acidity are milk

“NEUTRALIZATION” OF CREAM FOR BUTTER-MAKING 185

of lime and soda ash. Neither of these alkalies should ever be
used to reduce the acidity of cream to the neutral point, as in
doing this there is grave danger of injuring the quality of the
butter made from it. The necessity for reducing the acidity of
cream came in with the general use of the little hand separator
on the farm. The volume of cream thus produced was small;
hence, the holding of cream at home until a sufficient volume
was accumulated for delivery resulted, in many cases, in cream
being delivered in a very sour condition, or in such a condition
that it could not be pasteurized unless the acidity was reduced.

There is some dispute as to who first used an alkali for reduc-
ing the acidity of cream so that it could be efficiently pasteurized.
We find that in 1896, Babcock and Russell of Wisconsin issued
Bulletin No. 54 explaining the preparation and use of viscogen
for the purpose of restoring cream for city trade to its natural
consistency, as in the process of heating the lime salts are thrown
down and the cream assumes a very thin appearance. Viscogen
is composed of cane-sugar and lime. We are told that one
creamery in particular used viscogen as a neutralizer in sour
cream at a very early date.

As far back as 1901-02, one of the authors conducted exten-
sive experiments in the use of alkalies of various kinds for
reducing the acidity of cream; and in so far as he knows he was
the first to take up experimental work in reducing the acidity of
cream for butter-making. Some butter-manufacturing firms, as
- early as 1905, used a lime preparation in the commercial manu-
facture of butter. Since then the practice has gradually grown
until now it is very general.

Why do we neutralize cream? The authors believe that there
is an entirely satisfactory answer to this pertinent question and
hope to be able to show that modern creamery conditions demand
and fully justify neutralization.

Butter, at best, is a perishable product—so much so that even
butter of the best keeping quality must be placed in cold storage
at a low temperature (close to 0° F.) if it is to be held any length
of time and retain its good flavor. The souring or ripening of
cream for butter-making has been practiced from time imme-

186 NEUTRALIZATION

morial. Many farmers’ wives have become so proficient in the
art of ripening cream and the making of butter that they have
gained an enviable reputation in their own communities. The
system of ripening or souring cream had been practiced by the
home dairies for a long time before alkali tests were used. At
this early date it was the custom to ripen or sour the cream until
it assumed a thick, granular appearance and had a pleasant
sour taste. The flavor that cream imparts to butter depends
upon the kind of organisms that predominate init. The obsery-
ance of sanitary methods on the part of the producer is con-
ducive to the presence of the right species of bacteria in the
cream. Cleanliness and sanitary methods should be observed
by the makers, whether in the private dairy or in the factory.
This is one of the first requisites of good butter-making; hence,
all good butter-makers, whether in the private dairy or in the
factory, observe cleanliness as a fast rule. Some butter-makers
have gained national reputations by exhibiting butter in state and
national butter contests, due to their ability to control the ripen-
ing of cream, by using pure lactic acid cultures in ripening to a
certain degree of acidity. One of the main causes of undesirable
flavors in cream is neglect on the part of the producers to thor-
oughly cleanse separators and other utensils that come in con-
tact with the cream on the farm, thus allowing undesirable
ferments to gain control. Another cause is neglect to cool cream,
immediately after separation, to a low temperature. No time
limit can be rightfully placed on the delivery of cream. Some
patrons deliver cream once or twice a week, even during the
summer, in such condition that the highest grade of butter can
be manufactured from it, while others deliver cream daily and
yet its flavor is such that it is impossible to make the finest
quality of butter from it. The quality of butter produced
depends upon the condition of the cream when it enters the
churn. The fact that cream may be high in acid when it reaches
the creamery is not an indication that poor butter will be made
from it. If the acidity of the cream is reduced so that the cream
can be efficiently pasteurized, a pure lactic acid culture can be
used again to ripen it, as only a small portion of the milk-sugar

“NEUTRALIZATION” OF CREAM FOR BUTTER-MAKING 187

has been converted into acid at the first souring. <A great deal
of cream arrives at the factories in too sour a condition to make
good butter unless the acidity is reduced. Hence, we can see the
necessity of using a harmless alkali for reducing the acidity.

The introduction of the farm or hand separator has revolu-
tionized the creamery business in America. While no reliable
statistics are available as to the number of separators used among
the dairymen of the country, it is estimated that go per cent of the
butter produced in the creameries of the country is manufactured
from hand separator cream. The principal reason for the gen-
eral adoption of the hand separator on the farms by American
dairymen was that they were always able to get sweet, warm
skim-milk for feeding the young stock. When milk was sent to
the creameries under the whole-milk system, it frequently hap-
pened through delays and other causes that the skim-milk would
be in a very bad condition for feeding purposes upon its return
to the farm. In addition to this, the lower cost of getting butter-
fat to the creamery in the form of cream greatly reduced the
expense. A can of cream has concentrated in it the fat of pos-
sibly ten or more cans of milk, and the cost per pound of fat for
shipping a considerable distance is small. Consequently, there
have been established large creameries equipped with the most
modern machinery, not only for the manufacturing of butter
but for utilizing the by-products as well. In addition to this,
many such concerns have cut out the middleman and thus
reduced the expenses of selling. Moreover, when a large volume
of business is conducted at one place, more skilled labor can be
employed. These are some of the reasons why the large or
centralized creamery has developed so rapidly.

It has been estimated that 80 to 85 per cent of our butter is
made from cream produced by farmers who are not dairymen
in the full sense of that term. Dairying with them is a side line.
Hence, the volume of cream produced is not sufficient to war-
rant its delivery to the creamery or buying station daily or even
every Other day. This means that a large volume of the cream
received at the central plant is sour to a greater or less degree,
although its flavor may be quite clean. When such cream has

188 NEUTRALIZATION

been “ neutralized ” by milk of lime and pasteurized, it can be

made into a very fine quality of butter. The president of a large
creamery company, possibly the second largest manufacturer
of creamery butter in this country, made a sworn statement that
during the year 1920 they manufactured 27 million pounds of
butter from cream that had been separated on the farms in
various states and that 25 million pounds out of the 27 million
pounds sold for extras or specials, some of it selling at a premium
even above specials. All this butter was made from cream of
which the acidity had been reduced by milk of lime. The fact
that cream can be shipped a long distance has been the means of
developing and stimulating dairying in sections of the country
where there was not enough cream available to supply a local
creamery. Where there is a sufficient volume of business to
sustain a local creamery, and the same is rightly managed, no
system will give greater returns to the producer. Whether a
creamery is local or centralized, the same condition prevails.

To make butter of the best keeping quality it is necessary
that the cream be pasteurized. Local creameries, as well as the
large creameries, receive some very sour cream, but not usually
in as great proportion. If such cream is to be pasteurized, it is
essential that the acidity be reduced. Investigations conducted
by the Dairy Division of the Federal Government and others
have demonstrated that butter made from cream with a low
acidity possesses better keeping qualities when placed in storage
than butter made from cream having a high degree of acidity.
Reducing the acidity of cream to the right point is a problem
that necessitates intelligent care and an understanding of the
effects of the use of an alkali. Cream that has been exceedingly
high in acid, which has been reduced by limewater or some other
harmless alkali substance, cannot be re-ripened with safety to
the same degree of acidity as sweet cream that has never had its
acidity reduced. Investigation has not revealed any satisfactory
explanation of this fact. It would seem that the alkali used for
reducing the acidity does not penetrate all the particles of cream,
or, in other. words, that the cream is not in a perfectly liquid
condition. Some cream received at the factories is very sour

“NEUTRALIZATION” OF CREAM FOR BUTTER-MAKING 189

and lumpy. It may be that the solution used does not come in
contact with the acid encased in the lumpy cream or particles
of cream.

To get the best results from neutralization, a large fore-
warmer should be used and the cream heated to 85° to 90° F.,
and thoroughly mixed by keeping the coil moving before and
while adding the neutralizer. The neutralizer should be dis-
tributed as evenly as possible throughout the entire mass so
that it will come in contact as far as possible with all particles of
the cream.

Butter made from high-acid cream, whether pasteurized or
unpasteurized, has a tendency to develop a pronounced fishy
flavor when placed in storage. It is difficult to pasteurize sour
cream if its acidity has not been reduced, as the heat causes the
cream to become stringy or ropy, due to the coagulation of the
casein. - This is particularly true with thin cream. If the acidity
of cream is high and it is churned in this condition, without having
the acidity reduced, butter. made from it will invariably be sour.
This will not impair its food value nor will it make the butter
injurious to health, but it will impair the flavor. Large classes
of people in America and the European countries spread their
bread with sour cream and regard it as a delicacy. The health-
fulness of buttermilk, koumiss, and other fermented milks is
- well known.

In investigations pursued in the laboratory of the American
Association of Creamery Butter Manufacturers on the heavy
losses of butter-fat in buttermilk, it was found that the fat-
globules that escape in the churning process and pass off in the
buttermilk are the small globules which are encased in the meshes
of the casein. The precipitation of the casein by heat in the
process of. pasteurization, where the acidity of the cream has not
been reduced, causes extreme losses in the buttermilk. In some
instances as much as I or 2 per cent of fat is found in buttermilk
made from such cream. Hence, the reduction of the acidity
for pasteurization is a necessity from an economic standpoint,
if for no other reason.

Sour cream isa farm problem. Every creameryman would be

190 NEUTRALIZATION

pleased to get cream in such a sweet condition that it would not
be necessary to reduce the acidity for pasteurization. The
alkalies most commonly used for reducing the acidity of cream
are limewater and soda ash. The authors have never recom-
mended the use of any other substance than limewater or milk
of lime. The amount of lime used in reducing the acidity, some-
what less than one-tenth of 1 per cent, is so infinitesimal that
it passes off in the buttermilk and has no effect upon the butter.
The fat-globules of milk being coated with a film, the alkali
solution used for reducing the acidity is mixed with the serum
or the other component parts of cream rather than the butter-fat;
hence, the small per cent of lime used practically all passes off
with the buttermilk.

Investigations pursued under the direction of one of the
authors showed that butter made from cream of which the
acidity had been reduced by milk of lime did not contain any
more lime than butter made from whole milk to which no lime
had been added, and contained less lime than a number of
samples of dairy or farm butter. Investigations of this butter
were made at the Universities of Wisconsin, Cornell and Purdue.
The explanation of the higher percentage of lime in dairy butter
may possibly be that the cream for the farm butter was churned
at a higher temperature than the cream from which the butter in
the creameries was made. Butter churned at a high temperature
will invariably contain a high percentage of casein. In such
butter the lime will be held between the meshes of the casein;
hence the high percentage of lime found in dairy butter, where no
lime had been added to the cream, was undoubtedly due to the
high temperature at which the cream was churned. Butter
made from cream which has been subjected to reduction of
acidity and pasteurization seems to give good satisfaction in the
markets. This is particularly true during the storage season.
Such butter is then sought by dealers in storage butter, owing to
its excellent keeping qualities.

The use of limewater in milk is of long standing and well
known. Lime is an essential constituent of dairy products. It
is there to build the bones and to serve other essential physio-

“NEUTRALIZATION” OF CREAM FOR BUTTER-MAKING 191

logical purposes. Lack of lime causes not only rickets in the
young, but also serious physiological disorders in the adult.
Some physiologists urge the addition of lime to the diet. Its
importance is thus expressed by Dr. Sherman of Columbia
University:

“Calcium is present in still greater abundance. Milk con-
tains slightly more calcium, volume for volume, than does lime
water. Asa rule the calcium content of the diet depends mainly
‘upon the amount of milk consumed. In family dietaries where
ordinary quantities of milk are used, the milk is apt to furnish
about two-thirds of the total calcium of the diet. Without milk,
it is unlikely that the diet will be as rich in calcium as is desirable
either for the child or for the adult.”

In their recent Circular, No. 11, the United States Depart-
ment of Agriculture and the United States Food Administration
state their conception of the need of lime as follows:

“Milk gives your children lime and other salts which they
need. There must be plenty of lime in their food, for a great
deal of it is needed for their bones and teeth and a little for their
blood and al] other parts of their bodies. Right food, not drugs,
is what children need. Big boys and girls and grown people,
as well as children. need lime, because the bones are constantly
wearing away little by little and must be replaced.”

Milk is the chief food for lime. It is much richer in it than
other common foods. ‘These lines stand for lime, the top one for
the lime in a cup of milk, the others for the lime in a serving of
some other foods. Notice how much more there is in milk than
in the others.”

AMOUNT OF LIME IN

I cup of milk
EE ST AE Aa 2 CER OT LI

= cup of carrots

I egg

2 slices of bread

192: NEUTRALIZATION

THE PREPARATION AND USE OF LIME AS A NEUTRALIZER

While there are other preparations, as those of the sodas,
which are sometimes used for the neutralization of cream, the
present discussion will be limited to the preparation and use of
lime compounds as neutralizers.

Before proceeding with this, however, the authors would
digress a little to give the results of analyses made of different
samples of lime in the laboratory of the American Association of
Creamery Butter Manufacturers. Eleven samples of lime from
various parts of the United States were analyzed to ascertain
their fitness for reducing the acidity of cream. The solubility
of the limes in a o.7 per cent lactic acid solution and their neu-
tralizing power in terms of lactic acid were determined. The
investigators were surprised to find that this amount of chemical
work revealed very little more than was evident to the senses,
aided by common sense. Here follow a few typical exhibits:

Silica | Volatile,|Iron and Mae
s ‘ (Sand) Clay, |Calcium aee
\ 5) 5)
No.| Kind Quality Per Per Per Oxide ote Total

Cent Cent Cent a
4 |Hydrated| Good 0.31 II.45 °.73 | 88.60 © |I00.00
tr |Quick Good o. 26 A Wf5; 1.56 | 93.40 ° 99.97
6 |Quick Good 0. 36 7.00 1.25 || 58.20) | 33. 5455 noomas
3 (Quick Poor 2.43 Tass 6.44 | 55.40 | 34.19 | 90.81

No. 11 is a high calcium lime. Nos. 3 and 6 are magnesian
limes. Although the percentages of calcium in 11 and 3 differ
widely, they both give good results in reducing acidity. Mag-
nesia acts like lime and is not as.much inclined as lime to flavor
the butter. It has a greater neutralizing power than calcium.
No. 3 contained too much silica (sand), clay and iron. This ~
was just as discernible by a physical inspection as by chemical
analysis. The sand could be seen and felt and the clay made a
granular yellow mixture.

There are two forms of lime that are used in the preparation
of neutralizer, namely, quicklime in lump or in powder form, and
hydrat€d lime, which is quicklime slaked by the lime-maker

THE PREPARATION AND USE OF LIME AS A NEUTRALIZER 193

instead of the user. As is shown below, it takes 74 pounds of
completely hydrated lime to equal 56 pounds of quicklime for
neutralizing purposes. Of course, the hydration is often only
partial and then the difference is not so great.

It is really a lime mixture in the form of milk of lime, and not
limewater, that is used, as lime is only soluble to a very small
extent in water, and it would require too much of this to make its
use practicable.

Lime should be free of such impurities as sand, clay and iron,
and the lime preparations offered by responsible firms for neu-
tralizing purposes usually are.

It is very important that the lime mixture be properly pre-
pared. Much more trouble arises from improper preparation
than from defects in the lime itself.

Quicklime is obtainable in powder form, packed in tin canis-
ters. This form gives excellent satisfaction, as the quicklime is
clean, uniform and free of waste material, and keeps until it is
all used; whereas in lump lime there is considerable waste,
through air slaking and the rejection of unsuitable lumps.

A very suitable mixture is made up in the proportion of 17
pounds of water to 3 pounds of quick lime. The water should be
_as near boiling as possible and the lime should be added to the water
and not the water to the lime. ‘The lime should be added in four
installments instead of all at once, and the mixture stirred thor-
oughly after each addition of lime. If properly prepared the
mixture will be very smooth and free of visible lime particles.
When cool, it may be tested by putting the hand or a smooth
butter spade into it and withdrawing. If smooth, showing no
lime particles, it is a good mixture; if it shows a very few par-
ticles, it is fair; and if it shows many particles it is a poor mixture
and is more likely to impart a limy taste than is a smooth mix-
ture. A good mixture properly added to and mixed with the
cream, and not in excess, is not nearly so likely to impart a limy
taste to the butter.

A mixture of 3 pounds of lime to 17 pounds of water is the
same as 15 pounds of lime to 85 pounds of water, or a 15 per cent
mixture.

194 NEUTRALIZATION

Whether one proceeds scientifically or mechanically in the
preparation of his lime mixture, his work is based upon the fol-
lowing:

Molecular weight of quicklime, CaO, is 40+16 =56.
Molecular weight of hydrated, Ca(OH), is 4o+2(16-+1) =474.
Molecular weight of lactic acid, C3H6Os, is

(3 X12)+6+(3 X16) =g0.

But the limes are bivalent. Hence 56 pounds of quicklime
or 74 pounds of slaked lime will neutralize twice 90, or 180 pounds
of lactic acid.

Hence 1 pound of lactic acid is neutralized by 338;=.3111
pound quicklime.

It takes 2.074 pounds of a 15-per cent mixture of quicklime to
supply .3111 pound of quicklime. Hence 2.074 pounds of the
quic!iime mixture will neutralize 1 pound of lactic acid, or reduce
the acidity of tooo pounds of cream o.1 per cent; and it is upon
this figure, which is theoretically correct, that the following table
is based:

TO REDUCE THE ACIDITY OF CREAM TO .25 PER CENT

InrtrAL Acrpity OF CREAM

Lm P35 e400 S45) 50) 55) OOMHOSi 170) na 75CONs OS MOONS
Pounps of 15 Per Cent Lime Mixture NEEDED
oo sil oA) 38 ma SH SO ofA) oS SOll oO) Won] Boal WLS} 2.5
500 Bis|| angel con} a sel Olena al) Meri ioral a eo Cae Oo 7) 7-3
1000 I.0] 2.1] 3.2| 4.1) 5.2) 6.2) 7.3] 8.3) 9.3/10.4/11.4/12.4/13.4] 14.5
1500 TiS Bom AoW Oo2l) Woy 9.3/10.9|12.4|t4.0/1s.6|r7.2 18.7|20.2| 21.8
2000 2.1) 4.1| 6.2] 8.3:10.4|)12.5|14.5|16.6)18.7|20.7 22.8124.9127.0 29.0
2500 2.6] 5.2 7-8'10.4/13.0)15.6)18.1'20. 7/23. 3)25.9/28.5|31.1/33.7 36.3
3000 3-1| 6.2] 9.3/12.4/15.5|18.7)21.8 24.9 28.0)31.1/34. 2137 3/40-4) 43.6
3500 3.6] 7.2|10.9|14.5|18. 1/21. 8/25. 4/29.0/32. 7/36. 3139.9143.6147.2| 50.8
4000 4.1| 8.3,12.4)16.6)20. 7 24.9 29.0133. 2/37-4141-5145-7/49-8153-9 58.1
4500 4.6] 9.3|14.0|18. 7)23.3!28.0132. 7137-3/42-0/46. 7151. 3156.0,60.6) 65.3
5000 5-2|10.4)15.6 20.7/25.9|31.1/36.3/41.5/46.7 5t-8)57.062.2,67.41 72.6
5500 5.711. 4|17. 2/22.8128.5 34. 2|39-9145.651.3'57-0/02.7,08.4;74.1| 79.9
6000 6.2)12.4/18. 7/24.9)32: 1137-3143. 61490 8)56.0/62. 2/68. 4/74. 7,/80.9 87.1
6500 6.7|13.5/20.3 27.0|33.7|40.4|47.2|53.9|60. 7/67. 4174. 1/80. 9/87.6 04.4
7000 7.3|14.5)21.8)29.0/30. 3/43. 6/50. 8)58.1 ak aac 94.4)101.6
} |

THE PREPARATION AND USE OF LIME AS A NEUTRALIZER 195

The common practice in creamery work is to measure the
lime mixture, in adding it to the cream, instead of weighing it. In
case this is done the mixture should be made up so that there
will be 12.5 pounds of quicklime in ro gallons of the mix, that is,
this quantity of lime should be mixed with about 8 gallons of hot
water and then brought up to 10 gallons by adding sufficient hot
water. This water to be added should be heated in an open vessel
so as to drive off any carbonic acid gas there may be in it, and
should not be added directly from a hose or tap.

In 10 gallons of the mixture there are 12.5 pounds lime.
1D 6 fs

4

= “= .3125 pound lime.

In 1 quart of the mixture there is

We have already shown that .3111 pound quicklime will
reduce the acidity of 1000 pounds cream .1 per cent. Hence, 1
quart of the lime mixture, which contains .3125 pound quicklime,
-UX.3125

Ania |
per cent =.1 per cent practically. Or, 1 pint of the lime mixture
will reduce the acidity of 1000 pounds cream .o5 per cent. It
is upon these figures that the table on page 1096 is based.

How many pints of lime mixture will it take to reduce the
acidity of 3400 pounds of cream from .70 to .25 per cent? In the
column under .7o and opposite 3400, this is given as 30.5 pints.
The same quantity of lime mixture would be used for all acidities
nearer to .7o per cent than either .65 per cent or .75 per cent.
This principle applies all through the table.

Note the simple numbers opposite 1000 pounds of cream.
The quantity of mixture required for any weight of cream can be
quickly determined by multiplying the weight of cream by the
amount of mixture required to reduce the acidity of 1000 pounds
of cream to .25 per cent and dividing by 1000 (or pointing off
three decimal places). Example:

How many pints of lime mixture will be required to reduce the
acidity of 6300 pounds of cream from .80 per cent to .2 & oer CeIn

tooo pounds of cream require 11 pints of mixture.

6300 pounds of cream require 11 X6.300 = 69.3 =69.5 pints of
mixture.

will reduce the acidity of 1000 pounds cream TOO4

196 NEUTRALIZATION

PINTS OF LIME MIXTURE REQUIRED TO REDUCE ACIDITY TO
25 PER CENT

PER CENT OF AcID IN CREAM

Lbs. of
Cream}].30] .35| -40| .45) -50| -55| .60| ..65| .70] .75| .80] .85] .g0| .95|/r.00
aoe) SH ote te adsl hve by -5| e)| 140} HeO}) WoO] Hao) Woh] NOG) #5
200 5S oS WoO) MeO} UO] H25)) ToS] 2.0) 2.6] 2.6) 2.5] 2.8] 2.6] 3.0
Clelh ESI WSS e OCI Ay A AdO)| Aare) aS ak) cisel! Sap sesi| Al] Ace) 4.5
4oo | .5| 1.0] 1.0] 1.5] 2.0} 2.5] 3.0] 3.0] 3.5] 4.0] 4.5) 5.0] 5.0] 5.5| 6.0
BOO) ||. S| LO] Test 2.0" 2h) 310) bans) AO AS 55) Ole5 5 OOO: 5 leqisO mais
600) || -5| 1-0} 2.0} 2) 5) 3.0] 325) 4-0] 5.0] 5.5! O20] 16.5 7x0) S.0)) 8a5|hon0
70O | .5| 1.5] 2.0) 3.0] 3.5] 4.0] 5.0] 5.5] 6.5] 7.0] 7.5] 8.5] 9.0|10.9]10.5
800 |1.0] 1.5] 2.5] 3.0] 4.0] 5.0] 5.5| 6.5] 7.0; 8.0] 9.0] 9.5/10.5|/11.90/12.0
Clore inl soll Merl esi Aes) Gad Oss) 7oCi sO} Oacliorn elem aC Ht 2 Gin.
IOOO |1.0] 2.0] 3.0] 4.0] 5.0] 6.0] 7.0] 8.0] 9.0]10.0]11.0]12.0]13.0]14.0/15.0
IIOO |1.0] 2.0, 3.5] 4.5] 5.5] 6.5] 7.5] 9-O|10.0/1L.0/12.0/13.0/14.5/15.5/16.5
1200 |I.0; 2.5] 3.5] 5.0] 6.0] 7.0] 8.5| 9.5/II.0]12.0/13.0]14.5|15.5/17.0|18.0
1300 |1.5| 2.5] 4.0] 5.0] 6.5] 8.0] 9. 0/10. 5/11. 5|13.0]/14.5]15.5|17-0]18.0119.5
1400 |1.5| 3.0] 4.0] 5.5] 7-0] 8.5/10.0/11.0/12.5/14.0/15.5|17.0|18.0]19.5/21.0
1500 |I.5| 3.0] 4.5] 6.0] 7.5] 9.O]10.5/12.0)13.5|15 0]16.5)18. 0/19. 5/21.9/22.5
1600 |1.5} 3.0) 5.0] 6.5) 8.0] 9.5]11.0/13.0)14.5|16.0/17.5)19.0]21.0)22.5|24.0
1700 |1.5|] 3.5] 5.0] 7.0| 8.5|10.0/12.0/13.5]15.5|17-0|18. 5/20. 5|/22.0)24.0/25.5
1800 |2.0] 3.5] 5.5| 7.0] 9.0|11.0/12.5|14.5|16.0118.0|20. 0/21. 5/23. 5/25 .0|27.0
1900 |2.0] 4.0] 5.5] 7.5] 9.5|11-5|13.5|15-0|17.O|19.0/21.0|23.0/24.5|26.5|28.5
2000 |2.0| 4.0] 6.0| 8.0/10.0|/12.0|/14.0|16.0/18.0|20.c}22.0/24.0/26.0/28.0/30.0
2100 |2.0| 4.0] 6.5] 8.5|10.5)12.5|14.5|17.0|19.0|21.0/23.0/25.0/27- 5/29. 5131.5
2200 |2.0| 4.5] 6.5] 9.0|/I1.0|13.0|15.5/17.5|20.0|22.0|24.0/26. 5/28. 5/31 .0/33.0
2300 |2.5] 4.5] 7.0| 9. 0/12. 5|14.0|16.0|18. 5/20. 5/23.0/25.5|27.5|30.0/32.0/34.5
2400 |2.5] 5.0] 7.0] 9.5/12.0|14.5|17.0|19.0/21.5/24.0/26. 5/29. 0/32 .0]/33.5/36.0
2500 |2.5| 5.0) 7.5|10.0|12.5|15.0|17.5|20.0/22.5/25.0/27.5|30.0/32-5|35.0/37-5
2600 |2.5; 5.0] 8.0/10.5/13.0)15.5|18.0|21.0]23. 5/26.0/28. 5/31 .0/34.0/36.5/39.0
2700 12.5) 5.5| 8.o|1r.0|13.5|16.0]19.0)/2T. 5/24. 5/27.0]29. 5|32.5|35-0/38.0/40.5
2800 13.0: 5.5] 8.5)1T.0|14.0|17.0|19. 5/22.5|/25.0/28. 0]31.0]33. 5|30-5/39-0/42.0
2900 |3.0| 6.0] 8.5/11.5|/14.5/17.5|20.5|23.0/26.0/29.0/32.0/35.0]37- 5/49. 5/43-5
3000 |3.0| 6.0] 9.0/12.0/15.0|18.0/21 0]24 0/27. 0/30.0|33.0/30.0/39.0/42.0/45.0
3100 |3.0| 6.0] 9.5/12.5|15.5|18.5/21.5/25.0/28.0/31.0/34.0/37.0/40- 5143. 5|40.5
3200 |3.0) 6.5] 9.5|13.0|16.0/19.0/22.5/25.5/29.0/32.0/35.0/38.5/41.5|45.0/48.0
3300 |3.5| 6.5|10.0'13.0|16. 5!20.0]23.0/26. 5/29. 5|33.0136. 5|39-5|43-0/40.0/49.5
3400 3.5] 7.0/10.0113.5 17.0|20.5|24.0|27.0/30.5|34.0/37.5|41.0/44.0/47.5|51.0
3500 |3.5| 7.0/10.5/14.0]17.5|21.0/24. 5/28. 0/31. 5/35 .0/38.5/42.0/45.5|49.0/52.5
3600 |3.5| 7.0]11.0/14.5|18.0}21.5|25.0/29.0|32.5/36.0/39.5|43.0|47.0/50.5/54.0
3700 13.5) 7.5|11.0|15.0]18.5|/22.0|26.0/29. 5|33-5/37.0140.5/44.5148.0/52.0/55-5
3800 |4.0! 7.5/I1.5:15.0|19.0/23.0 26. 5/30. 5/34.0/38.0/42.0/45 . 5/49. 5 53.0|57-0
3900 |4.0| 8.o0]11.5|15.5/19.5/23.5/27-5/31-0135 .0/39.0/43.0/47.0|50.5)54.5|58-5
4000 |4.0| 8.0|12.0:16.0/20.0|24.0 28 .0|32.0:36.0]40.0/44.0|48.0/52.0156.0|60.0
4100 |4.0| 8.0/12.5/16.5|20.5/24.5 28. 5|33.0137-0141.0145.0149.0)53.5|57.5/O1.5
4200 |4.0| 8.5|12.5|17.0)21.0|/25 0/29. 5/33. 5|38-0|42.0|46.0|50. 5/54. 5/59.0|03.0
4300 |4.5| 8.5|13.0|17.0|21.5|20.0/30.0/34. 5/38. 5/43.0]47.5|/51.5|50.0|60. 0/64. 5
4400 |4.5| 9.0|13.0|17.5|22.0|26. 5/31 .0]35 .0/39-5/44.0/48. 5|53.0/57.0/01.5|06.0
4soo |4.5| 9.0|/13.5)18.0]22.5/27-0|31.5|30.0|40. 5/45 .0/49.5|54.0/58.5/63.0/67-5
4600 14.5) 9.c]I4.0/18.5)23.0/27.5/32 0/37.0/41.5146.0]50.5|55.0|60.0/64.5|69.0
4700 |4.5) 9.5|14-0|19.0/23.5|28.0/33.0137.5|42-5)47.0]51. 5/50. 5|61.0/66. 0/70. 5
4800 |5.0| 9.5/14.5/19.0|24.0/29.0/33.5138.5]43-0/48.0]53.0|57-5|62.5|67.0|72.0
4900 |5.0|10.0]14.5/19.5|24.5/29.5)34-5|39-0/44.0/49.0154.0/59.0/63. 5/68. 5173-5
5000 5.0'10.0|15 .0|20.0)25 .0]30.0]35.0)40.0/45 .0]50.0]55 .0|60.0/65.0/70.0)75-9
6000 |6.0/12.0/18.0 2400/8079) 30- 0/42) 0/48) 2154-90 .< belie 0/78 .0/84.0}90.0

THE PREPARATION AND USE OF LIME AS A NEUTRALIZER 197

This is a general solution which applies to any weight of
cream.

Where lime is completely slaked or hydrated it takes a little
over 32 per cent more of it than of quicklime (74 pounds as against
56 pounds) to make the same strength of mixture. As the mix-
ture upon which the table (p. 196) is based contains 12.5 pounds of
quicklime to ro gallons, it would require 16.5 pounds of hydrated
lime to to gallons to make the same strength of mixture. If
the lime is only partially slaked it will, of course, take less than
16.5 pounds.

The quantities of lime indicated for making the mixture are
theoretically correct, but the individual user will be obliged to
determine by test whether the mixture is right in strength for his
cream. It may be necessary to use a little more or a little less
lime than indicated, in making the mixture, probably a little less
if any change has to be made. If necessary, a slight change may
be made in the strength of the mixture to avoid changing the
table.

In investigations conducted by Hunziker, in which he used
the strength and quantity of lime mixture supposed to be suf-
ficient to reduce the acidity of the cream to .25 per cent, he
secured the following average resulis:

Per Cent
inant aciaitygon Cheats tt: Galo Yo ANS. oe Selb te ee. TS
Acidity three hrs. after neutralizing, pasteurizing and cooling. . 33

Tn other words, whereas the acidity should have been reduced
by .50 per cent (.75—.25) it was only reduced by .42 per cent
(.75—.33). This means that (33—25)+50 or sy9=16 per cent
of the neutralizer was not used, or that this mixture would need
to be strengthened to the extent of the addition of 15 to 20 per
cent more lime.

On the other hand, Hunziker found that when enough lime
mixture was added to a pure lactic acid solution to theoretically
reduce its acidity to .25 per cent it actually did reduce it to this
point. The conclusion he reached, through his investigations,
was that some of the lime added to cream attaches itself to the

198 NEUTRALIZATION

casein and therefore all of it is not used up in the neutralization
of the lactic acid in the cream.

The strength of a milk of lime mixture can be increased in
either of two ways, (a) through the use of a larger proportion of
lime, (0) through the use of lime containing a larger proportion of
magnesium oxide, which is stronger, pound for pound, than
calcium oxide.

When a lime mixture is made up in small quantities, a ten-
gallon can will suffice for this purpose. But where larger quan-
tities are required a cylinder-shaped tank similar to a starter
tank, with an agitator in it, should be used. This can be of any
suitable capacity, say 100 to 200 gallons. A simple gage may be
used for measuring the contents. The user must remember that
he is dealing with a mixture and not a solution, and that not
only must there be a thorough agitation at the time the mix-
ture is made but this must be repeated, to a lesser degree, when-
ever any of the mixture is used, as the lime settles.

Although the best limes do not contain 100 per cent calcium
oxide, they usually contain enough magnesium oxide, which is
stronger pound for pound than calcium oxide, to make up for this
shortage.

There are some points that should be kept carefully in mind
in the preparation and use of neutralizers.

The lime does not act so quickly and completely that its full
effect is secured immediately. For this and other reasons, the
acidity of the cream after pasteurization is lower than it was
before pasteurization. The amount of drop in acidity varies
with the cream, lime mixture and locality.

Some creameries add the lime mixture directly to the cans of
cream. Some run it by a faucet into either the dump vat or the
pasteurizer. Others fill a supply vat or forewarmer and then
reduce the acidity to the desired point. The last method is the
best.

The authors believe there is yet considerable to be learned
about methods of applying neutralizer to cream in order to
secure the best results and avoid unnecessary losses of fat in the
buttermilk.

THE PREPARATION AND USE OF LIME AS A NEUTRALIZER 199

A careful determination of the acidity of the cream should
always be made both before adding the neutralizer and after it is
pasteurized and cooled. It may be found necessary to reduce the
acidity of the cream a little more, or on the other hand it may be
found that the acidity of the cream is being reduced too
much. This determination will thus act asa guide for future
work.

If the cream is to be ripened again the acidity is usually
reduced to 0.15 per cent to .22 per cent (9° to 12° Mann’s) and
then ripened to the desired acidity.

Some prefer the use of slaked or hydrated lime. While hot
water must be used in the preparation of the quicklime mixture,
the hydrated lime should always be mixed with cold water.

OTHER NEUTRALIZERS

Some creameries use carbonate and bicarbonate of soda—
commonly spoken of as soda ash—as neutralizers. The soda
ash is very soluble in water and forms a clear liquid solution.
This is more easily made and added to the cream than is the lime
mixture, and doubtless this is the main reason for its use.

What has already been said indicates the authors’ preference
for the use of lime as a neutralizer and the reasons for this
preference. The following points may therefore be treated
briefly :

Lime is something that is well known and generally regarded
as clean and wholesome, and the use of it in the neutralization of
cream will not offend, in the slightest degree, the susceptibilities
of the most fastidious.

Attention is frequently drawn, by physiologists, physicians
and students of dietitics, to the necessity for a liberal supply of
lime in the diet of children and adults, and to the fact that in
many foods there is a shortage of this constituent.

Limewater is commonly used as an accessory to and a cor-
rective of the foods of hospital patients and of children and
infants.

While it is true, as has already been pointed out, that the

200 NEUTRALIZATION

lime used in the cream passes off in the buttermilk, yet it is
important that the consumer feel assured that the substance
used as a neutralizer is something which is not foreign to milk,
cream and butter and is wholesome, and to which no objection
can be taken.

CHAPTER XV
PASTEURIZATION

Definition.—As applied to butter-making and city milk, pas-
teurization may be defined as a process of heating milk or cream
to a temperature sufficiently high to destroy the great majority
of the bacteria and other ferments contained therein and cooling
it quickly to a low temperature. The name is derived from
Louis Pasteur, an eminent French scientist, who made the dis-
covery in the years 1860-64, that if wines were heated to a certain
temperature (70° C. or 158° F.), and cooled again, fermentation
would stop.

In 1884 Soxhlet applied the method of heating to milk for
destroying bacteria.

Storch Test for Pasteurization.—Storch, at the Royal
Agricultural Experiment Station, Copenhagen, Denmark, was
the first to apply general pasteurization to cream for butter-
making. Denmark has a law making pasteurization com-
pulsory. This law was enacted to prevent the spread of tuber-
culosis among the herds. The law requires that milk or cream
must be heated to 80° C., or 176° F._ Samples of skim-milk from
the creameries are required to be sent to the Experiment Station
where they are tested by the Storch test to ascertain if creameries
are complying with the requirements of the law.

Storch found that of all the reagents that might be used for
determining whether milk or cream had been heated to 80° C. or
176° F., the best was paraphenylene diamine. This compound
ordinarily gives a brown color when acted upon by “ active ”
oxygen, but in the presence of casein in milk the color is a beau-
tiful indigo blue.

To carry out the test about 5 c.c. of milk or cream are put

201

202 PASTEURIZATION

into a test-tube and one or two drops of a 0.2 per cent solution of
hydrogen peroxide is added from a dropping bottle, also two
drops of a 2 per cent solution of paraphenylene diamine, from a
dropping bottle. Brown dropping bottles should be used to
prevent the light from weakening the reagents. The test-tube
is then well shaken, and if the milk has not been heated above
78° C., or 172° F., or if not heated at all, an intense blue coloration
is produced. If at once or after half a minute the milk becomes
bluish-grey, it indicates that it has been heated to a temperature
of 78° C. to 80° C., or 172° F. to 176° F. When the color of the
milk is unchanged after addition of the reagents, it may be
concluded that the heating has exceeded 80° C. The blue color
that develops on standing has no significance.

Storch’s test has shown itself to be the most reliable of all the
methods proposed for distinguishing heated from unheated
milk. All the so-called improvements which have been advo-
cated by other chemists have proven to be of no benefit, often
indeed the opposite.

If during the pasteurization of the milk the temperature falls
below 80° C. for a time, the whole of the milk after being mixed
reacts to Storch’s test. The sensibility of the test is so great
that the admixture of 10 per cent of milk which has only been
heated to 78° C., suffices to make the whole volume of milk react
to the test.

Pasteurization Temperatures.—In pasteurizing or heating
milk for city trade or immediate consumption, low temperatures
are used. This is done for the purpose of avoiding a cooked or
heated taste. The method found most satisfactory for milk is
to heat to 145° F., and hold at this temperature for twenty
minutes. This is known to the trade as the holding method.

Where the flash or instantaneous method is used, the milk or
cream is heated to a temperature of 175° to tco° F. The tem-
peratures most commonly used in butter-making in creameries
are 180 to 185° F. Of late years the higher temperatures have
been used for butter-making, even in the holding method.

Marker, in the Canadian Northwest, recommends heating to
170 or 175° F., and holding for fifteen or twenty minutes. This

PASTEURIZATION TEMPERATURES 203

method of heating has been recommended by him for the pur-
pose of destroying the enzymes in the cream. Butter made from
cream thus treated has shown unusually good keeping qualities,
and he reports that it does not go fishy when placed in storage.
One of the advantages of pasteurization is that it destroys all the
pathogenic micro-organisms in the cream if any be present.
Efficient pasteurization destroys from 99.5 to 99.9 per cent of
the organisms present in cream. Pasteurization, however, does

Fic. 66.—The Simplex regenerative pasteurizer (apart).

not put poor cream in a condition where good butter can be
made from it.

Pasteurization and sterilization are not the same. The
latter means that milk or cream, or any other liquid substance,
has been heated so often or to a high enough temperature to
entirely destroy every living micro-organism present. In order
to get a substance thoroughly sterilized without heating under
pressure, it is essential that it be heated about thirty minutes
on each of three or more consecutive days.

204. PASTEURIZATION

Good Milk and Cream Important.—The quality of butter
made from pasteurized cream will depend to a very large extent
upon the condition of the milk or cream used. If milk or cream
is sweet and free from obnoxious flavors at the time of pas-
teurization, the quality of the butter made from it will be good,
provided that the butter is not injured in the process of manu-
facturing. The quality of the cream used has a bearing not only
upon the quality of the butter made from pasteurized cream but |
upon that made from unpasteurized cream as well.

The impression prevails to some extent that butter made
from raw cream will not possess keeping qualities and that if
placed in cold storage it will develop a fishy flavor. Investiga-
tions pursued by one of the authors do not bear this out. In
t907 he conducted a series of experiments at Strawberry Point
Creamery, Strawberry Point, Iowa, during the month of July.
This experiment was conducted under regular creamery con-
ditions, and was carried on for a period of two weeks. Apparatus
was moved from the Iowa Experiment Station for making com-
plete analyses of the butter and records of everything pertaining
to this work were kept. The Strawberry Point Creamery at this
time was receiving about 50,000 pounds of milk daily. The milk
was received from the patrons in cylinder-shaped 20-gallon cans.
It was inspected at the wagons, and any milk found slightly sour
or tainted was rejected. Power separators were used for sep-
arating the cream from the milk, and the cream separated con-
tained a high per cent of fat, the fat-content, after starters had
been added, varying from 37 to 39 per cent. The cream used was
in as perfect a condition as cream delivered for butter-making
purposes can possibly be. Pure culture starters were used for
souring or ripening it. About half the butter was made from
unpasteurized cream, and the other half from pasteurized cream.
In every case, two different churnings of butter were made
from the same vat of cream, or the cream was divided so that two
separate churnings were made. The full object of the experi-
ment will be dealt with in another chapter. Two 60-pound tubs
of butter were packed from each churning and-shipped to Gude
Bros., New York City. Each one of these tubs bore a special

GOOD MILK AND CREAM IMPORTANT 205

number. When the shipment of butter arrived in New York,
half was to be sold in the open market and the other half placed
in cold storage. Three 56-pound cubical boxes were also packed
from each churning; one of these boxes was shipped to London,
England, one to Liverpool and one to Manchester, for the pur-
pose of having the best English experts score and criticize the
butter. The butter sent to New York was scored before going
into cold storage, and it was rescored when it came out of storage
by Mr. P. H. Keiffer, who is generally recognized as an excep-
tionally good judge of butter. One of the authors was present
in New York when this butter came out of storage. Strange to
say, both the pasteurized and unpasteurized butter, after being
in storage between six and seven months, came out of storage
scoring as high as when they entered storage. Mr. Keiffer
remarked that it was the finest lot of butter he had ever seen
come out of storage at that time. No difference was found in
the English market between the scores of the pasteurized and the
unpasteurized product. One of the English judges scored some
of this butter too, or perfect. Hence, its excellent quality,
whether pasteurized or unpasteurized, was due to the quality of
the raw material used.

Cream of the character mentioned above is not available in the
average creamery. Many investigations have demonstrated
that pasteurization does produce butter of excellent keeping
quality. In addition to this, it entirely eliminates the danger of
transmitting disease to human beings or to animals. Veteri-
narians and scientists seem to be divided in opinion as to whether
bovine tubercle bacilli can be transmitted to human beings,
but the fact that tubercle bacilli have been found in a vigorous
condition in butter has a tendency to create a fear in the minds of
some people that such a danger exists. For this reason alone,
if for no other, cream should be universally pasteurized for butter-
making, especially in creameries where facilities are available
for domg work of this kind. Pasteurization gives the man-
ufacturer better control of the cream so that a more uniform
quality of butter can be manufactured. The wide adoption
of pasteurization in this and other countries, and the fact that

206 PASTEURIZATION

almost every city of any size requires it would seem to indicate
that it should be made compulsory. Since the hand cream sep-
arator has been generally adopted on the farm, pasteurization
seems more necessary than before, as the washing and cleansing
of all dairy utensils, including the separator, is left to the farmers,
and it is only reasonable to suppose that some of them are care-
less. Hence, we can see the necessity for pasteurization from a
hygienic standpoint if from no other.

> <i
Fic. 67.—The Simpiex regenerative Fic. 68.—The Jensen pasteurizer.
pasteurizer (assembled).

Sanitation Must Accompany Pasteurization—The chemical
and bacteriological laboratory of the American Association of
Creamery Butter Manufacturers analyzes, chemically and bac-
teriologically, samples of butter sent in by members. Thousands
of analyses are made during the year. It is found that the butter
that contains the lowest counts of yeasts and molds is invariably
produced in the best creameries. Certain species of bacteria,

SANITATION MUST ACCOMPANY PASTEURIZATION 207

yeasts and molds are present in almost all hand separator cream
and cause the deterioration of butter in storage; the elimination
of these micro-organisms retards such deterioration. Milk or
cream that is efficiently pasteurized will contain neither yeasts
nor molds. In laboratory work conducted by the Association,
butter in which the combined count falls below ten yeasts and
molds in 1 c.c. of butter is considered good; in some of the best
creameries the combined count drops to five or below. There
are Other things that affect the count of yeasts and molds found
in butter. Pasteurization of cream may be perfect, and yet the
cream may pass through unsanitary pipes and again be inocu-
lated with yeasts or molds. Vats, faucets and churns are
sources of contamination. Of the creameries sending butter to
the Association laboratory, those whose butter shows the lowest
count of yeasts and molds are creameries that are noted for
observing extra precaution concerning sanitary methods in con-
nection with all utensils that come in contact with cream. They
use recording thermometers and automatic valves for regulating
temperatures in pasteurization. The first cream passing through
the pasteurizer is returned and reheated. Butter made in the
creameries above-mentioned sells constantly at a premium.
The quality of the cream received by them is no better than that
- received by other creameries operating in the same territory,
which make very inferior butter.

Pasteurization expels from the cream vapors and gases,
especially carbon dioxide gas; it removes volatile substances and
flavors absorbed by the cream or milk. The heating causes the
clusters of fat-globules to break up. Due to uniformity of
quality and pasteurization, Denmark has been able to secure
almost absolute control of the English market. Danish butter
commonly sells at a premium over any other butter finding its
way to.that market, or at least it did prior to the war.

One of the authors in discussing this subject with an English
merchant, who handled a great deal of butter, asked for an
explanation of the preference given to Danish butter. He
answered that they occasionally got better butter from some
other countries but that it did not run uniform in quality. He

208 PASTEURIZATION

said that the Danish butter was mild in flavor and uniform in
quality; in other words, it suited the trade and that was all that
was wanted.

Efficient pasteurization not only enables the manufacturer
to make a more uniform grade of butter, but it makes the butter-
milk safe to feed to live stock, thus preventing the spread of
infectious diseases. It is said by some that if pasteurization were
adopted more skill would be required on the part of the butter-
maker. With valves for controlling the steam pressure and the
use of recording thermometers, uniform pasteurization to any
desired temperature can be brought about by a maker of ordinary
skill, if he applies judgment to the details of his creamery opera-
tion.

Methods of Pasteurization—At the present time there are
three methods of pasteurization employed for butter-making.
The one most generally used is the flash or instantaneous heating
method. Under this method the cream is heated to a high
temperature, 180° or 185° F., and quickly cooled, by passing
over a cooler, to ripening temperature or to churning tempera-
ture, as the case may be. In the vat, or holding, method cream
is usually heated to a temperature of 150° to 160° F., held at
this temperature for twenty to twenty-five minutes, and cooled
to ripening or churning temperature. Some use the combined
flash and holding method.

Some of the best creameries that use the flash method, or high
temperatures, follow what is known as the double system of
pasteurizing. Two pasteurizers are attached to each other;
the cream passes to the first pasteurizer from the forewarmer,
where it is heated to a temperature of about 135° or 140° F. It
passes from the first to the second pasteurizer where it is heated
to 185° F., or any temperature desired. The live steam is con-
nected with the second pasteurizer, and the exhaust steam from
the second pasteurizer furnishes heat for heating the cream in
the first pasteurizer to 140° F., or thereabout. The heating of
the cream in the first pasteurizer increases the fluidity of the
cream. Hence, when it enters the second pasteurizer, the heat
comes in contact with all particles of the cream, and the efficiency

METHODS OF PASTEURIZATION 209

of pasteurization is thereby increased. From general observa-
tion of work in many creameries belonging to the American
Association of Creamery Butter Manufacturers, the authors
feel safe in recommending this system. .

One of the authors first saw this system in general use at the
Experiment Station at Kiel, Germany, something over twenty
years ago. Dr. Weigman was heating to 190° F. at that time,
and claimed very satisfactory results.

The relative merits of the two systems—the vat system where
the heating is done through a coil, or the use of a machine con-
structed exclusively for pasteurizing milk and cream—depend
largely upon local conditions. If the first cost only is taken
into consideration, cream can be pasteurized more cheaply under
the vat system, as the heating and the cooling are done in the
same vat. Ina small creamery where space has to be taken into
consideration, the vat system is to be recommended. Not only
does it require less space but it involves less labor. The objections
to the vat system are, first, that the vat is not constructed for a
pasteurizer, and, second, that the wear and tear (heating and
cooling, and expansion and contraction) will affect the life of
the vat. These are items that must be taken into consideration
when figuring the cost over a period of years. Ina factory where
a large volume of business is transacted, the regular pasteurizer
would be preferable. It is much stronger than the vat and is
constructed exclusively for the purpose of pasteurizing cream.
In addition to this a greater amount of cream can be cared for ina
shorter space of time. The cooling is done much more quickly
where a regular cooler is used. Another advantage is that the
heating and cooling are not done in the same vat, thus avoiding
the expansion and contraction of the metals.

Some use the method of heating in the flash pasteurizer and
cooling ina vat. This does away with the necessity for a cooler,
but, as stated above, the cooling is not done as rapidly as it would
be if a regular cooler were used. This system works well where
the holding system is practiced and lower temperatures are used
for pasteurizing. Cream can be run into the ripening vat irom
the flash pasteurizer, held any desired time and cooled with a coil.

210 PASTEURIZATION

Under the regenerative principle the cold cream is heated
by the hot cream passing from the pasteurizer. In the outflow,
hot cream is cooled by the cold cream flowing into the pas-
teurizer. The hot and cold cream then equalize their respective
temperatures by passing in different directions. It is claimed by
manufacturers of these pasteurizers that they effect a saving of
25 per cent, or more.

Most pasteurizers at the present time are constructed of
heavy copper coated with tin. The heating surface of some of
these pasteurizers is lined with German silver. From the stand-
point of heat conductivity there is little choice between these two
metals. It is a well-known fact that some metals will conduct
heat better than others; the relative heat conductivities of
copper and tin are .g18 and .145 respectively. This means that
copper will conduct heat nearly seven times as fast as tin of the
same thickness, and therefore that copper might be seven times
as thick as tin and still transmit as much heat as the tin. From
this it can be seen that a heating wall made from copper can be
increased slightly in thickness, and thus aid in stability, without
affecting the degree of heat conductivity of the wall very much.
The heating surface must be strong enough to withstand a
slight steam pressure, otherwise the heating wall is likely to
collapse or cave in, in case of slight variation in the steam pressure.
It used to be a rather common occurrence for the heating walls of
the pasteurizer to cave in or collapse in case of a slight variation
in the steam pressure. ‘This does not happen so often now.

The condition of the cream has some bearing on the heating
surface. Sour and coagulated cream burns and adheres to a
greater extent than does sweet cream. This is evidently due to
the lesser fluidity of the sour cream. Where two pasteurizers
are used, this tendency is overcome to a very large extent.

Efficiency of Pasteurizers.—Experiments conducted by Dr.
Storch of the Royal Experiment Station, Copenhagen, Denmark,
show that condensed steam offers great resistance to the trans-
mission of heat. The comparative heat conductivities of water
and copper are .oo16 and .9 respectively, as found by Dr. Storch.
It will thus be seen that copper is 6co times as good a conductor

EFFICIENCY OF PASTEURIZERS PAUL

of heat as water is. This would mean that a quiet layer of water
3 mm. in thickness would offer the same resistance to heat as a
layer of copper 2 meters in thickness. Consequently a very
thin layer of water or condensed steam on the sides of the heating
wall would greatly interfere with the economic efficiency of a
pasteurizer.

In order to overcome this difficulty drip-rings were circled

Fic. 69.—Jensen sanitary pasteurizer-regeneratcr and cooler (Jensen
Creamery Machinery Co.).

round the drum of the pasteurizer, at intervals, on the steam side
of the heating surface. The first rings put around the pas-
teurizer were narrow, smooth bands. These did not give entire
satisfaction, as the condensed water from the top rings would
drip on the edge of the lower ones, and cause the water to spatter
over the side of the heating wall. Another kind of ring was then
invented which was thin, narrow, and provided with tceth like

212 PASTEURIZATION

those of a saw. The rings were fastened to the heating-wall at
proper intervals at an angle of 45°. The rings were so arranged
that the drops of condensed water escaping from the end of each
saw-tooth would fall in the hollow between the teeth in the lower
rings and thus prevent any spattering of the water against the
heating wall. These contrivances greatly increased. the eff-

oe ‘ z . ee
ARRON -

Fic. 70.—Elyria pasteurizer (Elyria Enameled Products Co.).

ciency—as much as 48 per cent—and the capacity of the pas-
teurizer experimented with.

Cost of Pasteurization.—Dr. Storch in his forty-third report
at the Royal Experiment Station at Copenhagen, Denmark,
reported that it required 80 pounds of steam to heat tooo Danish
pounds of milk from 4o° C. to 85° C. This would be equivalent

COST OF PASTEURIZATION 213

under American conditions to about 90 pounds of steam to pas-
teurize 1000 pounds of milk from go° F. to 185° F.

According to good authorities, it takes about 1 pound of lump
coal to produce 6 pounds of steam, although much depends upon
the fireman and the construction of the boiler. Based upon
this estimate, it would take 15 pounds of coal to produce go
pounds of steam. If the coal cost $4.00 per ton, the cost of
the 15 pounds would be 3 cents. If the milk tested 3.6 per cent
fat, the calculation upon one-sixth overrun of 1000 pounds of
milk would produce 42 pounds of butter. The cost of pasteuriz-
ing the milk producing 42 pounds of butter would then be 3
cents, and the cost of pasteurization per pound of butter would be
.o7 of a cent.

The figures submitted by Storch, however, were obtained a
number of years ago, and cannot be applied to conditions in this
country at the present time.

Mortensen, who has given a good deal of thought to the cost
under the continuous and vat methods, estimates as follows:

ont mous Vat Method,
Method, ave
Cents
(Costole steam Meetaw epee cfeieas Sst ise Bhe ie, Hees eter .O19 .o16
COStiOMwaAter im Wate ak Stes tite tes chersla: seco Sad aen 009 O21
Cost of labor and equipment...................... . 181 .054
otal Mea pay Oh UAT ei NAM STM b oon. meen aes . 209 .OOT

The cost in different factories would vary with the cost of fuel.
With the high railroad rates prevailing at the present time
and the high price of labor, we can estimate the cost at about
one-fifth of a cent per pound.

In addition to this, the loss of fat in buttermilk seems to be a
trifle more in pasteurized than in unpasteurized cream. This
may be due to the precipitation of the casein by heat. Pas-
teurization is necessary from a hygienic standpoint. It gives a
guarantee to the consuming public that all pathogenic bacteria

214 PASTEURIZATION

are destroyed. It takes away from the enemies of butter the
opportunity of proclaiming that disease may be transmitted to
the human family through this article of diet. There is less
danger of transmitting disease through butter than through any
other dairy product.

The senior author has been for more than thirty years engaged
in the butter business in various capacities, from manufacturer to
conductor of investigational work, and has never known of a
case where any disease was transmitted through butter, from
either pasteurized or raw cream. It has been demonstrated in
all parts of the world that raw or unpasteurized milk will transmit
bacillus typhosus. The first epidemic of typhoid fever which
was traced to infected milk was one occurring at Penrith in
1858 (Taylor). Since that time cases have become so numerous
that almost all municipalities insist upon efficient pasteurization
of milk.

In addition to the effect that pasteurization may have on
butter, pasteurization of the skim-milk and cream puts both the
skim-milk and buttermilk in a condition where there is no danger
of transmitting disease to animals.

Disadvantages of Pasteurization.—The disadvantages of pas-
teurization are, first, the cost of installing equipment, and, second,
the additional cost of operation. Due to the increased cost of
labor in recent years, it is difficult accurately to estimate the cost.

Advantages of Pasteurization—The advantages of pas-
teurization far outweigh the disadvantages, and may be sum-
marized as follows:

(1) It destroys pathogenic bacteria if there be any present
in milk and cream, and renders them and their products and by-
products perfectly safe as foods.

(2) It destroys practically all germ life and enables the butter-
maker to produce a more uniform quality of butter.

(3) It is one of the large factors which improve the keeping
quality of butter.

(4) It eliminates some of the taints in cream.

CHAPTER XVI

CREAM-RIPENING AND STARTERS

CREAM-RIPENING

Definition.—By cream-ripening we mean the treatment
cream receives from the time it is put into the ripening-vat until
it is put into the churn; and also the chemical, biological, and
physical changes it undergoes during this time.

In the whole-milk creameries and in a few of the creameries
receiving only cream, the cream goes into the ripening vat in the
morning and no more is added during the day. In most cream-
eries, however, cream is taken in throughout the day. This
system does not permit of such perfect ripening of the cream;
besides, it necessitates opening and closing the vat at intervals.
Under this latter system it is important that the cream vat have a
fly screen over it, and that one end of it be covered with a cream
strainer through which all cream is strained before it enters the
vat.

Objects of Ripening. To Produce Flavor and Aroma.—
The chief object of cream-ripening is to secure the desirable
and delicate flavor and aroma which are so characteristic of good
butter. The necessary flavoring substances, so far as known,
can only be produced by a process of fermentation. Good butter
possesses two characteristic flavors. One is known as palate
flavor, or the distinctive butter flavor. ‘The other is what is
described by butter judges as a nose flavor or aroma, sometimes
described as “ bouquet” flavor. While the flavor and aroma
characteristic of good, properly ripened cream and the butter
made from it are produced by fermentation, the chemical changes
that produce them are not well understood. It is claimed by
some that the palate flavor is derived from the volatile fatty

215

216 CREAM-RIPENING AND STARTERS

acids, and the aroma from a fermentation of the milk-sugar.
Good cream must possess a clean, pleasant, acid taste. For this
reason, it is essential to have the acid-producing germs predom-
inate during cream-ripening.

Butter has been made from sour cream from time immemorial.
Housewives discovered a great many years ago that butter made
from ripened cream had a more pronounced flavor and aroma
than butter made from unripened cream. They also found
that cream properly ripened would churn more easily and give a

Fic. 71.—Projzress vat pasteurizer and cream-ripener. (Davis-Watkins
Da‘rymens Mfg. Co.)

more exhaustive churning; hence, the practice of souring cream
has been handed down to the creameries from the home dairies.
Some women hecame noted for making butter of an exceptionally
fine quality, because, in addition to observing cleanliness as the
first requisite in making good butter, they selected nice, clean-
flavored milk and let it sour naturally; this was added to the
cream for the purpose of hastening the souring or ripening.
Some of these dairies produced butter which was not only of good
quality but also possessed good keeping qualities.

In the early days of butter-making it was customary for some
to pack their butter in glazed crocks during the latter part of May

CREAM-RIPENING 2G

or the first part of June, cover it with salt and hold it until the
winter months, keeping it in the cellar or some other cool place
until it was used up. As dairying advanced and butter began
to be made on a large scale in creameries, in various countries,
the bacteriologist resorted to the method of isolating certain
species of bacteria for the purpose of ripening cream and pro-
ducing the desired flavor.

It has not yet been proved that any particular species of
bacteria is responsible for the production of fine flavor in butter.
It is generally agreed that the flavoring substances developed
during the ripening of cream are decomposition products of bac-

—

Fic. 72.—Wizard vat pasteurizer and cream-r.pener. (Creamery Package
Mfg. Co.)

terial growth, and it has been generally recognized that the types
producing the lactic acid are the most desirable ones to have
present in cream. ‘There are a great many bacteria in milk and
cream which produce acid, over one hundred species have been
studied and described. It is apparent, however, that only a
comparatively few of these produce the best results in cream-
ripening. Hence, in the preparation of a natural starter, great
care should be exercised in selecting milk that will sour with a
pleasant acid taste.

At the lowa Experiment Station, McKay and Eckles con-
ducted a series of tests on fermentation by taking milk from
different patrons’ herds, placing it in sterile glass bottles and
allowing it to sour naturally. It was found that milk which

218 CREAM-RIPENING AND STARTERS

began to whey off at the bottom of the jar, soon after coagula-
tion, due to certain species of bacteria decomposing the casein,
invariably possessed an undesirable flavor. Samples of milk
which would remain coagulated for some time and whey off at
the top possessed a pleasant acid flavor. By selecting such
samples of milk for: preparing natural starters, these investi-
gators were able to produce starters that gave excellent results
in cream-ripening.

Butter made at the school that scored the highest at one of
the large national conventions, receiving a score of 98, was made
from cream that had been ripened by a natural starter. The
whole milk, received at the creamery when two days old, was
skimmed so as to contain a very high per cent of milk-fat. The
object was to concentrate the fat and get rid of as much of the
skim-milk with its undesirable bacteria as possible, and then
dilute the cream with fresh milk from the herds whose milk
showed desirable results when souring naturally. The addition
of a starter ripened naturally from the above-mentioned milk,
ripened the cream which produced the high-scoring butter.

Another test was made in a national contest where dif-
ferent parties were placed in charge of the ripening, taking the
entire milk as it came in on four different days, and the same
method was followed with correspondingly favorable results.
Tn this contest, in which about eight hundred creameries com-
peted, the butter made by this method, on these four different
days scored the highest, third, fourth and fifth in flavor. This is
a further substantiation of what has been reported by various
investigators, Storch, Conn and others, that the flavor developed
depends very largely upon the species of germ life that predom-
inate.

Where cream has been pasteurized and inoculated with a
starter containing the right organisms, the effects of the starter
will be more pronounced than if the cream were manufactured
raw or unpasteurized. This is due to the fact that the promis-
cuous assortment of organisms in the natural bacterial flora is
largely destroyed by the heating process in pasteurization. Bac-
teriologists do not agree as to what species of bacteria is respon-

CREAM-RIPENING 219

sible for the high flavor and aroma of butter. Conn claims that
the germs which act upon the nitrogenous matter of milk are
associated with the lactic-acid-producing bacteria in the pro-
duction of desirable butter flavors. Weigman asserts that
the best results are obtained when a variety of species work
together in the cream. He has isolated a single species of germ
which produces alcohol and lactic acid as by-products, and which
according to experimental evidence deduced by him, is capable
of producing the delicate butter flavors. Freudenreich also
studied a species of germ which produced alcohol and lactic acid
as by-products, and which he claimed was able to produce the

Fic. 73.—Cherry vat pasteurizer and cream-ripener. (J. G. Cherry Co.)

characteristic butter flavors. LEckles studied the question of
flavor production during cream-ripening. He came to the con-
clusion that the flavor and aroma substances developed during
cream-ripening may be produced by a variety of acid-producing
bacteria. He asserts that of the species tried the most common
-milk-souring organism (Bacterium lactarii) gave the most satis-
factory results as a culture for ripening cream. Storch, who has
perhaps studied this question to as great an extent 2s any of the
investigators, maintains that the germs producing lactic acid are
essential to good cream-ripening, and that the flavor and aroma
products are the results of the joint action of a great many
species of lactic-acid-producing germs. Tiemann finds that an
addition of a small amount of hydrochloric acid to the cream does

220 CREAM-RIPENING AND STARTERS

not produce the characteristic flavor, and indicates that the
process of fermentation is necessary to secure the proper flavors.

The study, by Hammer and Bailey of the Iowa Station, of the
causes of flavor and aroma development in cream-ripening is
briefly outlined in the section of this chapter on “ Starters.”

Fic. 74.—Vertical universal ripener and pasteurizer. (Jensen Creamery
Machinery Co.)

This is probably the fullest investigation of this subject—in
America at least—that has been conducted in recent years.
Ripening Temperature of Cream.—In regular practice the
ripening temperature of cream usually ranges between 60° and
75°F. The lactic acid organisms and those associated with them

CREAM RIPENING Papal

in a good starter have the greatest relative growth at 70° F., or a
little above. Generally speaking, it is advisable to adopt a little
lower ripening temperature in summer than in winter, For one
thing, the cream has a tendency to rise a little in temperature in
summer and to fall a Jittle in winter, during the time of ripening;
and furthermore, the natural bacterial flora present in summer are
more favorable to cream-ripening than those present in winter.
With the necessary modifications to meet conditions, 65° to 70°
will be found a suitable range of temperature to adopt during the
summer season and 70° to 74° during the fall and winter months.
The amount of starter used and the length of the ripening period
are factors that must be considered in deciding upon the tem-
perature to be used. Where a fairly high ripening temperature
is adopted a little greater precaution must be taken to prevent
over-ripening of the cream, particularly if a liberal amount of a
good, active starter be used.

Amount of Starter to Add to Cream.—The amount of starter
to add, the ripening temperature and the length of the ripening
period are related factors that influence each other. Also the
richness of the cream places a limit upon the amount of starter
that can be used. Generally speaking, where the separating is
done on the farm the richness of a vat of cream is not so great as
where the milk is delivered to and separated at the creamery,
and consequently it is not practicable to use so high a per cent
of starter in the former as in the latter case. The quantity of
starter used will range from 1c to 20 per cent, depending upon the
ripening temperature adopted, the richness of the cream, the time
within which the ripening is to be done, and, to some extent, the
cost of the milk or skim-milk used in making the starter.

Mixing the Starter with the Cream.—When the starter is
added to a vat of cream the coils should be run for a few
minutes in order to mix the two very thoroughly. This is
necessary to insure uniformity of ripening.

Tests for Acidity —The acid in cream is developed in the milk-
serum, and the per cent of butter-fat that cream contains merely
takes up space. Hence, in ripening cream some consideration
should be given to the per cent of fat in it, as the fat is a neutral

222 CREAM-RIPENING AND STARTERS

quantity. For instance, it is not safe to develop as high a per
cent of acid in cream containing 40 per cent as could be devel-
oped in cream containing 25 or 30 per cent of fat. For this and
other reasons it is advisable to use a special test with which to
measure the amount of acid developed in the cream. There are
two acid tests in general use now in creameries, viz., ‘‘ Mann’s
Test ” and the “ Farrington Test.”

Mann’s Test.—Mann’s test consists of measuring the acid in

Fic. 75.—A creamery equipped with glass enameled tanks and vats.

the cream by means of an alkali of a definite strength. The kind
of alkali used is usually a tenth normal solution of caustic potash
(KOH) or caustic soda (NaOH). These solutions can be made
up very cheaply or bought from the supply houses. Mann’s
test is based upon measuring out 50 c.c. of cream by means of a
pipette. While the test is based on 50 c.c. of cream a 25 c.c.
pipette can be used, and the reading multiplied by two, thus
avoiding the necessity of using so much cream. Even a smaller
pipette could be used, but 25 c.c. is preferable to a stnaller quan-
tity, which would increase the danger of error. A few drops of an

CREAM-RIPENING 223

indicator (phenolphthalein) are added. This indicator gives a
red color in an alkaline solution, and no color in an acid solution.
The tenth normal alkali solution is poured into a burette, and
allowed to run into the 50 c.c. or 25 c.c. of cream (which is kept
stirred thoroughly) until it begins to
turn pink in color. At this point it is
neutral. The number of cubic centi-
meters of alkali required to neutralize
the acid in so c.c. of cream indicates the
number of degrees of acid. For in-
stance, if it should require 32 c.c. of a
tenth normal alkali to neutralize the acid
in 50 c.c. of cream, the acidity of the
cream would be 32°. (1 c.c. of N/1o
alkali=1° Mann’s Test.)

Mann’s test reading can be con-
verted so as to express the results in
percentage similar to the Farrington -—(\—geqam@Mla
test. As) rc.) of; the tenth nonmnal 5. A
alkali neutralizes .cog gram of pure lactic | Mann’sac'd test. Instead
acid, 32 c.c., as in the above case, would of the burette the alkati

é ° can be kept in a large
neutralize 32 times .cog. This would Eettichais homey Tee
give the amount of acid, calculated in 7 and 78.
terms of lactic acid, present in the 50 c.c.
of cream. This product divided by the 50, and multiplied by
100, would give the percentage of the acid present.

Farrington Test.—The same principle is involved in the Far-
rington test. The alkali is put up in small tablets, already
containing the indicator. These tablets contain a definite
amount of alkali, and are represented as retaining their strength.
They lose it, however, if they are exposed to the atmosphere. The
amount of alkali in each tablet is such that when five of them are
put into a graduated cylinder, the cylinder filled up with dis-
tilled water to the 97 c.c. mark, and the tablets thoroughly
dissolved in it, a solution is obtained, each cubic centimeter of
which represents .or of 1 per cent of acid, provided 17.6 c.c. of
cream are taken. The tablets can be made up of different

224 CREAM-RIPENING AND STARTERS

strengths for the use of different-sized pipettes, but as the 17.6
c.c. pipette is the one which is used in the ordinary Babcock test,
directions are given for the use of this pipette only. For a
more detailed description of the acid tests see “‘ Testing Milk and
its Products,” by Farrington and Woll.
Degree of Acidity that Cream Should be Ripened to.—As to

Fic. 77.—Arrangement for keep- Fic. 78.
ing alkali for the Mann’s test.

the per cent of acid that should be developed in cream, this will
depend upon such factors as the richness of the cream, the market
demands as to fullness of flavor in the butter, whether the cream
is sweet cream or cream that has previously soured and been
neutralized, and the length of time the butter is likely to be held
in storage.

STARTERS 225

As has already been pointed out, rich cream should not show
as high a per cent of acid when ripened as cream with a lower
fat-content. If it should do so it is really a riper cream, that is,
the skim-milk portion of it has been ripened to a higher degree
of acidity.

Where cream has soured and been neutralized before pas-
teurization, it is advisable not to ripen to as high a degree of
acidity as might be developed were the cream sweet to begin

ERINON NOREEN

Fic. 79.—Apparatus for the Farrington acid test.

with. Especially does this apply when butter is ee to be held
any length of time.

Unless market conditions demand it—and it is only in very
exceptional cases that they do—it is not advisable to ripen
average cream, or cream with a fat-content of about 30 per cent
to an acidity of over .50 to .55 per cent. It is safer to err a trifle
on the side of underripening rather than to overripen cream.

STARTERS

Definition.—By the term starter, in cream-ripening, we
understand a medium containing a preponderance of desirable
germs present in a vigorous condition.

226 CREAM-RIPENING AND STARTERS

History.—The use of starters in the dairy industry dates
back a great many years. The fact that starters helped in the
manufacture of dairy products was recognized years ago by
practical men even before scientists recommended the use of
pure cultures. In European dairy countries the use of the
buttermilk borrowed from a neighboring factory to add to the
cream in order to overcome abnormal conditions, was a common
occurrence. In Holland, sour whey borrowed from some other
factory was used to overcome gassy fermentation in cheese-
making. While the reasons for this were not well understood,
the underlying principle involved was that of overcoming the
undesirable fermentation by adding ferments of an antagonistic
kind.

The introduction of commercial starters for cream-ripening
dates back to 1890, when Professor Storch recommended their
use in creameries in Denmark. After commercial starters had
been used long enough in that country to demonstrate their
worth, they were introduced into this as well as practically all
the European countries, and are now used quite extensively.

Classification of Starters.—Generally speaking, the different
kinds of starters are included under the names (1) Natural,
and (2) Commercial. The latter are prepared from a culture
of bacteria obtained from the laboratory. The former, or nat-
ural, include a great many kinds of dairy products which
are supposed to contain a preponderance of those germs which
are involved in the production of desirable flavors in butter.
Buttermilk, sour cream, whey, and sour whole or skim-milk,
are classed under this heading. While all these may be termed
natural starters, and at certain times the use of any one of them
may produce better results than if no starter at all were used,
it is not safe to rely upon them to bring about better results
than could be obtained without the use of starters, because these
products are likely to be contaminated in a large degree with
undesirable germs.

Preparation of Natural Starters.—The best natural starter
is usually obtained by selecting a number of different samples
of the best milk coming into the creamery and putting them

STARTERS oth

into cleaned sterile glass jars. The samples are allowed to stand
until sour at about 70° F. The sample which coagulates into a
smooth uniform curd, and has a pleasant acid taste and smell is
selected and used as a mother-starter. When a large quantity
of selected pasteurized milk or skim-milk is inoculated with this
and cooled to and held at a temperature of about 70° F., until it
begins to coagulate, it will usually prove to be a starter which is
equal, and often superior, to a commercial starter.

Commercial Starters or Cultures.—Experiments have amply
proved that certain species of bacteria are chiefly responsible
for the butter flavors developed in cream during ripening. This
fact has given rise to the use of cultures prepared in a commercial
way. ‘These cultures contain, in a vigorous condition, the germs
which produce the desirable flavors and aroma. The cultures
are put up in laboratories specially provided for this kind of work.
Some of the laboratories put these cultures up in liquid form
while others put them up in a dry or powder form. The liquid
starters consist of a sterile nutrient medium, milk or beef broth,
inoculated with the culture; while the starters in dry or powder
form are prepared by mixing the liquid culture with some suit-
able substance, such as milk-sugar, and drying this mixture at a
temperature low enough not to injure the germs present in it.
The cultures that are put up in the liquid form will not keep so
long, and it is not safe to use them after they are about nine days
old. The cultures which are put up in powder form have the
advantage that they can be kept for a much longer time and still
retain their vitality. Both kinds as a rule are good while they
are fresh. We give a list on next page of the commercial cultures
with which the authors are familiar.

Technically speaking, most of the commercial cultures sent
out from the different laboratories, to be used in the preparation
of starters for milk- and cream-ripening, are not pure cultures of
lactic acid organisms, although they are commonly spoken of as
such. A pure culture is one which contains just a single species
of organism, and most of these cultures contain more than one.
The commercial cultures are, however, limited as to variety of
species contained—usually two and at most three—and do not

228 CREAM-RIPENING AND STARTERS

contain a promiscuous variety of organisms. It is for this
reason that they are commonly designated as pure cultures.

S. C. Keith, Lactic Acid Culture
Charlestown, | Duplex Culture Liquid
Mass. Boston Butter Culture
O. Douglas, Boston Butter Culture
Boston, Duplex Culture | Liquid
Mass. Lactic Acid Culture
Ameri- OSs, Ericsson’s Butter Cul- uote
iy St. Paul, ae and
Minn. Powder
Chr. Hansen’s Lab-
oratory, Little | Lactic Ferment Powder
Commercial ass Sleyts
eee ce Parke, Davis & Co., This culture is put
Detroit, Flavorone | up in tablet and
| Mich. " capsule forms
Blauenfeldt &
3 Danish Lactic
Tvede, Copen- | | Powder
Acid Ferment
hagen, Den.
Hjort & Fog’s
Foreign Laboratory Cul. Lactic
Copenhagen,
Den.
S. P. Storm,
Tillitze, Naks- | Starter
kov, Den.

Extensive work done by Hammer and Bailey of the lowa
Station not only supports what has just been said regarding
commercial cultures, but also goes to prove that while the
organism which predominates in a good culture or starter is the
common lactic acid organism (Streptococcus lacticus), there
must also be associated with this, an organism or organisms,
which will develop volatile flavor and aroma-producing acids.
Hammer says that it seems that there is no longer any question
that starters are mixed cultures, and that even a pure lactic
acid culture sent out from a laboratory very soon becomes a
mixed culture containing volatile acid-producing organisms.
These findings by Hammer and Bailey are supported by the work
done by Storch in Denmark, and Beckout and Ott de Vries in
Holland.

STARTERS 229

According to Hammer, the lactic acid, which is non-volatile,
produces an acid flavor but very little of the flavor and aroma so
characteristic of a good, well-ripened cream and the butter made
from it. The organisms which he has found to be the most
suitable associate organisms of the lactic acid organism (Strep-
tococcus lacticus) are Streptococcus citrovorus and Streptococcus
paracitrovorus. S. citrovorus acts upon the citric acid of milk
and cream (hence its name), and also to a certain extent upon the
lactic acid, and converts these into volatile, flavor- and aroma-
producing acids. S. paracitrovorus, in addition to performing
the same function, also develops and uses another product.

A good starter is one which will develop a fair proportion of
the volatile, flavor- and aroma-producing acids without the
development of an excess of acidity; that is, it will afford all the
advantages to be gained from the proper ripening of cream without
the disadvantages that come from ripening it to too high a degree
of acidity. The great problem is that of the maintenance of a
proper balance between the lactic acid organism (S. Jacticus) and
the associate organism or organisms which develop the volatile,
flavor- and aroma-producing acids. One of the large factors in
maintaining this balance is a proper ripening temperature in
both starter- and cream-ripening. Hammer mentions 70-72° F.
as a very favorable range. A temperature much above this is
more favorable to S. lacticus than to S. citrovorus, that is, it will
enhance the development of lactic acid to a greater extent than
that of the flavor- and aroma-producing acids, and throw the
ripening out of balance.

It would seem then that the big problem for our laboratories,
in the preparation of commercial cultures, is to supply a culture
which, if properly handled in the creamery, will develop a reason-
able amount of suitable, volatile flavor- and aroma-producing
acids without the development of excessive acidity in the cream;
and that one of the large problems for the creameryman is proper
temperature control in both starter and cream-ripening, so as to
enable flavor production to keep pace with lactic acid produc-
tion. It would seem to be quite a safe practice to ripen the
cream at a temperature of 70° F., provided care is taken to cool

230 CREAM-RIPENING AND STARTERS

it early enough to prevent the development of acidity from going
too far. Under the varying conditions that exist in the dif-
ferent creameries each creameryman will have to decide for
himself the temperatures that best suit his conditions. What
the authors have aimed to do is to state the underlying prin-
ciples of successful starter and cream-ripening, and what they
would urge most is the intelligent application of these prin-
ciples.

Preparation of Commercial Starters.—All of the starters
mentioned above have been tested and are known to produce
good results. The first step in the preparation of a mother-
starter (starterline) is to prepare preferably a glass jar or bottle
by thoroughly cleaning and sterilizing it. Glass jars are used in
preference to any other vessel, because if they are unclean in any
way, it will be apparent. Secondly, there are no seams and no
places on the inside which will corrode, and in that way retain
unnoticeable dirt; and in the third place, the nature of the coag-
ulation can be readily observed through the glass. Mason jars
and sampling bottles are suitable. The kind of bottle which
is used for marketing milk gives very good results.

The second step consists in selecting suitable milk. The
milk must be in as pure and sweet a condition as possible. A
good starter can be produced from either whole or skim-milk.
At one time skim-milk was given a decided preference for use in
the making of starters. But the views of some of our leading
bacteriologists and practical creamerymen, experienced in the
preparation and use of starters, have changed upon this point
and they now express a decided preference for the use of whole
milk starters. The reasons for this preference may be briefly
stated: The whole milk is generally more easily selected; it
is the practice in some of our best creameries to have some
farmer supply milk, produced under special sanitary conditions
and cooled promptly to a low temperature, for starter purposes.
The trouble of separating and a possible extra source of contam-
ination are avoided. The presence of the fat in the milk serves
two useful purposes; first, the cream that rises seals the starter
over and prevents contamination, and second, the exclusion of

STARTERS 231

air prevents the development of certain injurious organisms,
which may be present and which require air for growth.

However, fine starters can be made from either whole milk or
skim-milk, and the point of first importance is that the milk
used be sweet and in a clean, sanitary condition.

The milk which has been selected for the mother-starter, or
starterline, is then pasteur-
ized. The pasteurization is
best accomplished by the
intermittent method. If
considerable milk is to be
pasteurized it is best to
make use of a clean, steril-
ized starter can. If only a
small portion is to be pas-
teurized, just enough for the
mother-starter, the milk can
be put directly into the jars.
The jar half full is about the
proper amount of milk to
use. The directions sent
with some pure cultures
recommend as much as half Nears

Fic. 80.—An Incubating Chamber for
a gallon or a whole gallon Starters. The inner compartment will
of milk. As a rule better hold a pail of water and the bottles for

results are obtained if only the mother-starters. The temperature

9 : can be kept at any desired point by the
about a pint of milk is use of warm or cold water. The four-
taken. If the milk for the inch space between the walls is filled with

mother-starter is pasteur- hay or mineral wool. (Dairy Bac-
edie dhe glass bottles teriology, Russell and Hastings.)

or jars, it is advisable to set the bottles containing the milk
into cold water,—covering the jar so as to prevent outside con-
tamination,—and then heat up the water gradually. Care
should be taken not to insert these bottles suddenly into scalding
hot water, or to let the steam strike them, for either is likely to
crack the bottles. Care should be taken also to exclude water
from milk used for starters. It is advisable to heat this milk, for

232 CREAM-RIPENING AND STARTERS

the starterline, as high as possible in hot water, say up to about
200° F. The sample may assume a cooked taste, but this will
soon disappear after the starter has been carried on a few
days. The milk should be left at this high temperature for
about ten or fifteen minutes. A longer time does no harm.
Then the milk is gradually cooled to about 80° F. This high
temperature is desirable, because the germs present in the
commercial culture may be somewhat dormant. This high
temperature would tend to revive them more quickly than a
lower temperature. Great care should always be taken to
cool the milk previous to inoculating it with the pure culture,
otherwise the germs present in the culture will be destroyed.
Inoculation.—The next step is to inoculate the prepared
milk with the culture obtained from the laboratory. The
bottle which contains the culture is carefully opened, turned
over and emptied into the pasteurized milk. It should be
held down closely to the mouth of the jar containing the
sterile milk, in order to prevent, as far as possible, the entrance
of the air and the consequent danger of contamination. Then
the milk containing the culture is thoroughly stirred and set
away in a room where the temperature is about 7o° F. This
will gradually cool the milk from 80° to 70° F., and in about
twenty to forty hours the milk will sour and coagulate. Germs
in nearly all of the liquid cultures are rather slow in acting upon
the milk, undoubtedly due to the dormancy of the germs, and toa
comparatively few of them being present in the culture. When
the powdered cultures are used, a little more care is essential to
get the powder thoroughly mingled with the milk. It is a trifle
more difficult to get the powder thoroughly mixed with the milk
than it is to get the liquid cultures mixed. If anything is used
with which to stir the sample, it should be sterilized before com-
ing in contact with the milk. This applies in the preparation of
all cultures. In testing or sampling the mother-starter, nothing
should be allowed to come in contact with it unless it has pre-
viously been thoroughly sterilized. The powder cultures are
usually more vigorous in their effect than most of the liquid
cultures now on the market. The powder cultures usually

STARTERS 233

coagulate the sample in about twenty-four hours, and if the
operator is used to handling the liquid cultures, he should watch
the mother-starters prepared from powder cultures, so that they
do not get overripe. It is very essential that this should not
happen. The time when the germs are most numerous and
most active in the starter is about the time when the sample
coagulates. As soon as this stage has been reached, or just
previous to coagulation, the starter should be cooled down
to at least 50° F., or lower if possible. This prevents any
further growth of germs and the sample can thus be kept a short
time without injury.

Directions usually accompany each of the cultures, but the
above will be found to produce good results with all of those
mentioned in the above list.

By putting from 2 per cent to 5 per cent or more of the
mother-starter into a large sample of pasteurized milk, any
desired amount of starter can be prepared. Im selecting this
amount of milk, as much care as possible should be taken in
order to select the best kind of milk, and keep it from being con-
taminated. When this large sample of starter is at the proper
stage of coagulation, it should be used at once, or else cooled
down to about 50° F. The amount of mother-starter with
which to inoculate the large sample of starter may vary a little
without any bad effects. If the large sample of starter is to
be ready for use in a short time, a larger portion of the mother-
starter can be used for inoculation. If the temperature at
which the starter is set and the amount of mother-starter used
for inoculation are the same from day to day, the starter will
be ripe at nearly the same hour every day, and, consequently,
more uniform ripening results can be obtained. The noticeable
coagulation of the starter when milk or skim-milk is used will
usually take place when there is about .6 per cent of acidity.
A slight coagulation will take place when there is about .5 per
cent of acidity, but it is hardly noticeable. The coagulation-
point may vary with different samples of milk.

If a mother-starter is to be kept any length of time it should
be inoculated into a sample of good fresh pasteurized milk about

234. CREAM-RIPENING AND STARTERS

every other day. If a mother-starter, or starter of any kind,
is allowed to stand too long at a low temperature, the desirable
germs will become dormant, and some undesirable germs will
gradually gain a foothold. . It is a good plan to carry any mother-
starter along for two or three days before it is used to inoculate
a large sample of milk. When the mother-starter is first pre-
pared it sometimes possesses an undesirable taste and smell from
the medium in which the germs were put up at the laboratory.
This smell and taste are eliminated by carrying it on two or
three days previous to its use.

After inoculation and the proper mixing of the mother-
culture with it, a new starter should not be disturbed during
the ripening process. A good starter, when ready for use, will
have a soft, close coagulation, without any gas openings or
wheying off (particularly at the bottom); it will, when mixed,
break up readily and form a smooth, creamy liquid entirely free
of lumps, and will possess a pleasant acid taste and a character-
istic aroma that is delicate and agreeable.

It is of vital importance that a starter be prepared and kept
in specially sanitary surroundings. While not absolutely essen-
tial, it is advisable, if possible, to have a small room, suitably
constructed and equipped, as a starter room. ‘The chief equip-
ment of such a room would consist of,

(x) Quart sealers or bottles in which to prepare the mother-
culture from day to day.

(2) A small galvanized iron tank or box in which to sterilize
bottles, thermometers, dippers, etc. It should have water
and steam connections.

(3) Asmall incubating chamber in which to keep the mother-
starters. This is a small insulated box or chamber lined with
galvanized iron and well insulated so that the temperature
can be kept at any point desired.

(4) A suitable starter can, one of suitable size, in which
heating and cooling can be accomplished readily, and which is
well insulated so as to hold temperature.

One of our largest creamery companies, a company whose
butter has won an enviable reputation in the New York and other

STARTERS 235

eastern markets, follows a system of handling and ripening
cream, in all of its creameries, which is worthy of consideration.
The acidity of the cream is reduced to about 15° Mann’s Test
(.27 per cent) for pasteurization, milk of lime being the neu-
tralizer used. ‘The cream is then pasteurized at a high tem-
perature, 180° to 185° F., after which it is promptly cooled to
ripening temperature. Before adding the starter the acidity
is further reduced to 5° to 8°, Mann’s (.o9 to .14 per cent),
if it has not already fallen to this during pasteurization. If
there be any probability of trouble with metallic flavor the
acidity is reduced still lower—to 2° or 3°, Mann’s test (.04 or
.05 per cent). A carefully prepared starter, which is active
and possesses a desirable, clean flavor, is then added, and the
cream is ripened and held overnight. The aim, in ripening
the cream, is to develop an acidity of about 30° Mann’s (.50 to
.55 per cent) for churning.

Great care is exercised in connection with the raw material
and the preparation and use of the starter, and equal care is
taken to avoid subsequent contamination of the cream, due to
faulty or unclean pipes or utensils. As to the raw material for
the starter, the practice is to arrange with some farmer to
supply milk produced under special sanitary conditions, and
promptly cooled and held at a low temperature until shipped. A
special room is fitted up as a starter-room and this is placed in
the charge of a man skilled in the preparation and use of starters.

The butter made from cream, handled and ripened as indi-
cated, possesses not only a fine, full flavor and aroma when
made, but good keeping qualities as well. The butter made
by this company commonly sells at a substantial premium over
Extras and Specials.

Milk Powder for Starters.—According to experiments con-
ducted at the South Dakota Experiment Station, Bul. 123,
milk powder solutions may be successfully used instead of the
natural milk for starters.

In many large central creameries, skim-milk is difficult to ob-
tain. In such places milk powder can be and is successfully used.

Milk powder is of about the same consistency as flour and

236 CREAM-RIPENING AND STARTERS

dissolves in cold water with similar difficulty. To make the
milk powder dissolve as quickly as possible, weigh out the
required amount of water into the starter can. Turn the steam
on and heat. While the water is heating weigh out the required
amount of milk powder. Use powder at the rate of 3 ounces to
1 quart of water. Add the milk powder to the water and stir
violently. If little lumps remain stir every five or ten minutes
during heating. Continue to heat or pasteurize as though it
were normal milk. The remainder of the processes involved
in making this into a starter are the same as already described.

Length of Time a Starter Can be Carried.—In this country,
even if special precautions are taken, it seems almost impossible
to carry on a starter for more than four weeks without having
undesirable ferments enter. The length of time a starter can be
carried undoubtedly depends upon conditions, and the care
with which it has been handled. When a starter is properly
prepared, cooled gradually before coagulation, and not over-
ripened, it will contain a smooth soft curd, and retain its mild
acid flavor for. at least a month The Danes, who use starters in
butter-making more regularly than any other people, are able to
carry a starter along for six months or more without renewing it.

It is a good plan to keep at least two different kinds of starter
by carrying them on from day to day in small quart jars. Then if
one should happen to “ go off,” the other one can be used instead.

Poor Starters.—Many unsuccessful results from the use of
starters for cream-ripening have been reported. The failure
can be traced to the improper use of starters. If starters are
good they will never bring about poorer results than are obtained
without the use of them. Owing to the fact that it is difficult
to keep the same starter in a good condition very long, many
starters are used which develop abnormal fermentations in cream.
A slightly acid, somewhat bitter taste, and a slimy condition of
the starter are defects which are very common. ‘These condi-
tions seem to be brought about chiefly by overripening it at a
high temperature, and keeping it a long time at a low tempera-
ture before using it. Slimy fermentation is very common in
starters which have been carried on for a time. Whenever this

STARTERS 2a

slimy ferment develops in the starter it can be noticed both in
the cream and in the starter by the failure of the acid to develop
so rapidly as when the proper acid-producing ferment is present.
It seems almost impossible to develop any more than about .5
per cent of acidity in 30 per cent cream, while if the proper fer-
ment were present, about .7 per cent could be developed. A
decrease in the quality of butter accompanies the development
of this ferment in the cream.

Whenever it is found that a starter is not in good condition,
it should not be used, as a poor starter is worse than none at all.
The buttermilk from the previous cream can sometimes be used
advantageously until a new starter can be prepared.

Underripening and Overripening of Starters.—The effect of
Overripening starters has already been mentioned under the
“Preparation of Mother-starters.” The question of under-
ripening starters is also of importance. It is a well-known fact
that just about the time when the milk begins to turn sour,
that is, when the sourness can just be recognized by the taste,
it has a rather disagreeable flavor. After more acid develops
the undesirable flavor largely disappears, and the milk assumes
a clean, desirable acid taste. The reasons for this have been
stated by Storch, the well-known authority on starters. He
claims that this disagreeable flavor is due to the action of unde-
sirable organisms, during the first souring stage. As the souring
progresses these germs are subdued and gradually crowded out
by the desirable acid-producing types. |

In the preparation of a starter the probabilities are that
some of these undesirable types of germs are present. At least
it is safer to go on the assumption that they are present. This
makes the underripening of starters just as important to guard
against as overripening.

Amount of Starter to Use.—The amount of starter will vary
under different conditions. It may vary from none at all to
as much as 50 per cent of the cream to be ripened. The quality
of cream is one of the factors that need to be considered. Raw
cream and old cream both require a large starter, especially if
the cream is thick enough to permit of being reduced in thick-

238 CREAM-RIPENING AND STARTERS

ness. Good pasteurized cream does not need a larger starter
than about 10 per cent of the cream to be ripened.

The amount of starter to use also depends somewhat upon
the general creamery conditions. In some creameries all the
cream is received in a very sour and poor condition, and facilities
for getting milk for preparation of starters are often very poor.
Under such conditions it is questionable whether it would be
profitable to use starters at all. The amount of starter to use
chiefly depends upon the degree of rapidity of ripening desired,
and upon the temperature of the cream. [If it is desirable to
ripen quickly, a comparatively large amount of starter (15 per
cent to 25 per cent) should be added, and the ripening tempera-
ture should be comparatively high (about 70° to 74° F.) If slow
ripening is desired, less starter may be used. Enough, however,
should be used to control the fermentation in the cream (about
ro per cent to 15 per cent), and the ripening temperature may be
lower, between 60° and 70° F. More
starter should be used in the winter.

Use of Starter-cans.—In the past,
ordinary tin shot-gun cans have been
used in most cases for the prepara-
tion of starters, and have given good
results. Some makers still use such
cans.

The earliest starter-cans were
made of light material and did not
last long. These defects, however,
have largely been done away with,
and the use of starter-cans certainly
is an improvement over the old

al ie * method of preparing the starters in
Fic. 81.—Improved Victor Starter several smaller cans.
a (Creamery Package Mig. These starter-cans are jacketed,

2 so that the temperature can be con-
trolled by using hot or cold water, or ice, as demanded, in
the jacket. All of the starter-cans have an agitator, which is
operated with a belt.

CHAPTER XVII
CHURNING AND WASHING BUTTER

Definition.—By churning we understand the agitation of
cream to such an extent as to bring the fat-globules together
into masses of butter of such size as to enable the maker to sep-
arate them from the buttermilk.

The agitation may be brought about in several different ways,

GE
AZZ
og ae

ZLLA

w—<—$x_
ain
wOw———_

> -—=

Fic. 82.—Ancient method of churning Fic. 83.—The Dash churn.
in skin bags.

and by different shaped devices; which are called churns. The
methods of churning, like the process of separation, began with
primitive methods. The ancients churned their milk, without
separation, in bags made from the skins of animals. The next
step in advance was to place milk or cream in bottles or jars, and
then to shake them. This latter method of churning cream in
bottles is yet in use in many of the smaller households of Europe,
where the amount of cream is limited to a small quantity donated
239

240 CHURNING AND WASHING BUTTER

by cow-owners. ‘The next step toward churning on a large
scale was to get a large wooden box or barrel run by power or by
hand. The churns which are in use at the present time in
American butter-factories are termed ‘‘ combined churns.”
They are so arranged as to admit of churning, washing, salting,
and working without removing the butter from the churn. This
style of churn is now being introduced into Europe. Owing
to their superior worth they will soon be in general use there as
well as here. They keep flies away from the butter during fly
time; the temperature of the butter can be controlled in the
churn, and the handling of the butter during salting and working
is obviated.

CONDITIONS AFFECTING THE CHURNABILITY OF CREAM

Temperature.— The temperature of cream is one of the most
influential factors in determining its churnability. The higher

Fic. 84. —Dual Churn (Creamery Package Mfg. Co.)

the temperature of the cream, the sooner the churning process
will be completed. Too high a churning temperature, however,
is not desirable. It causes the butter to come in soft lumps
instead of in a flaky granular form. ‘This is deleterious to the
quality of the butter. It causes, first, a greasy texture of the
butter, and, second, the incorporation in the butter of too much
buttermilk. This buttermilk contains sugar, curd, and water,

CONDITIONS AFFECTING THE CHURNABILITY OF CREAM 241

which, when present together in butter, are likely to sour and in
other ways injure the butter. Curd and sugar should be
excluded from butter as much as possible, in order to eliminate
food for bacteria which may be present.
An excess of curd is also favorable to
the formation of mottles.1

Too low a temperature is also un-
desirable, although it is better to have
the temperature a little low rather than
too high. When the churning tempera-
ture is too low, difficult churning is
likely to occur. Cream at a low tem- ,.. gre cue nal io
perature becomes more viscous. On Daal
agitation in the churn such cream, if it is
very thick, will adhere to the sides of the churn and rotate with it
without agitating; consequently no churning will take place.
- Too low a temperature brings the butter in such a firm condi-
tion that it takes up sait with difficulty, and when this hard

Fic, 86.—Perfection Dreadnaught Churn (J. A. Cherry Co.)

butter is being worked, a large portion of the water in the
butter is expressed, and the overrun will be lessened to a great
extent without increasing the commercial value of the butter.
The degree of hardness of the fat in the cream is the govern-
ing factor in deciding the churning temperature. The churning

1 Bul. No. 263, Geneva, N. Y.

242 CHURNING AND WASHING BUTTER

temperature will vary a great deal in different localities. The
hardness of the fat depends upon (1) the season of the year;
(2) the individuality of cow; (3) the stage of lactation; and (4)
the kind of food fed to the cows. All these factors influence the
melting-point of butter-fat. The
higher the melting-point of the
butter-fat is, the higher the churn-
ing temperature, and the lower the
melting-point of the fat, the lower
the churning temperature.

t. During the spring the cows
yield milk containing a larger pro-
portion of soft fats; consequently
the churning temperature is always
lower in the spring than in the fall
or winter. During winter, when
the cows are fed on dry food chiefly,
the harder fats increase in quantity, and consequently a higher
churning temperature is necessary during that time.

Fic. 87—Sectional view of Perfec-
tion working butter.

Fic, 88.— Disbrow churn (Davis-Watkins Dairymen’s Mig. Co.)

2. Some animals produce milk containing a larger propor-
tion of softer fats than do other animals. It is said that the
difference in this respect is more marked in certain breeds. It
is maintained that the cows of the Jersey breed produce milk

CONDITIONS AFFECTING THE CHURNABILITY OF CREAM 243

containing a larger proportion of the softer fats than do those of
any of the other breeds.

3. The period of lactation also affects the melting-point of
butter-fat. When a cow is fresh she yields a larger proportion
of the soft fats than she does
later on in the lactation period.
Just how much this change in
the hardness of the fat is due
to advance in the lactation
period and how much to
change from succulent to dry
feeds is not definitely known,
since the two parallel each
other so closely, it being the
common practice in this coun-
try to have the cows freshen
in the spring. According to
investigations conducted at the Purdue Station,! the melting
point of the fat lowers as a cow advances in her lactation period,
provided she is fed the same feeds throughout the year. If
these findings be correct, they mean that the influence of the
feed is much greater than that of the stage of lactation, since the
broad truth still remains, that under our conditions the propor-
tion of hard fats increases as the lactation period advances.
Witn this increase in the proportion of the hard fats in the
advancement of the lactation period, the fat-globules become
smaller. This, together with the increased hardness of the fat,
causes difficult churning at times.. It readily can be seen that
the larger the fat-globules are the greater are the chances for
these globules to strike each other during agitation in the churn-
ing process.

4. The nature of the food fed affects the melting-point of
butter to a considerable extent. Cotton-seed and its by-products
have been demonstrated thoroughly by several investigators to
cause butter to become hard. When a large amount of cotton-
seed is fed, the butter assumes a crumbly, tallowy, hard condi-

Fic. 89.—Sectional view of Disbrow.

1 Purdue Bulletin 159.

244 CHURNING AND WASHING BUTTER

tion; while linseed meal, and practically all succulent foods, tend
to decrease the melting-point of butter-fat.
According to the above it can be concluded that the churning

Fic. 90..—Master dual churn (Creamery Package Mfg. Co.)

temperature may vary between wide limits, but the average
desirable churning temperature under normal conditions is
between 50° and 60° F. It may, and does, go outside these
limits at times; for in-
stance, Many cream-
eries find it necessary
to churn at a tempera-
ture under 50° F. in
the early part of the
summer season, when
the grass Is very young
and succulent and the
proportion of soft fats
is very high. Any con-
ditions which tend to
harden the butter-fat
will require a comparatively high churning temperature; and
any conditions tending to soften the butter-fat will require a

Fic. 91—Simplex churn (D. H. Burrell & Co.)

CONDITIONS AFFECTING THE CHURNABILITY OF CREAM 245

lowering of the churning temperature. The lower the tempera-
ture at which the churning can be successfully accomplished, the ©
more complete will be the churning; that is, the less fat will
remain in the buttermilk.

Influence of Length of Time Held at Churning Temperature.—
The length of time that cream is held at the churning tempera-
ture is a factor that must be considered. If it be found necessary
to churn cream soon after cooling it, it should be cooled to a
lower temperature than would otherwise be necessary. Cream
should be held at least two hours at churning temperature before »
it is churned—hbetter a longer time. It takes this length of time
at least for the fat, which is a poor conductor of heat and firms
_ slowly, to reach the temperature of the serum of the cream and
become firm.

In the same creamery, with cream of the same richness, we
have observed that cream churned immediately after cooling
_ would churn as readily at 51° to 52° F. as cream held at 56° F.
overnight and churned without change of temperature. The
per cent of fat was much lower in the buttermilk from the cream
held overnight than it was in that from cream churned soon after
being cooled.

Richness of Cream.—The amount of fat in the cream affects
the churnability of it considerably. The richer the cream the
sooner will the churning be completed, that is, providing the
cream is not rich enough to be so thick as to cause it to adhere
to the inside of the churn and thus escape being agitated. If
rich cream is churned at a high temperature the butter will come
in a remarkably short time, providing all other conditions are
cavorable. Thin cream churns much more slowly, and can be
churned at a higher temperature than thick cream, without
injuring the quality of the butter. When rich cream is churned
at a high temperature, and the butter comes in a short time
(about ten minutes), the butter will usually be greasy in body,
and will contain a great deal of buttermilk, which will be more
or less difficult to remove on washing. When thick cream is
being churned, the butter does not break in the form of small
round granules, as it does when thin cream is churned.

246 CHURNING AND WASHING BUTTER

When thick cream is churned at as high a temperature as is
consistent with getting a good texture, the best results are
obtained. In the first place, rich cream produces less butter-

Fic. 92.—Victor heavy duty churn (Creamery Package Mfg, Co.)

milk, consequently less fat will be lost in the buttermilk. This
would tend to increase the overrun. Secondly, the breaking
of the butter at the end of the churning will be such as to cause

Fic. 93.—Sectional view of
four roll Victor working
butter,

the granules to appear large and flaky,
rather than small and round. The
more flaky granules of butter will
retain more moisture than the smaller,
harder granules under the same treat-
ment. Experiments show that when
different thicknesses of cream (thin
cream containing on an average 22 per
cent of fat, and thick cream 36 per
cent of fat) are churned, there is a dif-
ference of about 3 per cent in the mois-
ture-content of the butter. The aver-

age churning temperatures of cream and wash-water in these
experiments were 56° and 53° F. respectively.
When thick cream is churned, and the temperature is mod-

CONDITIONS AFFECTING THE CHURNABILITY OF CREAM 247

erately high, it is almost impossible to churn the butter into
granules. ‘This condition causes butter from thick cream to
contain more moisture than butter from thin cream.

Amount of Cream in Churn.—When the churn is about one-
third full, the greatest degree of agitation is obtained, and con-
sequently a quicker churning. If a small amount of cream is
being churned, it is often difficult to gather the butter properly.

) joest= io | joss 9 io |

©

vo o10 ic= 5 Sof (

Fic. 94.—Danish churns and frame for holding them.

If the cream is thin, the granules are thrown about in such a
way that they are gathered with difficulty. If the cream is
thick, the small amount of cream will adhere to the inside of the
churn, and in that way delay the completion of the churning.

It is a common opinion that less overrun is obtained from
a small churning than from a large churning. It is safe to say
that if it were possible to maintain all conditions alike, especially
as to temperature and degree of churning, there would be very

248 CHURNING AND WASHING BUTTER

little difference in the moisture-content of the butter made from
churnings of different sizes. When there is only a small amount
in the churn, the atmospheric temperature is likely to raise or
lower the temperature of the cream. If the atmosphere is
warm, then the butter from the small churning is more likely
to be soft. A small amount of cream in the churn is also more
likely to be overchurned than a larger amount of cream. ‘These
two factors would tend to increase the amount of water in the
butter. In mixing the salt with a comparatively large amount
of butter, less working is necessary. Much of the butter is
mixed in the churn without going through the workers, and con-
sequently less moisture will be expressed from the butter. With
the same number of revolutions of the churn the butter from
the small churning is worked correspondingly more than the
butter from a larger churning. Medium firm butter, to a certain
limit, loses about .2 per cent of moisture for every revolution that
it is overworked in the absence of water.

Degree of Ripeness.—The riper the cream is, all other con-
ditions being the same, the easier it will churn. Sweet cream
is viscous, and consequently the fat-globules will not unite as
readily. The acid developed in the cream seems to cut or reduce
the viscosity of the cream, although it causes it to become thicker
in its consistency. Cream in an advanced stage of ripening is
brittle, so to speak; that is, if a sample of the properly soured
cream is poured from a dipper it will not string but break off in
lumps.

If very thin cream is overripened, the curd is coagulated.
When this thickly coagulated cream is churned, the solid curd
breaks up into small curdy lumps. These small lumps of curd
are likely to incorporate themselves in the body of the butter
and injure its quality, and also its keeping quality. If thin
cream has been overripened, it should be strained well, and
care should be taken not to churn it to such a degree as to
unite the granules into lumps before the churn is stopped. If
the churn is stopped while the butter is in a granular form, the
most of these curdy specks can be separated from the butter
by copious washing. Some specks are likely to remain in the

CONDITIONS AFFECTING THE CHURNABILITY OF CREAM 249

butter when the cream is in such a condition, but by following
the plan outlined enough of the specks can be removed from the
butter so that its commercial quality will not be injured. The
degree of ripeness of cream does not have any effect upon the
composition of the butter, except in increasing the curd content as
mentioned.

Nature of Agitation.—The nature and degree of agitation of
cream affect the churnability considerably. Many different
kinds of churns are on the market at the present time. The
rotary drum-churns, now used almost universally in this country,
are claimed to give the greatest degree of agitation; that is,
providing the churn revolves at a proper rate of speed. If
the speed is so great as to cause the cream to be influenced by
the centrifugal force generated, rotating it with the churn, then
no agitation will take place. Consequently the churning
“process will be delayed, if not entirely prevented. If the
speed of the churn is too slow, the degree of agitation of the
cream will not be at its maximum, as the cream will tend to
remain at the lowest portion of the churn without being agitated.

In the old-fashioned dash-churn the cream was not exposed
to much agitation. In Europe the upright barrel-churn with
rotary stirrers inside is mostly used. It is slower than American
churns, but gives good satisfaction.

Extensive investigational work conducted by the American
Association of Creamery Butter Manufacturers, under the
direction of one of the authors, has shown that there are
several factors which have a direct bearing upon the exhaustive-
ness of the churning of cream. With very sour cream that
has been pasteurized, the loss of fat in buttermilk is much
larger than is generally recognized by buttermakers. The
average loss of fat in buttermilk, according to hundreds of
analyses made by the American Association of Creamery
Butter Manufacturers, is more than five-tenths of one per cent.

The loss of fat in buttermilk varies somewhat with the
seasons of the year. During the hot weather in the summer
months, especially in the flush, the loss of fat in buttermilk
is greater than in the fall and winter months. One creamery

250 CHURNING AND WASHING BUTTER

that makes a practice of testing its buttermilk daily reported
to us that for the months of June and July their average loss was
.85 per cent, some samples running as high as 1.25 per cent.
Their tests were made by the Mojonnier method. So there
is no question concerning the accuracy of the results obtained.

The high per cent of fat found in buttermilk during the
period when cream is very sour is no doubt caused by the
high acid coagulating a portion of the casein into small hard
lumps, which are not entirely broken up by the process of
neutralization or churning.

Another thing that will affect the loss at this period is,
the amount of cream received is very large; buttermakers are
crowded with work, churns are filled too full, and cream is not
held for a long enough period at churning temperature to
thoroughly chill the fat. The result is that the large globules
unite quickly in the process of churning, due to the soft condi-
tion of the fat, and the smaller fat globules are carried off in
the meshes of the casein into the buttermilk. It may be
possible that the high acid in the cream partly removes the
film from the larger fat globules, and in the process of churning
they break up into smaller particles of fat. We have no
positive knowledge that this is the case.

In the investigation pursued by the American Association
of Creamery Butter Manufacturers it was found that where
the churn is filled about one-third full and the cream is held
for several hours, or overnight, at churning temperature a
more exhaustive churning is obtained than where cream is placed
in the churn immediately after being cooled. Where the lack
of churn or vat space compels quick churning of the cream,
it is better to cool the cream down four or five degrees below
the normal churning temperature. The temperature that
cream can be churned at will depend upon the per cent of fat
in the cream. Cream that contains from thirty to thirty-five
per cent fat can be churned at a very low temperature, especially
cream that contains a high per cent of acid.

The speed of the churn has also a direct bearing on the
temperature at which cream can be churned, and also a bearing

CONDITIONS AFFECTING THE CHURNABILITY OF CREAM 251

on the loss of fat in the buttermilk. The speed of the churn
will depend, to some extent, upon the diameter of the churn
and the kind of churn used. We find the following speeds give
very satisfactory results:

Simplex churn, 24 revolutions per minute.

Disbrow, Victor, Dual and Perfection churns, from 32 to
35 revolutions per minute.

Where a churn is run at a low speed, the temperature of
the cream will have to be higher to cause the fat globules to
unite, due to the lack of sufficient agitation.

From microscopical examination made of buttermilk, where
the loss was high, it was found that the fat seemed to be lodged
in the meshes of the casein. When placing buttermilk in bottles
in the laboratory and permitting it to stand overnight, and
taking samples from the upper or watery portion, the test of
fat in this liquid portion was very low, while in the lower por-
tion, which contained the casein, the per cent of fat was
exceedingly high.

The following tests of the upper and lower portions of twelve
samples of buttermilk from different churnings were made after
allowing the samples to stand in half pint bottles overnight.
About half the liquid, or the upper portion of the buttermilk,
was decanted from the bottle in each instance, and a comparison
of its test was made with that of the lower portion.

Number Test of upper Test of
of sample | liquid portion lower portion

I .48 I.07

2 20 50

3 20 50

4 18 .56

5 38 .60

6 02 r.06

7 30 -39

8 I4 .38

9 18 .44

10 14 a5

IT .18 3 Wak

I2 II 58

252 : CHURNING AND WASHING BUTTER

Cream that is separated from sweet milk at the creamery
can be ripened or soured to a fairly high degree of acidity
without having the lumpy condition referred to, above, and
a very exhaustive churning can be had from the same,
whether pasteurized or unpasteurized. Where various lots
of sour cream are received at the creamery, the average per
cent of acidity of the entire lot when mixed together may
not be very high, but some portions of this cream possibly have
contained an acidity of well over 1 per cent; hence, the
loss of fat in such cream would be greater than if the cream
had been separated from sweet milk and where the souring
was under the control of the maker. To get an exhaustive
churning with sour cream, the same should have the acidity
reduced to a low degree. Partial neutralization has the
effect of putting the casein in a more flocculent condition;
hence, the loss is not as great.

Neutralization should always be done before pasteuriza-
tion, as otherwise the heat of pasteurization will precipi-
tate some of the casein into hard lumps, which will not
be broken by the agitation of the churn in the process of
churning.

As far as the working of butter goes, any of the modern
churns will do efficient work, especially when the maker has
got himself accustomed to the churn he is operating.

Size of Fat-globules.—Cream containing large fat-globules
churns more quickly than cream containing small globules and a
more exhaustive churning can also be obtained from it. It is,
however, impossible to obtain cream which does not contain any
of the small globules. The minute globules are always difficult
to remove from the serum, whether it be in the churning or in
the separation. In the churning there is a certain force which
always tends to hold the globules in place. This force acts in a
correspondingly greater degree upon the small globules. They
are held in position and move only when the cream is exposed to
agitation. Cream containing larger globules allows them to
escape from their position with greater ease than does cream
containing the minute globules. The globules which are not

COLOR 253

removed from the buttermilk during the churning process are
largely of the small type.

Straining of Cream.—Before the cream is transferred from
the ripening-vat to the churn it should be strained through a
fine perforated tin strainer. This can be conveniently done
during the changing of the cream from the ripening-vat to the
churn. Special strainers are now manufactured which can
be hooked onto the churn, and the cream can run directly from
the ripening-vat through the strainer into the churn. This
straining of the cream separates all the lumps which cre likely
to appear. It also separates any other coarse impurities which
may be present. If these impurities were not separated they
would probably be embodied in the butter and cause an unsightly

Fic. 95.—Cream and milk strainer.

appearance. They would also be likely to injure the keeping
quality of the butter, but this would depend, of course, upon
the character of the impurities.

Color.—In order to maintain a uniform color in the butter
during the different seasons, it is essential that some artificial
color be added at certain times. During the latter part of
May and the early part of June the butter has a rich yellow
color, which is accepted as the standard color of butter. This
is often referred to as the “ June color.”

There are several different butter-colors on the market, for
which special merits areclaimed. All the colors, so far as known,
are efficient in imparting color to the butter without materially
coloring the buttermilk. A good butter-color should be a sub-
stance which does not impart a bad smell or taste to the butter.
It should possess strong coloring properties, so that very little

254 CHURNING AND WASHING BUTTER

of it would have to be added in order to impart the desirable
color. It should not be injurious to health. Some colors are
prepared from the fruit of the annato tree, which grows in the
East Indies and South America. The coloring matter on the
inner part of the covering of this fruit is dissolved in a suitable
oil, such as sesame or hemp.

Before any of the proper commercial butter-colors were put
upon the market, extracts of carrots, marigold, saffron, and
annato were used. The yolk of eggs has also been used to
some extent. It is said that carrot-juice is the most healthful
butter-color.

The amount of color to add depends upon the market require-
ments, and upon the season of the year. As was mentioned
before, in June little or no color should be added. As the summer
season advances the amount of color added can be gradually
increased. During winter, while the cows are on dry feed,
the maximum amount of color is generally used. Color require-
ments of the butter vary considerably at the same season of the
year. American markets demand a higher color than European
markets. The northern markets desire a light straw color,
while the southern markets want a deeper color, almost an
orange color. The Jewish trade requires uncolored butter.
In some of the European countries no color is used. The
English market, which is the greatest butter market in the world,
demands butter that has a very light straw color. The main
object in coloring butter is to maintain a uniform color during
the different seasons of the year. The amount of color to add
during the different seasons will usually vary between none and a
trifle over 2 ounces for every 100 pounds of fat.

The color should be added to the cream before the churn
has been started. If this has not been done, the butter can be
colored by mixing the color with the salt. The salt should
then be well distributed and worked into the butter until the
body of the butter assumes a uniform color. The chief objec-
tion to this method is, that it is difficult to work in the color
thoroughly without injuring the butter.

The sole object in adding color is to give the butter a more

WHEN TO STOP THE CHURNING 255

attractive appearance. It neither adds to nor takes from the
flavor or food value of butter. Hence the shade of color should
be such as will make the butter most attractive in appearance.
This varies somewhat with the market to which the butter is
going.

When to Stop the Churning.—Different makers have various
ways of ascertaining when the churning process has been com-
pleted. Some determine the proper churning stage by the size
‘of granules, others by the height at which the butter floats in
the buttermilk. Others again depend upon the appearance of
the buttermilk. It is well to let all of these factors influence
the operator in deciding when the churn should be stopped, as no
one of them may be a sufficient indication.

The size of the granules is the most common factor that
determines the time when the churn should be stopped. It
has been a general rule in the past to stop the churning when
the granules are a little larger than wheat-kernels. As a rule
it is safer to carry the churning on a little further until the
granules increase to the size of corn-kernels, irregular and flaky
in shape. At this stage the buttermilk will usually appear
bluish in color, and the butter is raised above the buttermilk
a considerable distance. When the butter is churned to too
small granules, many of them will go through the strainer into
the buttermilk, and cause a considerable loss. When butter
in such shape is washed in medium-cold wash-water, the granules
continue to remain in a separate state. When salt is added,
the moisture is extracted from them, and the water is likely to be
caught in holes and crevices during the working and cause leaky
butter. If the churning is carried on a little further, the granules
will not escape into the buttermilk, the churning will be more
complete, and the moisture will be incorporated in a better con-
dition.

Overchurning should be avoided as much as underchurning.
If butter is overchurned in the buttermilk, it will retain a large
amount of the buttermilk, which will be very difficult to remove
by washing. Overchurning butter, especially at a medium-
high temperature, is very effective in increasing the moisture-

256 CHURNING AND WASHING BUTTER

content of butter, and should be guarded against for that reason.
Butter containing more than 16 per cent water is not permissible
on the American market.

When cream is in a poor condition it should not be over-
churned, as the incorporation of buttermilk produces a very
rank and unclean flavor in the butter. Cream in such condi-
tion also contains many undesirable germs, which, when incor-

1 2 3 Bae 5

Fic. 96.—Butter from 1 pound of fat in cylinders, showing the effect of differ-
ent percentages of water upon quantity. The water-content of these samples
ranges between 8 per cent and ig per cent,

porated into the butter, will cause it to deteriorate to a great
extent. When the cream is in poor condition, the churn should
be stopped as early as is consistent with the completeness of
churning. The buttermilk should be removed and the butter
washed thoroughly in clean, pure wash-water. If the wash-
water is added while the butter is in this granular condition, the
buttermilk can be very effectively removed. If one washing is
not sufficient, wash three or four times. In such a case the tem-

CONDITION OF WATER IN BUTTER 257

Fic. 97.—Butter sample, Fic. 98.—Butter sample,
15.61 per cent water. 15.31 per cent water.

Fic. 99.—Butter sample, 13.37 per cent water; leaky, 2 per cent brine.

Microscopical views showing condition of water in butter. Fig. 97 shows that
the water has been incorporated in the form of very minute particles. Storch
found from nine million to sixteen million water particles per cubic millimeter.
Such butter appears dry and a little dull. Fig. 98 shows the water incor-
porated in medium-small particles. There were on an average three and three-
fifths millions of water particles per cubic millimeter in such butter. F ig. 99
shows condition of water in leaky butter. Storch found about two and one-

half million water particles per cubic millimeter in butter having such a body.
(Views by Storch.)

258 CHURNING AND WASHING BUTTER

perature should be low. If the temperature of the wash-water
is high, and the butter is washed excessively, it will contain too
much moisture when it is finished, and is likely to be salvy.
If washed with water at a low temperature the butter will not
incorporate so much water. What it does incorporate in excess,
will, as a rule, be expressed during the working of the butter—a
result due to its firmness.

If the attempt is made to incorporate water by working the
butter in water after the salt has been added, while the butter is
in a hard, granular condition, it will usually appear leaky.

If cream is in a good condition, overchurning to a small extent
does not produce any bad results. The germs which are present
in pure and well-ripened cream are not deleterious to the keeping
quality of the butter. The amount of butter-milk incorporated
in the butter is not sufficient to cause any bad effects upon its
quality. If the cream is in proper condition it is diffcult to
incorporate any more than 3 per cent of curd into the butter.
While overchurning is not to be recommended, if it is at any time
desirable, it should be done in the washwater rather than in the
buttermilk.

Churning Mixed, Sweet, and Sour Cream.—When two lots of
cream are to be churned, one sweet and the other sour, they
should be churned separately. If the two lots of cream are
mixed together, the sour cream churns more quickly than the
sweet cream. As a consequence the churn is likely to be
stopped before the fat from the sweet cream has been completely
separated from the serum.

At some of the creameries conditions are such that the oper-
ator may be tempted to mix the two lots of cream. Where
sweet cream arrives at the creamery just previous to churning
time, it is advisable not to mix the sweet cream with the sour.
It is, as a rule, better to carry the sweet cream over to the next
churning, or, if necessary, churn it separately.

Difficult Churning.—Difficult churnings in creameries are
not very common. In farm butter-making they are more fre-
quent, especially in the fall. At this time the cows are usually
well advanced in the period of lactation, and early in the winter

DIFFICULT CHURNING 259

they are often fed on food which causes hard butter fat, as
described under “ Effect of Food upon Fat.” In the fall or
early winter, a large portion of the milk is usually obtained
from strippers, or cows almost dried up. Such milk contains a
large portion of the small fat-globules. Difficult churning
resulting from such conditions can usually be remedied by ripen-
ing to a higher degree of acidity and churning the cream at a
higher temperature.

Complaints are occasionally heard of difficult churning which
cannot be remedied by such treatment. Sometimes cream froths,
and will not agitate in the churn. Such a frothy condition has
in some cases been found to occur even though the cream may
seem to be in an ideal condition for churning. It is believed
by some, notably Hertz, that such a condition in the cream is
brought about by a disease of the cow. Weigman has studied
and isolated a ferment which caused a soapy condition of milk
and cream. It is possible that such exceedingly difficult cases
in churning may be due to a disease of the cow, and it may also
be due to certain ferments that produce a soapy condition of the
cream.

If thick cream at a very low temperature is put into the
churn, it sometimes causes difficult churning. When such
cream is first agitated in the churn it incorporates considerable
air. This air, together with the various gases developed at a
low temperature, does not readily escape. The viscosity of it is
so great that it will not release the air present. As a conse-
quence it assumes a stiff consistency, much the same as the beaten
white of an egg. If cream froths in the churn as mentioned,
a little warm water thrown on the outside of the churn will
often start the agitation of the cream within. If a combined
churn is used the rollers may be put in gear, and the churn
revolved in slow gear. This will often start the cream to agitate.
Tf these two remedies are not sufficient, a little water, lukewarm if
necessary, may be added directly to the cream. By letting
the churn stand a short time, the cream will usually condense
into a liquid form again, and many times the churning process
can then be completed. This latter method, however, usually

260 CHURNING AND WASHING BUTTER

requires more time than can be profitably spared. If the churn-
ing difficulty is of a serious nature the remedies are:

(1) If produced by a certain cow, or herd, find out whether
it is produced by a fermentative process, or by other abnormal
conditions of the cow.

(2) Change the food of the cow. A succulent food will
usually cause the cow to secrete more milk, and of a different
nature.

(3) If produced by a ferment, endeavor to control the fer-
mentation as previously described.

(4) Ripen the cream to a higher degree of acidity.

(5) Skim thicker cream and churn at a higher temperature.

The last three methods will cure most cases of difficult
churnings.

Keeping Churn Sweet.—It has been mentioned before that
butter absorbs foreign odors very readily. If the churn is not
kept in a pure, sweet condition, the butter will be exposed to the
undesirable odors and its commercial quality will be impaired.
The best butter cannot be produced in a foul-smelling churn.
As churns often are not used every day, they very readily assume
this impure condition, and it is essential that special care be
taken in keeping them clean.

The best method of keeping churns in good condition is to
rinse the churn in two waters at the end of each churning.
The first rinsing should be made with lukewarm water, the
second with scalding hot water. Some prefer to turn the
churn over with mouth down. Others prefer to allow the cover-
hole to turn up. When the churn is turned with the cover-
_ hole down, the remaining steam on the inside of the churn will
not escape. It will condense inside of the churn, and cause the
churn to remain in a damp condition overnight or even longer.
If the churn is turned with the cover-hole up the dust and other
impurities, if present, are likely to settle into the churn. A good
way is to turn the churn over so that the cover-hole points to
one side. The churn should be thoroughly drained first, other-
wise some water will remain in the bottom. When the churn
is left with the cover-hole at one side, the steam can escape,

KEEPING CHURN SWEET 261

and the heat absorbed from the wash-water will dry the churn
thoroughly. Many makers rinse the churn only once and use
scalding hot water. This method is likely to scald the remaining
curd on to the wood; secondly, one rinsing is net enough to
insure a clean churn. ‘The first rinsing with lukewarm water
removes the major portion of the buttermilk and brine, and to a
certain extent warms the wood of the churn, so that when the
second rinsing with scalding hot water is completed, the churn
has been thoroughly scalded. In addition, the churn is clean,
and no food is left on which germs can thrive. The churn is
also left warm, and in that condition will dry quickly.

Some makers prefer to keep the churn in a good condition by
sprinkling salt on the inside after washing. ‘This is not to be
recommended, as all churns contain more or less iron-ware on
the inside. Salt, while a fair germicide, causes the formation
of rust on all iron with which it comes in contact. After a time
this rust will scale off to a certain extent and become incorporated
with the butter.

If the churn is treated daily in the manner described above
and then at the end of the week treated with slaked lime,
it can be kept in a good sweet condition. The lime should
be freshly slaked and in a liquid condition when put in the churn.
A pailful or two of this fluid will be sufficient for each churn.
By rotating the churn a few times the lime will be spread all
over the inside of it. Let the churn remain in this con-
dition until ready for use again. When ready for use, put in
lsome warm water, and the lime will readily come off. But if
it has been allowed to remain in the churn too long, it will form a
lime carbonate, and will be more difficult to remove.

Lime is one of the best disinfectants and deodorizers that can
be used in a creamery. Some of the best butter-makers use it
every day on all the wooden utensils, such as butter-workers,
churns, etc. Lime can be used more advantageously in Amer-
ican creameries than it is to-day. Many creameries would be in
a much sweeter and purer condition if they were given a good
coat of whitewash on the inside once a month. Refrigerators,
wooden utensils, and rooms of any kind can be kept in a good,

262 CHURNING AND WASHING BUTTER

sweet and pure condition by whitewashing or sprinkling a little
lime on them.

In the preparation of a new churn for use it is a good plan
to treat it with milk of lime in the manner already described.
It will fill the pores of the wood and harden it, and remove all
danger of imparting a woody flavor to the butter of the first
churnings made in the churn.

To Prevent Butter from “‘ Sticking ” to the Churn.—At times
churns get into a condition in which butter sticks or adheres to
them more or less. Sometimes it requires treatment with a weak
acid solution to overcome this difficulty, and sometimes treatment
with an alkali solution is needed. If treatment with acid is
what is needed, a weak solution of either sulphuric or muriatic
acid may be used—say a pint to too gallons of water. The
acid must be added carefully to the water in the churn and
none of it must be poured directly upon the wood. ‘The churn
is revolved with this solution in it, for about five minutes at a
time, at intervals extending over a period of several hours.
It is then rinsed with warm water and then with water containing
a little of some good washing powder, such as Wyandotte.
If treatment with an alkali solution is needed, which is the case
if fat has soaked into the wood, a suitable washing powder may be
used to remove the difficulty. The following is an extract from
a letter received from one of our leading creameries which had
written for and received suggestions from one of the authors for
overcoming this difficulty: ‘‘ We received your letter in regard to
the trouble we had with the butter sticking to our churn. We
are pleased to advise that we have apparently eliminated all
of this condition. When we received your letter suggesting
remedies which might stop this condition, we at first used the
muriatic acid but without any results whatever. Then our
butter-maker took about three pails of Wyandotte, put in a small
amount of water and heated with steam until he made a sort of a
paste out of it. He then put it in the churn and gave it several
revolutions and let it stand overnight, then washed it out
thoroughly with hot water. The first time it seemed to help
it very considerably, so we gave it another dose a day or two

WASHING OF BUTTER 263

later and it has relieved the whole condition. He is of the
opinion that if this is used when the butter shows any ten-
dency to stick to the churn, it will keep the churn in good con-
dition right along.”

WASHING OF BUTTER

Purpose of Washing. The chief object of washing butter
is to remove as much buttermilk as possible. The more impure
the cream is, the greater is the importance of getting the butter
thoroughly washed. In the winter, when it is cold, and the
cream is in good condition, some makers do not wash the butter
at all. But this is not a safe method. The removal of the
buttermilk constituents should be as complete as conditions will
permit.

Temperature of Wash-water.—The temperature of wash-
water should be as nearly like that of the cream when churned
as is consistent with the other conditions. It is quite a regular
practice in many creameries, particularly in summer, to temper
the wash-water to about 2° below the churning temperature of
the cream. Extreme and rapid changes in temperature should
always be avoided. Occasionally it is necessary to use water
that is colder than the cream; at other times it is necessary to
use wash-water at a higher temperature than that of the cream.
If the butter churns soft, do not use ice-cold wash-water to chill
the butter, as it has a tendency to give butter a tallowy appear-
ance. Neither should hard butter be quickly softened by using
wash-water at a very high temperature, as it is likely to cause the
butter to assume a greasy and slushy texture. If it is necessary
to change the degree of hardness of the buiter, change it grad-
ually by using water at a moderate temperature and allowing the
butter to be in contact with it a longer time without agitating
it much.

The regulation of the condition or degree of firmness of butter,
for the proper working of it, should never have to be accom-
plished to any great extent by means of the wash-water. This
is not the real purpose of washing butter. If the churning tem-

264 CHURNING AND WASHING BUTTER

perature of the cream be right, the butter will be in proper con-
dition for washing and working. If the churning temperature
be not right it is difficult through any device that may be
adopted subsequently—such as tempering the wash-water—to
bring the butter into the best condition for salting and working.
Regulation by means of a change in temperature of the wash-
water will prove a partial, but not a complete remedy—par-
ticularly if the butter be very soft when it comes.

Unless the butter is of very poor quality, excessive washing
should be avoided. Cold water is said to absorb a considerable
portion of the flavoring substances. If the quality of the butter
is poor, many of the undesirable flavors and odors are removed
by excessive washing; while if the butter has a fine, rich flavor,
it should be retained, and not extracted by washing the butter
more than is needed. No definite temperature can be given, as
the temperature of wash-water must vary according to the hard-
ness of the butter when churned.

If the temperature of the wash-water is too high, and the
churning in the wash-water is continued a very long time, much
water will be incorporated in the butter. If the butter is quite
firm in the first place, and the temperature of the wash-water
is not above 60° F., there is not much danger of getting too
much water in the butter. Rapid changes in the degree of
hardness of the butter in the presence of water are conducive to a
high moisture-content. Very soft butter chilled in very cold
water, and hard butter softened in very warm wash-water are
two conditions which should be avoided.

As to the quantity of wash water that should be used: with
cream of average richness, it will be about the same as that of the
buttermilk; with very rich cream a little greater. In washing
the butter the churn is usually run from ro to 15 revolutions on
high speed. Some, instead of following this practice of churning
the butter in the wash water, run the churn about 2 to 5 revolu-
tions at slow speed with the worker in gear; modifications and
combinations of these two methods are made. For instance,
where butter is first washed or sprayed and a second wash-water
is used, some adopt the practice, during the second washing, of

WASHING OF BUTTER 265

revolving the churn a few times on high speed while others put
the rolls in motion using the slow gear.

Butter from cream of good quality, churned at the right
temperature, needs less washing than butter from cream of poor
quality or butter churned at too high a temperature. Two
washings should suffice when the cream is of good quality, and
with such cream some wash the butter only once if the wash-
water runs off clear. In order to possess good keeping qualities,
butter must have the buttermilk well washed out of it. Butter
from cream of poor flavor requires more washing than butter
from cream that is clean in flavor.

Kind of Wash-water to Use.—In the washing of butter, it is
very essential that water used should be the best obtainable.
The creamery water-supply is evidently much better now than
it was years ago. Pond-wells and shallow wells are gradually
passing out of existence, but there are yet many shallow wells
from which water is drawn for creamery purposes. Water from
wells may appear to be pure, and yet contain germs which are
deleterious to dairy products, and especially to the keeping qual-
ity of butter. That water of average purity contains such germs
has been demonstrated in this country, as well as in foreign
countries. Shallow well water contains on an average about
15,000 germs per cubic centimeter, but Miquel has found that a
rapid power of multiplication characterizes the bacteria in pure
spring-water, while in impure water the multiplication is slower.
Water containing only this number of germs is, as a rule consid-
ered very pure. Most creameries, however, pump their water
into a tank overhead in the creamery, where it is contaminated
with bacteria and impurities of different kinds.

Shallow wells are usually surrounded with conditions which
do not guarantee a creamery pure water during the different
seasons of the year. In the spring, when rains are frequent and
heavy, unwholesome surface-water is likely to seep in through
the sides. Such wells may also serve as traps for small animals.
The presence of an animal in the well is sure to cause undesirable
odors and a multitude of undesirable and putrefactive organisms.

Water from deeply drilled wells, even if it is pure in so far

266 CHURNING AND WASHING BUTTER

as its germ-content is concerned, is in many cases turbid and
sandy, and needs to go through a process of purification as much
as does the shallow well water.

METHODS OF PURIFYING WASH-WATER

There are two practical and effective methods of purifying
wash-water, viz., (z) Filtration, and (2) Pasteurization. Which
of these two methods is the most practicable and the most
effective in the creamery depends upon the conditions and upon
the quality of the water. In the case of water from deep wells,
which contains little or no organic matter, but at the same time
is infested with undesirable germs, pasteurization is perhaps
more expedient. Filtration, if the same degree of thoroughness
is to be reached as in pasteurization, is a comparatively slow
process. Pasteurization of wash-water is a trifle more expensive
than filtration. Wash-water can be pasteurized at the same
time that the churning is being done, thus economizing in time
and fuel. Pasteurization is quite effective in rendering the water
germ-free, but it is not so effective in removing any organic
matter or other tangible impurities which may be present. If
the creamery does not already have a pasteurizer, filtration can
be employed very profitably, and under average conditions it
will perhaps give the best results.

Filtration.—Filtration is inexpensive, and is a very efficient
- method of purifying wash-water. It seems strange that bac-
teria can be removed from water by passing through layers of
sand, gravel, coke, and charcoal, but such is the case. Filtra-
tion is applicable to all kinds of water; even if the water appears
pure, it is well to filter it. Fewer germs and fewer varieties
of micro-organisms are apparently found in deep well water
than is the case in water from surface-wells; hence the ferments
which are present will have a free field for developing in the
absence of competing forms. If a sample of water which is
rich in micro-organisms is violently shaken with a certain
amount of charcoal, coke, chalk or similar substances, and then
left for a time to settle, the pure layer of water at the top will be

METHODS OF PURIFYING WASH-WATER 267

almost entirely free from germs, and in some cases entirely
sterile. It used to be thought by older German investigators
that these different filtering substances had almost miraculous
power of removing organisms from water.

The factors which are to be considered in successful filtration
are:

(x) Storage capacity for unfiltered water.

(2) Construction of filter-beds.

(3) Rate of filtration.

(4) Renewal of filter-beds.

(1) Concerning the storage capacity, nearlv all creameries
have storage-tanks overhead in the creamery; so far as that is
concerned, however, filtration can be successfully carried on
continuously as well as intermittently.

(2) The construction of the filter-bed used in the experi-
ment carried on at the Iowa Experiment Station, Ames, Iowa,
is as shown in Fig. ror. The approximate proportionate depth
of each layer in the bed is as follows, beginning at the bottom:

_ Two inches small flint stones; 22 inches fine sand; 12 inches
fine coke; g inches charcoal; 2 inches fine stone or coarse gravel.
The layer of fine sand should not be less than 15 inches. It has
been asserted that a few pieces of old iron mixed in the filter-bed
are beneficial. Alum, lime, and copperas have been recom-
mended for clarifying and deodorizing very impure water. As
these substances are soluble they should not be used in filter-
beds, which are intended for the filtration of water for potable
purposes. The filtering-can was made from 22 galvanized iron.
The height of can is 48 inches; diameter, 18 inches. The bottom
of the can is slanting towards the faucet, or opening. Thus
no water is permitted to stand on the bottom and afford oppor-
_ tunities for germs to accumulate. On the inside are three plates.
One lies horizontally, near the bottom, and upon it the filtering-
material rests. Another lies on the top of the fine sand. Both
of these plates were perforated with many small holes. Near the
top is placed a concave plate with a hole near the center. This
plate directs all the water to the center of the filter-bed, and thus
the water gets the full benefit of the filtering process. The

268 CHURNING AND WASHING BUTTER

total cost of this filtering-can when complete was $11.11. Since
the time when this can was constructed prices have advanced
considerably. |

(3) The rate of filtration is necessarily governed by the depth
of the filter-bed, the character of the material used, and its

ZG
ZUSSUr
~' Seah

Fine sand

FIG. 100. Fic. rot.

Fic. 100.—Filter-can; 1, overflow; 2, inlet of tap-water; 3, outlet of filtered water.

Fic. tor.—Cross-section of filter-bed and can: 1, overflow; 2, inlet; 3, outlet of
filtered water; 4, perforated galvanized-iron plate; 5, perforated galvanized-
iron plate; 6, concave galvanized-iron plate with hole in center.

fineness. The water passes through the charcoal, coke, and
gravel quite rapidly, yet the substances are very strong barriers
to the passage of micro-organisms. The sand layer does not
admit of such rapid filtration. Fine sand, however, is one of the
best filtering substances that can be had. The rate of filtra-
tion can be regulated by increasing or decreasing the depth of the

METHODS OF PURIFYING WASH-WATER 269

fine-sand layer. In a general way, the slower the rate of fil-
tration is, the more thorough it is; and, vice versa, the more rapid
the rate of filtration, the more incomplete is the removal of
the bacteria. If the filter-bed is constructed as described
above, the rate of filtration will be about 18 gallons per hour,
and about 96 per cent of all the germs present will be removed,
together with the impurities present in suspension.

(4) The filter used at the Iowa Experiment Station was in
constant use for about three months, without having been
changed. At the end of this time it did as efficient work as
at any previous time. The length of time a filter-bed can be
used without being changed depends upon the purity of the
water to be filtered, and also upon which kind of filtration is
used, the continuous or the intermittent. The more impure
the water which has to be filtered, the oftener the filter-bed
should be changed. Whenever the rate of filtration is decreased
to such an extent as to make the process impracticable, the
filter-bed should be taken out and cleaned. If the water to be
filtered is of average purity, a change of the filtering-material
once every four months is ordinarily sufficient, no matter whether
continuous or intermittent filtration is used. A filter-bed may
do efficient work even a longer time than this. The same filter-
ing-material can be used again providing it is thoroughly washed
previous to replacing it in the filtering-can.

Kinds of Filtration The two kinds of filtration in use are
(x) Continuous, and (2) Intermittent.

By the continuous method of filtration the inflow of water
into the can is constant during night and day. The stream of
water admitted into the filter-can is sufficient to cause the
surface of the filter-bed to be covered with water all the time.
This method excludes all oxygen from the filter-bed, except
that which is in solution in the water.

During the process of filtration a slimy coat is deposited on
the fine sand. This seems to be the real agent absolutely
necessary in order to eliminate bacteria by a process of filtration.
A filter-bed without this slimy deposit on it simply takes out the
coarse organic and inorganic matter held in suspension, without

270 CHURNING AND WASHING BUTTER

removing the bacteria. If some bacteria are removed with
the matter held in suspension, others are carried along from the
filter-bed. Owing to this, a new filter-bed must be kept in
operation a few days before the filtered water can be considered
pure and ready for use. ‘The following table illustrates how the
germ-content of water is decreased as the process of filtration is
carried on during the first few days:

Filtered Unfiltered

Water, Tap-water,

Germs per | Germs per
Gc eG
No. 1. Taken when filter-bed was first used........ 20,000 107
No. 2. Taken when filter-bed had worked 1 day... . 860 118
No. 3. Taken when filter-bed had worked 3 days... 370 96
No. 4. Taken when filter-bed had worked 5 days... 48 54
No. 5. Taken when filter-bed had worked 7 days... 3 73
No. 6. Taken when filter-bed had worked 9 days... 5 89

It will be seen from the table that during the first three days
the filter-bed was in use the filtered water contained more
germs than the unfiltered. Good results were not obtained
until the seventh day. In order to be on the safe side it is
best to expose the filter-bed to continuous filtration for about
nine days before the water is used.

The slimy coat referred to above is formed by certain germs.
These germs then constitute the real agent of filtration. In
order that these micro-organisms may do efficient work oxygen
is essential. Well-water of average purity contains enough
oxygen in solution without employing an intermittent process of
filtration, and consequently for creamery purposes the con-
tinuous method of filtration is to be recommended.

Intermittent.—The intermittent process of filtration is used
where comparatively impure water is being purified, such as in
purifying water for large cities. If the continuous process
of filtration were employed in such instances, the filtered water
would not be free from germs, due to the fact that impure river-

METHODS OF PURIFYING WASH-WATER 271

water does not carry enough oxygen in solution to supply the
germs which form the real filtering agency.

If the intermittent process is used, the first water filtered after
the intervening period should not be used. During the inter-
mission, or during the time that the water is shut off, germs
develop and come through the filter-bed with the water that is
filtered.

Advantages of Purifying Wash-water for Butter.—The chief
advantage of purifying wash-water for butter is that the keeping
quality of the butter is improved, and if the proper skill and
care have been applied in the other steps of manufacture, a pure
sanitary product is obtained. The sanitary efficiency reached
by purifying the wash-water constitutes no small consideration.
Germs producing contagious diseases are thus prevented from
spreading.

CHAPTER XVIII
SALTING AND WORKING OF BUTTER

Objects of Salting.—(z) The chief object in salting butter
is to impart a desirable salty flavor. (2) Within limits, salt
improves the keeping quality of butter. (3) Salt facilitates the
removal of buttermilk.

Amount of Salt to Use to Produce Proper Flavor.—The proper
amount of salt to use in order to impart a desirable flavor depends
chiefly upon the market. Some consumers prefer a medium
high salt-content in butter; others, again, like butter which
contains very little salt. The English market demands rather
light-salted butter. In fact, this is the case with prac-
tically all European markets. American markets, as a rule,
demand a comparatively large amount of salt, as much as will
properly dissolve in the butter. Parisian markets and some
markets in southern Germany require no salt at all. The salt-
content of butter may vary between nothing and 4 per cent.
Butter containing as much as 4 per cent salt is, as a rule, too
highly salted, and part of the salt is usually present in an undis-
solved condition. Those who like good butter prefer the salt
thoroughly dissolved and well distributed.

The amount of salt to be added should be based upon the
least variable factor. Some creamerymen measure the amount
of salt according to the amount of cream in the churn. While
the box-churn and Mason butter-worker were being used, many
makers preferred to weigh the butter as it was transferred from
the churn to the worker. ‘The method mostly in use now and to
be recommended is to base the amount of salt upon the number
of pounds of fat. The amount of salt to use per pound of fat
varies, therefore, according to the conditions mentioned below,
and also according to local conditions. Usually from half an
ounce to one and a half ounces of salt per pound of butter-fat

272

EFFECT OF SALT UPON KEEPING QUALITIES 273

is most suitable. In whole-milk creameries the salt is often
estimated per hundredweight or per thousand pounds of milk.

To get the butter salted uniformly from day to day is very
important. A variation of 1 per cent to 2 per cent in the salt-
content can very easily be detected by the consumer, while
that much variation in any one of the other chief constituents
could not be readily noticed.

The conditions upon which the proper amount of salt depend
are: First, the amount and condition of moisture in the butter
at the time the salt is added. If there is a great deal of loose
moisture in the butter, more saltis necessary. This is due to the
fact that the saJt will go into solution in the water and be
expressed during working. Secondly, it depends upon the
amount of working the butter receives, and at what time the
bulk of working is done, after the salt has been added. If the
butter is medium firm, moisture in the form of brine is being
expressed during the working. Consequently, the more butter
is worked, up to a certain limit, the more brine is being expressed,
and the more salt should be added to the butter. Thirdly, it
depends upon the firmness of the butter, the size of the granules,
and the method of applying the salt. If the granules be inclined
to be soft and slushy more salt must be added than would other-
wise be necessary, as more will be carried off during the process of
working.

It is undoubtedly due to these facts that the salt-content
and the condition of salt in butter vary so much at the different
creameries; they even vary considerably from one churning
to another at the same creamery. If conditions are uniform in
the creamery from day to day, the amount of salt to add to
butter, and the amount of salt retained in the butter when
finished, will be comparatively uniform.

It was thought at one time that heavy salting covered defective
flavors in butter. Such is not the case; it really accentuates
them. Some of the large creameries make their second-grade
cream into sweet or unsalted butter.

Effect of Salt upon Keeping Qualities —wWithin certain
limits salt acts as an antiseptic and improves the keeping qual-

274. SALTING AND WORKING OF BUTTER

ities of butter; but there does not appear to be any advantage
to be gained from heavy salting. We submit the following short
tables in support of this view, the first made up from investiga-
tions by McKay and Larsen at the Iowa Station and the second
from investigations by Gray of the U. S. Department of Agri-
culture (Butter scored by McKay):

Ounces of SCORES
Nia Salt to
ee hon Pound When | AtEndof | At Endof | At End of
Butter Made One Month | Two Months ;Three Months
25 O. 92.0 85.0 75.0 65.0
26 0.5 93-5 87.5 85.0 78.0
Bepats 27 1.0 92.5 88.0 87.0 80.0
28 I.5 92.0 90.5 84.0 80.0
20 O°. 03.0 90.0 80.5 74.0
Eat ot { 30 I.0 94.0 89.0 86.0 87.0
SCORES
Per Cent

|
Num- of Before | Stored at — 10° F.| Stored at +10° F. | Stored at + 32° F.
ber Salt Storing #2 ==

Five Hight Five Eight Five Eight
Months | Months | Months | Months | Months | Months
Some jindividu al lots:
| { I.02 88 93 goz g2t 90 90 86
‘ 3.20 89 go 88 80% 86 85 84
2 { 1.10 QI 93 QIs 92 ort 89 88
2.87 Or 90% 87 go 87 88 87
2.00 ors o2t 89 89 89 QI 88
3 ‘ 2516 80% OI 89 go 883 89 84
{ 1.52 oid OI 883 got 88 88 82
4 3.28 | 89 89 85 873 85 86 80
Averajge of all ‘Lots in tlhe Experliment
Light
Salt 1.64 | 01.7 92.6 90.9 | 91.70 90.6 90.3 87.8
Heavy
Salt BoAVl || Ose 90.5 89.9 | 90.15 89.0 89.0 85.0

SALT FACILITATES THE REMOVAL OF BUTTERMILK 275

Each “ experiment ” in the first table includes samples of
butter from the same churning, salted at the different rates
indicated.

Each pair or lot of churnings reported in the second table
were from the same vat of cream.

The first table shows that salted butter keeps better than
unsalted butter. The second table shows that light salting is
just as effective for improving the keeping quality of butter as
heavy salting. In fact, in nearly all cases lightly salted butter
came out of storage, at the end of eight months, with a higher
score than butter that was heavily salted. This would be due
in part to the salt bringing out defects in flavor.

Salt Facilitates the Removal of Buttermilk.—That salt
facilitates the removal of buttermilk can easily be demon-
strated by observing the escape of buttermilk from the butter
immediately after the salt has been added and mixed with the
butter. The first effect of salt when added to the butter is to
precipitate the curd in the buttermilk. This precipitation is
greater when a large amount of salt is added than when only
a small amount-is added. ‘The precipitation of the casein in
the buttermilk sets free the remainder of the buttermilk con-
stituents; that is, when the casein is precipitated, the whey
part assumes a more fluid condition and escapes, and the butter
retains a portion of the curd. Owing to this action of the salt,
it is essential that the butter should be as completely washed as
possible, as otherwise it will retain an excessive amount of curd.
The butter acts in a manner somewhat similar to a filter in
removing a part of the curd from the other buttermilk con-
stituents.

Salt in Relation to Water in Butter.— Experiment has dem-
onstrated that pure fat is not a salt-dissolving substance. Owing
to this fact the only salt-dissolving substance in butter is water.
As water will hold only a certain amount of salt in solution, it
becomes evident that the amount of salt which can be properly
incorporated in butter depends upon the amount of moisture
present.

The amount of salt which water will hoia in solution at

276 SALTING AND WORKING OF BUTTER

different temperatures varies somewhat according to different
investigators. According to Gerlach! water will dissolve
35.94 per cent salt at 58° F. This is approximately the tem-
perature at which salt is worked into butter. Theoretically,
butter containing 15 per cent of water should be able to properly
dissolve 5.4 per cent of salt. Butter containing 13 per cent of
water should be able to properly dissolve .4.68 per cent of salt,
and butter containing 10 per cent of water should be able to dis-
solve properly 3.6 per cent of salt, etc. According to experiments

Fic. 102.—Action of salt solutions of different strength on the proteids of butter-
milk. (Bul. 263, Gen., N. Y.)

conducted at the Iowa Experiment Station the maximum per
cent of pure salt (NaCl) that could be properly dissolved in water
of butter containing 16.92 per cent of moisture, when worked 18
revolutions at Intervals during two hours, was 16.57 per cent.
When butter was worked the same number of revolutions at
intervals, and was allowed to dissolve only one hour, the amount
of pure salt (NaCl) that was dissolved in the water of the butter
containing 11.58 per cent moisture was 14.09 per cent. ‘This
undoubtedly will vary with different brands of salt.

1 Kemiker-Kalender, p. 219.

KIND AND CONDITION OF SALT 277

It will thus be seen that the property of water to take up
salt is seemingly lessened when the water is present in a state
of minute division, as it is in butter. In the first instance
quoted the butter completely dissolved about 2.7 per cent of pure
salt; and in the second instance it dissolved only about 2 per
cent during one hour.

From the foregoing it is evident that where butter contains a
high per cent of salt, the salt is not thoroughly dissolved.

Kind and Condition of Salt.—Salt for butter should be fine

Fic. 103.—Volumes of the same weight of salt of various brands.
(Bul. 74, Wis.)

and readily soluble, so that it will be completely dissolved and
incorporated when the working of the butter is completed. But
fineness alone does not determine solubility; some salts that do
not seem very fine are quite readily soluble, because the crystals
are somewhat flat and flaky and dissolve quite quickly. Again,
good dairy salt is clean and white in appearance. When it is
dissolved in a cylinder of water there should be no settlings and
nothing left floating on the surface of the water.

Some salt is chemically impure, one of the impurities being
magnesium chloride, which, when present to any extent, imparts
a bitter flavor to butter. Good butter salt is practically free

278 SALTING AND WORKING OF BUTTER

of this impurity. According to analysis of the best dairy salt
used in Denmark, the composition is as follows:!

Per Cent
Pure salt (sodium chloride (NaCl))........ 97-49
Magnesium chloride (MgClo)............. 18
Gypsum (calcium sulphate (CaSO.))...... 05
Social Sulphate) ys erserae es eee eee ae 2m
Waiter. uta See) ein ements DOF

I00..00

The purest American dairy salt has the following composition :?

Per Cent
Puresallig. tt ite eo ae 99.18
Mae mesiumachiloride see eee 505
Gypsies) cere Seiler Oe Ee 54
Caleiumychloncdes(CaClo)pe eee 19
Imsoluble matter se ee eee: eee ae 108
IMIGISEUUEE Ss Se ee an nee a eer a OED

TOO .0O

Good, moisture-free salt will contain 99 per cent or over of
sodium chloride (NaCl). Any substance other than this is an
impurity to the extent to which it occurs.

Salt readily absorbs odors and moisture. Hence it should
be kept in a clean dry place.

Gritty Butter.—" Gritty butter” is a familiar phrase used
by expert butter-scorers to indicate that part of the salt is
present in an undissolved condition. To most consumers this
condition of the salt in butter is objectionable. When properly
incorporated, salt should be present in the form of a solution
in the butter. The gritty condition of the salt in butter may be
due to (1) poor condition of the salt before it is added to the
butter; (2) adding so much salt that it cannot be dissolved by
the water in the butter. The maximum amount of salt that

1 Boggild, Maolkeribruget, Denmark.
2 Bul. No. 74, Wis., by F. W. Woll.

. MOTTLED BUTTER 279

butter will dissolve depends upon the amount of moisture present.
The maximum amount of moisture permissible in butter, accord-
ing to the Treasury ruling, is 16 per cent. The condition of the
water in butter prevents the water from being saturated with
salt during the comparatively short time allowed for salt to
dissolve during the manufacture of butter. (3) Insufficient
working. If the butter is not worked enough to distribute
the salt evenly, some portion of the butter will contain more
than the other portions. The portion that contains the excess

Fic. 104.—-Worcester salt. Fic 105—Diamond crystal salt.

Types of crystals of buttersalts.

of salt does not have enough moisture to dissolve the salt; while
if the salt had been evenly distributed in the butter, all the salt
would have been properly dissolved. When gritty butter is
caused by insufficient working, it usually mottles.

Mottled Butter.—Mottled butter is butter which is uneven
in color. This may be due to different causes. The most com-
mon cause, however, is failure to get the salt properly dissolved
and evenly distributed by the time the working of the butter is
completed.

280 SALTING AND WORKING OF -BUTTER

The causes and remedies for mottles are pretty thoroughly
understood by almost all up-to-date butter-makers. Twenty
or twenty-five years ago mottles constituted one of the leading
defects found in the creamery butter supplied to our markets.
Charles Y. Knight, then editor of Chicago Dairy Produce,
offered a series of prizes for the best methods of preventing
mottled butter, and many creamerymen entered the competition.
The result was that a lot of valuable information was obtained,
which resulted to a very large extent in preventing mottled but-
ter. Many theories have been advanced as to both the cause and
the remedy for mottles.

Long before creameries were established some farmers’
wives had mastered the art of butter-making to the extent that
they produced butter of a uniform quality free from mottles.
This was accomplished by their methods of working. Possibly
they had no knowledge of what actually caused mottles, but
they knew that if they worked the butter sufficiently to thor-
oughly incorporate the salt mottles would not appear in the fin-
ished butter.

Drs. Van Slyke and Hart say that if the proteids are thor-
oughly washed from the butter, mottles cannot be produced, no
matter how unevenly the salt is distributed. Complete removal
of the buttermilk by washing is one of the essentials in preventing
mottles in butter.

Storch made an extensive study of the causes of mottles
in butter. He claims that the water in butter is present in
two forms or conditions. There is the water which is con-
tained in the form of an extremely fine emulsion in the nitro-
genous material composing the film surrounding the fat globules;
and there is the water which is enclosed by the granules as they
form or is picked up later from the buttermilk or the wash-water,
and which is present in the finished butter in the form of larger
droplets, or a much coarser emulsion. The whitish, opaque
dapples, Storch claims, are due to the fine emulsion of water
in the nitrogenous material referred to, and the yellow, clearer
markings to the larger droplets of water picked up from the
buttermilk and wash-water.

MOTTLED BUTTER 281

Sammis and Lee repeated a portion of Storch’s investiga-
tion. They found that butter-fat, freed from casein by melting
and filtration, then emulsified with water and churned, pro-
duced typical mottles when the salt was not evenly distributed
throughout the mass. They thus produced mottles entirely
independent of the casein. Microscopic examination of such
butter showed similar results as in the case of Storch’s experi-
ment. In the portions which were lighter in color, the water
was present in the form of innumerable small droplets, while
in the portions that were darker, the droplets of water were much
larger. No counts nor measurements of the droplets were given.
These investigators emphasize the importance of thorough
working of the butter to prevent the mottled appearance.

The mottles caused by improper incorporation of salt assume
two different forms, viz., mottles proper, and wavy butter. As
has been mentioned before, the mottles result from undissolved
salt. Whenever there is undissolved granular salt present, the
moisture is attracted and the color deepened at that particular
place. In case the water has already been saturated with salt,
there is no danger of mottles, no matter how much gritty salt is
present.

Mottles do not affect the quality of butter, but the consuming
public desire uniformity in color. For this reason butter is
artificially colored during the winter months when cows are
on dry feed which is not conducive to the production of a yellow
color in the butter. Many people like the appearance of marble
cake; the same people would seriously object to marbled butter.

The salt which is placed on butter or mixed with it has an
affinity for water. ‘Therefore, the droplets of water are attracted
to the granules of salt. The result is that a certain portion of
the butter assumes a dark appearance, possibly somewhat
similar to the clouds appearing before a rainstorm; or, in other
words, mottles may be said to be caused by the uneven distribu-
tion of the water droplets.

It will be observed that the white streaks in butter contain
little or no salt. Professor O. F. Hunziker has done very
extensive work on this subject. The white opaque places in

282 SALTING AND WORKING OF BUTTER

mottled butter are caused by the localization of innumerable
very small water droplets.

There are a number of things that have a tendency to cause
mottles. In the early spring, when the cows are changed from
dry feed to grass, mottles are more prevalent than at any other

portion

Fic. 106.—Imperfect working, due to overloading churn, and causing a
of the butter to fall over the rolls without being worked, has a tendency to
cause mottles and uneven distribution of moisture,

season of the year. ‘This is due to the presence of an increased
per cent of the low-melting fats in butter. The butter has a
tendency to be slushy or soft and the granules of salt appear to
be imbedded in the butter and do not dissolve as readily.

This defect may be overcome by churning at a sufficiently
low temperature. The butter granules will then gather into a

MOTTLED BUTTER 283

firm enough mass to be efficiently worked. In small creameries
where only one or two churnings are to be made the butter can
be worked enough to mix the salt thoroughly throughout the
mass and permitted to stand for an hour, when the working may

Fic. 107.—Imperfect working, due to overloading churn, and causing a portion
of the butter to fall over the rolls without being worked, has a tendency to
cause mottles and uneven distribution of moisture,

be completed. This is a method that has been used by some
buttermakers for a great many years.

The system used in Denmark a number of years ago, when one
of the authors was visiting that country investigating creamery
conditions, was to mix the salt thoroughly with the butter on
the table worker; then cut the butter up into large rolls and place

284 SALTING AND WORKING OF BUTTER

it in a tank of water at a temperature of 60° F., and permit it to
stand there for two hours; then take the butter out and finish
working it. This had the effect of giving the entire mass of
butter a uniform temperature and it gave sufficient time to get
the salt quite thoroughly dissolved before completion of the final
working.

Quite a common cause of mottles, particularly in the summer
months, is the overloading of churns. Part of the butter
falls over the rolls instead of passing through them. Working
butter under these conditions will not, as a rule, produce either a
uniform color or a uniform distribution of moisture. Where the
rolls are out of alignment it also has a tendency to result in
uneven working and thus cause mottles.

Washing the butter with very cold water which chills the
surface of the granules also has a tendency to produce mottles.
Butter does not appear mottled when first taken from the churn.
On standing the more loosely held large water droplets run
together into larger aggregates and the portions of the butter
containing these fewer but larger droplets show deeper yellow in
color.

Prevention of Mottles in Butter.—To state the cause or causes
of a defect is often to suggest the remedy or remedies, in a
large measure. Unsalted butter is never mottled. This is, in
itself, very suggestive. It is well known to experienced
creamerymen, and has been taught in our dairy schools for
years, that butter will be neither mottled nor streaked if the
salt is thoroughly dissolved and the brine evenly distributed and
incorporated in fine particles or droplets in the butter by the
time we are through working it. There are several means which
further this end, and these may be briefly stated as follows:

Have the cream at the right temperature for churning.
The butter will then come in good condition. It will be reason-
ably firm and the buttermilk can be washed out of it thoroughly.

Have the wash-water at the right temperature, so that the
butter will be in good condition for working. It can then be
worked sufficiently to insure the end sought without injuring the
grain and body of the butter.

CURDY SPECKS IN BUTTER 285

See that the worker is in good condition. ‘The space between
the rolls, from end to end of the churn, should be the same;
they should be properly set and in perfect alignment, and there
should be no looseness in the bearings and no slipping. ‘The
rolls should be straight or without any warps in them, and so
set that the elevations on the one meet the grooves of the other.

Fic. 108.—Rolls out of alignment.

The same care must be taken with regard to the relation of the
roll to the shelf in single-roll churns.

Use a good quality of salt that will dissolve readily, and
distribute it in the butter as evenly as possible from end to
end of the churn.

Do not make too large a churning. This means overloading

eae

Fic. tog.—Rolls perfect. Fic. rro.—Rolls not meshing, causing
4 imperfect working.

the workers, and as a consequence part of the butter falls over
the rolls and is not worked.

If mottles develop in butter they can be eliminated by rework-
ing it. But this is a remedy that it should not be necessary
to apply very often.

Curdy Specks in Butter.—Curdy specks are not, properly
speaking, mottles. We should make a sharp distinction between

286 SALTING AND WORKING OF BUTTER

the two. Curdy specks, as the term implies, are small white
particles of curd throughout the butter that are visible to the
naked eye. Overripening of either the starter or the cream may,
and probably will, produce curd particles that will show in the
butter, especially if the cream is not strained into the churn
through a fine strainer. Avoid these faulty conditions; break
up and mix the starter thoroughly before putting it into the
cream; and strain the starter into the cream and the cream into
the churn.

To insure uniform salting it is advisable to bring the butter
up on the shelf and rolls, make a trench in it from end to end
of the churn—leaving both ends closed—and distribute the salt
evenly along the trench. Should the butter be in a very firm
condition a little water should be added to the salt. The
trench is then closed so as to cover the butter before the workers
are started.

As butter is worked it becomes an aggregation of butter
granules with the intervening spaces occupied by water, curd and
air. The more butter is worked the smaller the intervening
spaces. On the broken surfaces of worked butter and under the
microscope the water appears in the form of round droplets.
The less the butter is worked the larger the drops and the more
ragged the break or grain. The more the butter is worked the
smaller the droplets of water and the shorter the grain. If the
working of butter continues, air to the extent of ro per cent or
less by volume is incorporated.

When a piece of butter is torn from the partly worked mass
its broken surface is very irregular and shows large drops of
water, like tears. Upon squeezing, a shower of water falls out
of the butter. If packed in this condition the butter would leak.
As the working progresses the drops become smaller and smaller
and fewer can be squeezed out of a piece. The working has
produced the desired end when the broken surface sparkles with
small droplets of water like pinheads and only two or three drops
fall out upon squeezing. If packed at this stage the butter has a
beautiful grain and does not leak; but if worked beyond this
point the dreplets of water disappear, the grain becomes short

BRINE-SALTING 287

and the butter becomes greasy, air is incorporated, and the
color is light, dull and lusterless. Such butter is overworked
and keeps poorly.

The process of working grinds up the water in the butter into
smaller and smaller drops. In a leaky butter the water is
present in large drops; in a dry butter it is present in small but
numerous drops. Repeated working does not injure the grain so
long as drops of water can be seen on the torn surface. Logically
the working of butter should be continued until the butter is not
leaky and stopped before it is dry and sticky.

Brine-salting.— Brine-salting is not as a rule practiced in
creameries. It is too expensive a method of salting, and also
too laborious. By salting butter with brine it is hardly possible
to get in salt enough to suit the American butter markets, 2
per cent being about the maximum amount of salt that can be
incorporated by the brine method.

In some instances, brine-salting has been recommended. If
a light mild taste is desired, the brine method may give good
results. The greatest advantages of brine-salting are that
mottles in butter are practically avoided, and that the overrun
is usually increased a trifle. Especially is this so if the tempera-
ture of the brine is medium high when added to the butter. In
order to get enough salt (2 per cent) into the butter by the brine
method, it is necessary to churn it considerably in the brine and
to use two sets of brine. When brine is first added the butter
already contains considerable water. This water practically
has to be replaced by brine. This is difficult to do, especially if
the butter has been overchurned a trifle.

Churning the butter in the first brine will soon dilute the brine
to such an extent that it will impart but little saltiness to the
butter. For this reason this first brine should be removed and
another one added, and the butter churned again in this brine.
This last brine will have very little curd in it, and can be saved
until the following day and then used as the first brine. The
first brine may be used each day for soaking tubs.

It is essential to leave the brine on the butter for from five
to fifteen minutes. Churning excessively in the brine, espe-

288 SALTING AND WORKING OF BUTTER

cially if butter is medium soft, will cause too much water to be
incorporated in the butter. After the butter has been exposed
to the second brine the proper length of time, it should be drawn
off and the butter worked in the usual manner. Less working
is usually given to butter which has been salted by the brine
method. It should be worked enough to distribute the brine
evenly in the butter, and to bring the butter into a compact form.
If the butter salted by the brine method is not worked sufficiently,
it will become streaky in color after standing.

SALT TEST

Principle of the Test. -The reagent used is a solution of silver
nitrate (AgNO3), and the indicator is a solution of potassium
chromate (K2CrO4). The silver nitrate will combine with
either common salt (NaCl) or potassium chromate, but it has the
stronger affinity for salt. Hence, if we add a few drops of the
potassium chromate to a solution of common salt, and then
gradually add silver nitrate solution, the silver nitrate will com-
bine with the salt, forming white or colorless compounds. But
as soon as the salt is all used or taken up the silver nitrate com-
bines with the indicator, potassium chromate, producing a
brick-red compound.

Chemical Changes that Take Place.—First, as long as there is
free salt: AgNOs (silver nitrate)+-NaCl (common salt) =AgCl
(silver chloride)+-NaNO3 (sodium nitrate). No colored sub-
stances formed. Second, after all the salt has been acted upon—
2AgNO3+KeCrOsz (potassium chromate) = AgeCrOs, (silver chro-
mate, brick-red)-++-2KNOs3. Brick-red color produced.

Proportions in which Silver Nitrate and Salt Combine with
Each Other.—

Molecular weight of silver nitrate,
AgNO3=108+14+3X16=170

Molecular weight of common salt,
NaCl = 23 +35.5=58.5
Both are univalent.

SALT TEST 289

Hence,

58.5 grams salt combine with 170 grams silver nitrate.

x70

58.5

I gram salt combines with = 2.906 grams silver nitrate,

or

.oI gram salt combines with .02906 gram silver nitrate.

Features of Practical Salt Tests.—The same principle applies
to the various salt tests. In the different practical tests, com-
binations are worked out which enable us to read the per cent of
salt directly, without having to make any mathematical calcu-
lations.

The following combination enables us to read the per cent
of salt in butter directly:

(I) 29.06 (= 29.0) grams of silver nitrate in a solution made
up tO 1000 €.c.

(2) Burette for silver nitrate solution graduated in cubic
centimeters and tenths of a cubic centimeter.

(3) 10 grams of butter, with the salt solution from it made up
EOWZI5OIC.€:

(4) 25 c.c. of the salt solution, taken by means of a 25 c.c.
pipette, that is, a tenth of the salt solution, or a tenth of the salt
in the ro-gram sample of butter.

In 1000 c.c. of silver nitrate solution there are 29.06 grams of
silver nitrate.

In r c.c. of silver nitrate solution there is .o2906 gram silver
nitrate.

But we have already shown that .o2906 gram silver nitrate
reacts with .or gram of salt.

.OI gram salt in 25 c.c. salt solution=.1 gram salt in 250 c.c.
of salt solution, or in 10 grams butter, which is 1 per cent
of salt.

Hence, each cubic centimeter of the silver nitrate solution
required in making the test indicates 1.0 per cent of salt in
the butter.

290 SALTING AND WORKING OF BUTTER

To Make a Salt Test.—Either weigh out 10 grams of butter,
or take the residue from the ro grams of butter used in the mois-
ture test; and rinse thoroughly into a suitable flask, with a 250
c.c. mark on it, using distilled water at a temperature of 110°
to 120° F. for the purpose, and making up to 250 c.c. with dis:
tilled water at the same temperature. Mix thoroughly to dis-
solve all the salt.

25 c.c. of the salt solution are then transferred to a white
enamel cup, and to this are added 2 to 3 drops of indicator (a
ro per cent solution of potassium chromate) from a brown glass
dropping bottle.

The silver nitrate solution is then added from a burette, and
mixed as it is added, until a permanent, light brick-red color
appears.

Note the quantity of silver nitrate solution required to
make the test. If, for example, it requires 2.7 c.c. of silver
nitrate solution to make the test, this indicates that there is
2.7 per cent of salt in the butter; if it takes 3.8 c.c. of silver
nitrate solution, the per cent of salt in the butter is 3.8, etc.

Note.—If the salt solution were made up to too c.c. instead
of 250 c.c., we could take ro c.c. instead of 25 c.c. of this solution
to a test and read the per cent of salt direct, just as above. In
both cases we take a tenth of the solution or a tenth of the salt
in the 10-gram sample of butter.

Another combination that will read the per cent of salt
directly:

(x) A tenth normal (N/zo) solution of silver nitrate, that is,
17 grams of silver nitrate in 1000 C.c. of the solution. (The
molecular weight of silver nitrate being 170, there are 170 grams
in 1000 c.c. of a normal solution, and a tenth of this in a tenth
normal solution.)

(2) 10 grams of butter, the salt in it, being dissolved in
300 c.c. of water.

(3) By means of a 17.6 c.c. pipette we take 17.5 c.c. of the
salt solution to a test.

Each c.c. of silver nitrate solution required to make the test
indicates 1 per cent of salt in the butter.

WORKING OF BUTTER 291

Distilled water should be used in making the reagents and
for the test. The reagents should be kept in brown glass bottles
and out of strong light.

It is not advisable to make up more than about a month’s
supply of silver nitrate solution at a time.

WORKING OF BUTTER

Objects.—The objects of working butter are:

(1) To distribute the salt and brine evenly in the butter.
The number of revolutions in the churn necessary to accom-
plish this will vary somewhat according to the conditions of
the butter, and according to the kind of butter-workers employed.
Tf the butter is of medium firmness, about twelve revolutions in
the Victor Combined Churn will usually distribute the salt
properly, providing the working is well distributed over the
working period. It used to be, and is still, the practice in
creameries to add the salt while the butter is in a hard granular
condition, and then rotate the churn several times in slow gear
without putting the workers in gear. This is done in order to
mix the salt thoroughly without working. Then it is allowed
to stand for five or ten minutes, then worked about four revolu-
tions and allowed to stand a little while again, then the working
is completed by allowing the churn to revolve four or five times
more, or as many as is deemed necessary to bring the butter into
proper condition.

It has, however, been demonstrated that it is not advisable
to add the salt while the butter is in this hard granular form.
The butter should be united into larger irregular granules before
the salt is added. If the salt is added to the butter in a more
or less gathered condition, the workers should be put in gear at
once, for otherwise the salt will be scattered on the inside of the
churn. Butter can be worked three or four revolutions and
then allowed to stand until the salt is almost dissolved, at which
time the working can be completed by revolving the churn four
or five revolutions more. Some prefer to work a little more
than ten revolutions in order to be sure that the salt has been
evenly distributed.

292 SALTING AND WORKING OF BUTTER

If the Disbrow churn is being used, it is necessary to work
the butter a greater number of revolutions than that recom-
mended when the Victor churn is used. In the Victor churn
the butter is virtually worked twice at every revolution, while
in the Disbrow churn the butter is only worked once for about
three-quarters of a revolution. From sixteen to twenty revolu-
tions of the Disbrow churn usually mix the salt with the butter
properly. It is impossible to state exactly the number of revo-

8

Fic. r11.—Old-style table butter-worker.

lutions butter should be worked, as it varies according to different
conditions.

(2) Butter is worked in order to bring it into a compact form.
When butter is soft it usually gathers, but if it is present in the
firm granular condition, which condition results from churning
thin cream and washing the butter in cold water, it is more or
less difficult to get the little granules together. More working is
necessary when the butter is in such a condition.

(3) The working of butter also expresses an excessive amount

WORKING OF BUTTER 293

of buttermilk or water that may be present. By adding salt
and then working the butter, the excess of buttermilk is largely
eliminated. Especially is this so when the butter is ina medium
firm condition. Working is also effective in removing water
from the butter.

Moisture Tests of Butter.—1. Official Method. —‘‘ Weigh 1.5
to 2.5 grams of the sample into a flat-bottomed dish, having a
surface of at least 20 sq.cm., dry at the temperature of boiling
water and weigh at hourly intervals until the weight becomes
constant. The use of clean dry sand or asbestos is admissible.”

2. Rapid Method.—The moisture tests used in creameries
differ from the official method, mainly, in the speedier, less
refined scales used, and larger sample taken to a test, and in the
adoption of a higher temperature for driving the moisture off
more quickly. The results, when the work is carefully done, are
quite reliable. :

‘To Make a Test.—Obtain an average composite sample from
the churn, through scraping off the surface of the butter with a
ladle and taking samples from end to end of the churn by means
of a dry, warm spatula or spoon. In case of a tub take a core
with a trier, extending diagonally from top to bottom of the
package, and make up a composite sample from sections of this.
The composite sample jar should have a close cover.

Carefully warm the sample until the butter is of a pasty or
creamy consistency and mix well with a spatula.

Weigh to grams into a well-dried light aluminum cup about
25 in. in diameter. Place the cup on an asbestos sheet over a
low gas or alcohol-lamp flame, or hold over a low, direct flame.
Do not heat too rapidly. The heating process is complete when
foaming ceases and a light-brown color appears, and should not
be carried beyond this stage.

Allow the cup and contents to cool, then reweigh. The per-
centage loss in weight indicates the per cent of moisture. Most
scales read this direct.

CHAPTER XIX

PREPARING BUTTER FOR MARKET AND PREVENTION
OF MOLD

In the preparation of butter for market, care should be
exercised to see that only those woods which will not affect the
flavor of the butter are used in the package. From practical

Fic. 112.—Elgin style butter- Fic. 113.—Bradley
tub. butter-boxes.

experience and from various experiments it has been found

that ash and spruce are the most suitable woods in which to pack

butter to be delivered to the market. In the eastern markets a

decided preference is given to the 60-pound ash tub. Prior to

the use of this tub the old-style firkin was used. Possibly the
294

PREPARING BUTTER FOR MARKET 295

reason for the preference given to the 60-pound tub in the eastern
market lies in the fact that many dealers have so arranged their
refrigerators that they have a space in which the tub fits. Custom,
based upon long use of the 60-pound tub, has created such a
decided preference for butter packed in this manner that it
will sell in the eastern market at from half a cent to one cent
more a pound than if packed in a cubical box.

The Pacific Coast markets, on the other hand, have a decided

Folded.

Fic. 114.—The Eureka hand Fic. 115.—Butter cartons.
butter-printer.

preference for the cubical spruce box, and will pay a premium
for butter packed in that style.

If the butter is to be cut into prints, as is done by a
great many dealers at the present time, the cubical box has an
advantage over the tub. Butter so packed will cut into prints
with less waste.

In addition to spruce for the cubical box, Southern poplar
has been used quite extensively. A box of the following dimen-

296 PREPARING BUTTER FOR MARKET

sions holds 65 pounds of butter, and has given excellent satis-
faction for packing butter that is to be recut into prints. The
dimensions are, 143 by 133 by 10% inches, 76 inch ends and sides,
2 inch top and bottom.

For the Pacific Coast trade, boxes holding as much as go
pounds are used by some of our larger creameries. Boxes of
this size are not used to any extent in the eastern markets.

For packing butter on the farm, earthen jars give excellent
satisfaction, particularly if they are well glazed. Due to the
possibility of breakage, such jars are not used to any extent for
shipping butter. Earthern jars or crocks are very heavy and
easily broken during transportation.

For shipping in small packages of different sizes, the spruce
package is most commonly used. Some tubs manufactured for
this purpose hold 10, 20 and 30 pounds. The spruce tub is
also made in larger sizes, holding from 60 to 65 pounds.

While spruce will not flavor butter if the tub is rightly
prepared, the disadvantage of the spruce package is that it soils
very easily on the outside and gives the package an unsightly
appearance.

In Canada, New Zealand and Australia the cubical box is
used exclusively. These boxes are made to hold 56 pounds of
butter. Sometimes double covers are used. ,

Storing Butter in Creameries.—The temperature of the room
in which butter is stored should be as low as conditions will per-
mit. In local creameries a temperature of 40° or lower should
be maintained. In small creameries the butter is usually kept
at the creamery from three to six days. In some sections of the
country railroads carry refrigeration cars weekly; in others semi-
weekly. Hence, it is necessary to store butter at as low a tem-
perature as possible while it is waiting to be shipped. The
refrigerator in which the butter is kept at the creamery should be
as pure and dry as possible. Damp places are favorable to the
production of molds. Neither vegetables nor foods of other
kinds should be allowed in the refrigerator with butter, as they
are likely to impart foreign flavors to it.

All large creameries, the so-called centralizers, are equipped

COST OF MANUFACTURING BUTTER 297

with mechanical refrigeration for cooling purposes. Hence,
they are able to keep the storage room for butter at any tem-
perature desired. On the contrary, many of the small creameries
have to depend exclusively upon ice for refrigerating purposes.

Fic. 116.—Tub-fasteners; common tins.

In cases where ice is not available, water can be utilized for the
purpose of cooling. Water in the creamery can be forced through
galvanized iron tanks, which are properly placed in the butter
storage room cr refrigerator so as to allow as much cooling sur-

Fic. 117—Tub-fasteners: tin and tack combined.

face in the butter room as possible. ‘This is merely a makeshift
for ice and will not cool the room so effectively, but in the absence
of ice this is better than no cooling at all.

Cost of Manufacturing Butter.—This will depend upon the

Fic. 118.—Tub-fasteners; riveted.

volume of cream received and the kind of packages in which the
butter is to be packed for market. About fifteen years ago the
Iowa State Dairy Commissioner investigated this question, and
found the cost of manufacturing ranged from 1.2 cents to 6
cents per pound. The creamery where the cost ran up to 6

298 PREPARING BUTTER FOR MARKET

cents a pound only produced 30,000 pounds of butter per year.
The lowest cost of manufacturing was submitted by a co-opera-
tive creamery making nearly half a million pounds of butter
from whole milk exclusively. The approximate average cost of
making butter for the creameries in the State of Iowa at that
time was 2+ cents a pound. As labor, coal and all material used
in the manufacture of butter have greatly advanced, the cost at
the present time in the small creameries will exceed the above
figures.
In a medium-sized central plant the cost should not exceed
ume 2 cents a pound: ~“Whis does mar
| \ include the package. It includes
the cost of factory supplies, such
as salt, butter-coloring, milk for
starters, power, labor, refrigeration,
factory incidentals, factory main-
tenance and depreciation. The
cost of package will depend en-

Fic. 119.—Friday printer. Fic. 120.—Friday box.
(J. G. Cherry Co.).

tirely upon the kind of package used and the labor necessary to
pack. If the package used is the 60 or 65 pound tub or cubical
box, the cost of package and labor involved will not be very
great. If the butter is to be put up in fourth-pound or pound
prints, the cost will be much greater. At the present time, the
authors would place the cost, with the package included, at 3 to
3% cents per pound.

COST OF MANUFACTURING BUTTER 299

During the fall and winter, many creameries where the
milk supply is rather low print all their butter. Many of the
commission men will pay a premium of 1 cent a pound for butter

Fic. 121.—Miller hydraulic cutter for hard and frozen butter. (L. C. Sharp
Mfg. Co.).

so packed. The butter-maker has more time at this period
and should take advantage of it to put his butter up in neatly
packed prints. A creamery should have its own wrapper, and

Fic. 122.—Cross-section of a sewage-disposal tank. (Wallace’s Farmer.)

it should bear the name of the manufacturer. If the butter is
good, it will take but a short time for the consumer to become
familiar with this brand and a demand for it will eventually be .

300 PREPARING BUTTER FOR MARKET

created. It is essential, however, that we consider the cost of
printing the butter and the loss in printing. Some little waste of
butter accompanies the printing process. Butter to be printed
nicely should be firm but not hard, so that the print may assume
its proper shape. Butter should be worked to a point where it is
free from loose moisture; otherwise, the loss will be much heavier
in printing.

Treatment of Tubs and Boxes.—Investigations were made by
Rogers ! of the different treatments of tubs for the prevention

Waste Water from Cream Vats and Starter Can

Crearaery

re

Drain

\ Dix har
\
w
\ dischang p
(@)
et harge

Fic. 123.—Septic tank for creamery sewage disposal. (By Prof. J. Michels.)
The tank should be located in the ground with the top within a foot or
two of the surface. It may be constructed of planks. Brick, stone, or
concrete is preferable for durability. The tank should be built air-tight
except in two places, D and E.

of contamination by mold. Comparison was made of the fol-
lowing methods:

(1) Soaking the tubs overnight in cold water.

(2) Boiling five minutes in a saturated brine solution and
leaving in the brine overnight.

(3) Soaking overnight in a brine containing 9 per cent of
commercial formalin (which is a 4o per cent solution of formalde-
hyde).

(4) Coating the tubs on the inside with paraffin.

(5) Immersing the tubs for a few seconds in paraffin at a
temperature of 250° to 260° F.

Rogers comments upon the table giving results of his investi-
gations and makes some general observations, as follows: —

1 Bulletin 89, Bureau of Animal Husbandry, U. S. Dept. of Agriculture.

301

TREATMENT OF TUBS AND BOXES

WOOY 14nA4

(eurzuoyy ‘eS ng) -uvjd 100,47 A= ,7¢ 2389S “Alowreai v Jo uejg—tz1 OL]

‘

tc X él

7]

§3d019 z

WOCY ¥aMOd

SS SSS

Y3l0d

/@l Xb
WHO4.LV1d

NVid YOOTS

NY

I
Ino
ie
ie 606 X€2 jl 34.8, 2
m
y SDVYOLS G1090
NOOUY w,
(ep)
[
fe)
. vu
ae m
ib 28/1
m
l Z YaLLNO
| 2 WOOY 3YuOLS
| = We
| (ép)
w
| S
m
| 3ayvW

jee 38.8),

ONIAIZ03Y
IIA

dolds0

302 PREPARING BUTTER FOR MARKET

“Tt will be seen from this table that all of the untreated
tubs became moldy. Of the six tubs treated with hot brine,
one was badly molded, one was slightly molded and one had
mold on the outside. Of the six tubs soaked in the brine-
formaldehyde mixture, one was badly molded. None of the
tubs coated with paraffin showed any mold whatever, and the
same was true of those dipped in paraffin.

“To treat tubs by the brine-formaldehyde method or the
hot-brine method a vat should be made large enough to hold
submerged the tubs used in one day. The cost of either of these
two methods is insignificant as the bath may be used repeatedly.
The objections to these two methods, in addition to their inef-
ficiency, would probably be found in the discoloring of the wood
and, with the hot brine, in the excessive weight and swelling of
the tub.”

Paraffining of Tubs.—From the investigations made it would
seem that the most efficient method of treating tubs or boxes
for the prevention of mold is to paraffin them on the inside.

Before tubs are paraffined they should be thoroughly
steamed. In extreme cases, where tubs are very open, it may
be necessary to soak them, but only in such cases. Whether
soaked or not,.the tubs should be steamed just before parafhning
them. This swells and tightens the tub, and heats the wood and
opens its pores so that the paraffin will penetrate it sufficiently
and at the same time form a nice, smooth coating. ‘The par-
affin should be heated to a temperature of about 250° F. If
much below this it is apt to cause the coating to be thick and
patchy, and if much above it is likely to soak into the wood and
not form a proper coating. ‘The easiest way to heat the paraffin
in a creamery is to place a steam coil in the bottom of the
paraffin tank with a valve or dripcock on it to allow the escape
of condensed steam.

Where the work is done in a small way, the paraffin can be
applied in one of two ways—either by means of a brush or by
pouring some paraffin into the tub, rotating it to cover the whole
surface and then placing it mouth downward to drain the sur-
plus paraffin from it. But in a creamery of any size a suitable

PARAFFINING TUBS REDUCES LOSS FROM SHRINKAGE 303

apparatus for spraying the inside of the tub with paraffin
should be used.

As it only requires about 3 ounces of paraffin for a tub that
holds 60 to 65 pounds of butter the cost is not great, and the
work entailed in paraffining is no greater than that of either of
the other treatments mentioned.

Paraffin furnishes no food for molds; if there be any mold
organisms on the wood
they will probably be de-
stroyed to a very great
Extent sit not entirely.
either by the hot paraffin
spray or through the ex-
clusion of the air which
they require for growth;
and, even failing this,
the coating of paraffin
shuts them off from the
parchment paper and the
butter. Furthermore, as
paraffin is impervious to
water, the space between the liner and the tub remains filled
with water or brine which excludes the air and retards or pre-
vents the development of any molds that may be present.

Paraffining Tubs Reduces Loss from Shrinkage.—Another
strong inducement to paraffin tubs is the saving in shrinkage,
due to the prevention of the escape of moisture. In an experi-
ment made by Rogers, during his investigations, he found the
shrinkage, during a period of eight days in creamery storage
and in transit, on butter packed in paraffined tubs and in tubs
soaked in brine, respectively, to be as follows:

Zs

Fic. 125.—Tub paraffiner. (Creamery
Package Mfg. Co.).

| WEIGHT OF BUTTER
(Pounps) ;
Treatment of Tubs ovules ce | Shrinkage
Tubs when Packed | Aiter Eight | Pounds
| ie Days ||
Paratinedise: temo... 12 IST 756 Ii
Soaked ar wsitets sence bans 12 7663 750 es

304 PREPARING BUTTER FOR MARKET

Thus the saving in shrinkage, through paraffining, was
6 pounds on 12 tubs or half a pound per tub.

With unsoaked, paraffined tubs the tare should be marked
on the package. Such tubs may be as much as 2 pounds lighter
than soaked tubs.

Treatment of Parchment Paper.—As parchment paper is a
good medium for the growth of mold organisms and may harbor
the spores, though showing no growth of mold, it is quite as
important to treat it as to treat the tubs for the prevention of
mold. One method of treatment for parchment paper is to
soak it for at least ten minutes, before using, in a saturated
solution of brine at or near the boiling point. Russell and Hast-
ings! say, “‘ A most efficient way of treating paper, either for
tub liners or print wrappers, is to place same in boiling water for
a few minutes.” As formalin is very destructive of mold,
another very efficient treatment for parchment paper is to soak
it in cold brine or water containing formalin.

YEASTS AND MOLDS IN BUTTER

Bacteria are not the only micro-organisms found in milk and
its products. There are also yeasts and molds, the mold most
commonly found being Oidium (plural Oidia) lactis, or the
ordinary white mold which frequently appears on the surface
of sour milk or cream.

What may be desirable in connection with one dairy product
may be the reverse with regard to another. For instance,
_ Freudenreich and Marchel have shown that in the ripening of
certain Swiss and Belgian soft cheeses the common white mold
(Oidium lactis) plays a principal part. In these products its
presence is not only desirable but necessary.

On the other hand, it is found that where yeasts and molds
are present to any considerable extent in butter, it is not nearly
so likely to possess good keeping qualities as if they were not
present, even though its flavor when made be quite satisfactory.
They may be present in cream in quite large numbers, when it

1 Dairy Bacteriology.

YEASTS AND MOLDS IN BUTTER 305

arrives at the creamery, but if it be efficiently pasteurized and
kept from subsequent contamination, the mere fact of their
presence in the raw cream does not mean that the butter made
from this cream will be either defective in flavor, when made, or
lacking in keeping quality.

A study, by Bouska and Brown, of a large number of Baek:
ages of butter placed in cold storage showed that the number of
yeasts and molds present in butter, when made, is a fair cri-
terion from which to judge of its keeping quality. To put it
in another way, the number of yeasts and molds present in
butter, as it comes from the churn, is a good indication as to the
efficiency of pasteurization and the subsequent handling of the
cream to prevent re-contamination.

The laboratory of the American Association of Creamery
Butter Manufacturers has, for a number of years, made counts
of the number of yeasts and molds in samples of butter sent in
by its members, for this purpose. As a result of this work, and
the advice and assistance given, many of the creameries have so
improved their methods and equipment as to practically elim-
_ inate yeasts and molds from their butter, and make a product
possessing good flavor when fresh and good keeping qualities.

Where the number of yeasts and molds in butter is reduced
to ten or less per cubic centimeter—colonies counted without the
aid of a magnifying glass—this is regarded as excellent work;
and several of the creameries have reached this stage of effi-
ciency. A strong effort should be made by every creamery to
keep the number of yeasts and molds as low as possible, that is,
to thoroughly pasteurize the cream and prevent subsequent
contamination.

Whether or not the yeasts and molds present in butter are a
direct cause of deterioration is not definitely known, although
there are reasons for believing that this is not necessarily so.
Hastings found yeasts to be present in butter which won first
prize in a Wisconsin educational contest. The presence in
butter of yeasts and molds in large numbers usually means the
presence of other undesirable organisms in the cream, due to
one or more of the following causes:

306 PREPARING BUTTER FOR MARKET

(x) Inefficient pasteurization, the pasteurizing temperature
being too low or not maintained throughout the run, or some of
the cream at the beginning or end of a run not being pasteurized.

(2) Lack of thorough cleansing or sterilizing of the utensils
and conduits—pumps, vats, faucets, pipes, churns, etc.

(3) The use of a defective starter—one that has become
contaminated with yeasts, molds and undesirable bacteria.
Once this occurs it will propagate itself from day to day until
there is a change of mother-starter.

It must be remembered that although the pasteurizing may
be thoroughly done its good effects may be Jargely nullified
through subsequent contamination. Hence the final test of
the efficiency of pasteurization, in creamery work, should really

be the freedom of the butter from the ferments which cannot
fail to be eliminated by proper pasteurization, and the processes
that should accompany it. Another test of the thoroughness
of the pasteurization of milk or cream for butter-making pur-
poses is the Storch test, which is outlined in the chapter on
Pasteurization.

MOLD ON BUTTER

The development of mold on butter constitutes a defect that
causes large losses. Mold not only greatly mars the appearance
of a package of butter but affects its flavor as well. It develops
not only on the outside of butter but along the surfaces of any
crevices or pockets there may be and works its way into the
butter. Upon this point we quote Thom and Shaw of the U.S.
Department of Agriculture:! “In closed packages, wet or
damp cellars, or carelessly packed masses with cracks or fis-
sures in which moisture collects, mold may seriously injure the
appearance of butter packages or actually induce great changes
in the butter itself.’’ No score is given to moldy butter.

As to the character of butter that affords the most favorable
conditions for the growth and development of mold organisms,
if any be present, these same authorities say, “ Excess of curd

1“ Moldiness in Butter,” Journal of Agricultural Research, Vol. TIT, No. 4.

MOLD ON BUTTER 307

favors mold growth. Well-washed butter is less subject to
mold, Leaky butter—butter from which water or buttermilk
exudes and collects in the wrappings or the container—fur-
nishes the best conditions for the beginning of mold growth.
From these wet areas colonies may spread to the butter itself.”
These facts point to the necessity of churning at the right tem-
perature, washing the butter properly with water at the right
temperature and properly working it, so as to free the butter of
excess of curdy matter and buttermilk and make a butter that
is not porous but close, and in which the moisture is incorporated
in fine particles instead of larger droplets. They also show the
importance of packing butter closely so as to free it of air pockets
and fissures.

Conditions Favorable to the Growth of Molds.—Like all
other plants, large and small, molds require certain conditions
for growth. They differ from ordinary plants in that they do
not require light for their growth, but grow rather better in the
absence of light. ‘They require suitable food, but find this in or
on almost any organic matter, animal or vegetable, such as
bread, meat, leather, cheese, etc. They require moisture, and
hence develop rapidly in damp rooms and on damp surfaces.
They require a certain amount of air and will not grow in the
absence of it. As to temperature, while they develop most
rapidly in a reasonably warm atmosphere, many of them can
accommodate themselves to a wide range of temperature.

Discolorations.—The colors produced by molds range from
such light colors as orange-yellow to such dark colors as green, a
smudged or smoke color and black, according to the type of mold
present.

Propagation of Molds.—Molds reproduce themselves by
means of buds (conidia) and spores, and these float so freely
in the air that practically no exposed surface is entirely free of
them, and all they need for development is the suitable condi-
tions we have already outlined.

Sources of Mold on Butter.—The two most common sources
of mold on butter are the tubs or boxes in'’which it is packed
and the parchment paper. Wood that is green, sappy or damp

308 PKEPARING BUTTER FOR MARKET

is a good medium for the growth of mold; so also is parchment
paper, particularly if it be at all damp. Hence the tubs should
be made of well-seasoned wood of good quality, and both the
tubs and the parchment paper should be kept in a clean, dry
place. In the planing of the tub staves the planer should be
sufficiently sharp to insure a smooth surface.

CHAPTER XX

THE COMPOSITION OF BUTTER AND FACTORS THAT
INFLUENCE ITS CONTROL

Acts and Rulings as to Composition of Butter.—We have
only one Federal statute that deals specifically with the com-
position of butter, and this applies only to the District of
Columbia. This Act was approved March 2, 1895, and requires
that butter must contain 83 per cent of milk-fat, not more than
12 per cent of water and not more than 5 per cent of salt.

No attempt has been made to enforce the above statute, no
doubt due to the fact that creameries could not comply with the
same under the ordinary methods of butter-making.

Act of August 2, 1886, defines butter as follows:

“That for the purpose of this Act the word ‘ butter’ shall
be understood to mean the food product usually known as butter,
and which is made exclusively from milk or cream, or both,
with or without common salt, and with or without additional
coloring matter.’’

Act of May 9, 1902, known as the ‘‘adulterated”’ law, reads
as follows: ‘“‘Adulterated butter”? is hereby defined to mean a
grade of butter produced by mixing, reworking, rechurning in
milk or cream, refining, or in any way producing a uniform,
purified, or improved product from different lots or parcels of
melted or unmelted butter or butter-fat, in which any acid,
alkali, chemical, or any substance whatever is introduced or
used tor the purpose or with the effect of deodorizing or remov-
ing therefrom rancidity, or any butter-fat with which there is
mixed any substance foreign to butter as herein defined, with
intent or effect of cheapening in cost the product or any butter
in the manufacture or manipulation of which any process or

309

310 COMPOSITION OF BUTTER

material is used with intent or effect of causing the absorption
of abnormal quantities of water, milk, or cream; that “ process
butter’ or “renovated butter” is hereby defined to mean
butter which has been subjected to any process by which it is
melted, clarified or refined and made to resemble genuine butter,
always excepting ‘adulterated butter’ as defined by this
INGien

The ruling made by the Secretary of the Treasury, the Sec-
retary of Agriculture and the Secretary of Labor fixes the legal
standard of moisture in butter as 15.99 per cent. According to
TT this ruling, butter that contains 16
i j per cent would be classified as adul-
ye) terated butter. No allowance is
| 7 made for chemical errors in testing.
i While the chemists allow .2 per cent

for error, the Internal Revenue, in
enforcing this ruling, makes no such
allowance. In some districts the
courts have sustained the Internal
Revenue Department; in other dis-
tricts they have not. Some judges
have ruled that the Congress of the
United States is the only body that
has the power to fix definite stand-
ards for food products. No doubt
the Act of May 9, 1902, refers to
methods that were used at that time for the purpose of incor-
porating abnormal quantities of water.

Compounds for Increasing Yield of Butter.—The Internal
Revenue ruling is based entirely upon the “ adulterated ”
act. Prior to the adoption of the law of 1902 no attempt was
made by the government to enforce any regulations concerning
the manufacture of butter. At this early period various com-
pounds were used for increasing the yield of butter.

In 1893 the United States Department of Agriculture pub-
lished Farmer’s Bulletin No. 12, ‘‘ Nostrums for Increasing
Yield of Butter,” by Dr. H. W. Wiley, Chief of the Bureau of

ae
He

Fic. 126.—Ice-crusher.

NEED FOR REGULATIONS dll

Chemistry. The analyses published in this bulletin reveal the
fact that the compounds used increased the yield of butter.
Analyses reported by Dr. Wiley: .

Water Fat Ash (Salt) Casein
49.55 45-45 1134 3-36
2808 67.30 Sis .63

In 1900 experiments were carried on by Dr. J. B. Weems
and Prof. F. W. Bouska at the Iowa Experiment Station.
They tested out a number of compounds for increasing the yield
of butter and got the following results:

Water Fat Ash (Salt) Casein
Aki sAl 53-04 2.46 2.96

The second recipe was composed of the following ingredients:

PMMA CMO O US SUB Rs Barden yee ats aueals es 4 ounces

Ciummnvacaciapureye an eey tania es Sis), aes I ounce

aC CMC iets hii ae Sie al aig, eben ates 2 ounces 2 drachms
BEAUTE MDE OSI Macon vere. Esty eal Ma. 5 grains

Giving butter of the following composition:
Water Fat Casein Ash (Salt)
49.64 41.46 SCO 3.84

In addition to the above, samples of suspicious butter were

sent to the Station from a Chicago Commission House, which
showed,

Water Fat Casein Ash
59.61 At BU ie 72 7.36
42.76 44.92 Galo Tee

Need for Regulations.—From the above it would seem that
there was a necessity for some definite regulations concerning
the standard or composition of butter. Possibly the Internal
Revenue people, in endeavoring to enforce their ruling of 15.99
per cent, have been rather exacting in some cases where prosecu-
tions have been made.

In many cases, where the butter was found to slightly exceed

312 COMPOSITION OF BUTTER

the limit set by the Internal Revenue Department, creameries
were assessed 10 cents a pound tax on the butter, $50.00 a
month license, or $600.00 a year, and an additional 50 per cent
for not taking out a license. In some of these cases a few pounds
of butter were seized from a churning. Many creameries have
paid these assessments to avoid the notoriety of going into the
courts and defending their rights. Not only did the creamery
pay the above tax, but the dealer in butter was assessed $480.00
for a year’s license for handling so-called adulterated butter.
Creameries cannot sue the government for the refund of this
money. The only way they can get into the courts is to sue the
local agent. In many cases that have come up in the courts,
expert butter-makers have appeared as witnesses, some in —
behalf of the government and some in behalf of the creameries.
Some butter experts have made affidavits that the composition
of butter can be controlled and others have made affidavits that
it cannot be controlled. This diversity of opinion among so-
called experts no doubt has been due to lack of experience on
the part of some of the men testifying. No doubt all wit-
nesses appearing were honest in the testimony given.

Control of Moisture in Butter.—After spending over thirty
years in the butter business in various capacities and conducting
a vast amount of experimental work in an endeavor to control
the composition of butter the authors are convinced that the
moisture-content of butter cannot be completely controlled at
all times. Extensive investigational work was carried on at the
Iowa Experiment Station on this subject from igor to 1903.
The object of this work was not to incorporate water in butter
but to get butter to run uniform in composition throughout the
year. Prior to this investigational work the senior author had a
number of analyses made of the butter produced in some of the
best creameries during the entire year. In this investigation
the fat-content, the moisture-content and the salt-content were
found to vary greatly. In the winter months the moisture-
content might be as low as 1o per cent, and in the summer
months as high as 17 per cent. These creameries were not
making any effort to control the composition of their butter.

CONTROL OF MOISTURE IN BUTTER 313

They had their cream in such a condition that it would churn in
about forty-five minutes and the butter granules would be so
firm that the butter could be worked sufficiently to prevent
mottles and leaky butter.
Butter was churned nor-
mally to granules about
as large as wheat. A
number of conditions was
responsible for this wide
variation in the composi-
tion from season to season, such as washing with too cold
water in the winter months and churning at too high a tem-
perature in the sumumer months.

Feeding cows on dry feed during the winter months has an
effect upon the composition of fats. There are more of the
high-melting fats present; consequently, the butter has a
higher melting point.

In the early days of the creamery business practically all
butter was worked on the table worker. It was the custom of
many makers to work their butter twice. After having the
salt incorporated they would set it in the cooler for three or four
hours or leave ic until the next day. This had a tendency
to make butter with a lower moisture-content, as the second
working would invariably start a fresh flow of moisture from
the butter.

The invention of the combined churn and other modern
creamery machinery enabled the butter-maker more easily to
control the composition of the butter. The combined churn
has been a great benefit to the creamery industry. It keeps the
butter in a more sanitary condition and prevents flies and dirt
from coming in contact with it. The butter can be worked in
one working so that it will be free from mottles and in a con-
dition to be packed directly in sanitary packages. Hence it is
not surprising that the combined churn is being universally
adopted throughout the dairy world.

It is only reasonable to suppose that since the adoption of
the combined churn the moisture-content of butter would run

7)
@

THE) OS#ORN MEG CO.CLEV.o

Fic. 127.—Rubber mop.

314 COMPOSITION OF BUTTER

somewhat higher than under the old method of working on the
table worker, due to the variation of temperature, which affected
the hardness of the butter when it received its second working.

Many of the earlier analyses were of butter that had been
manufactured under the earlier conditions outlined here.
Hence, it is not surprising that the composition varied greatly.

The composition of butter may vary greatly in different
localities. There are two instances that have come under the
observation of one of the authors; these will be designated as
Creamery A and Creamery B. Both creameries were located
in the northern part of Iowa.

Creamery A in the latter part of the month of May, 1908,
sent word to the lowa Experiment Station that they were
unable to keep the moisture-content of their butter below —
16 per cent. Hence, they naturally feared that their butter
would be seized by the Internal Revenue authorities, and that
they would be prosecuted for making adulterated butter. They
maintained they had had some butter experts there to help them
out but that they had failed to accomplish the desired results.

The authorities of the Iowa Experiment Station sent them a
graduate of the school, Mr. C. L. Mitchel, who had had a great
deal of practical experience before going to college. He found
that the butter-maker was churning at as low a temperature as
44° F., and was trying every method that he knew of to hold the
moisture below 15.99 per cent, the limit fixed by the Internal
Revenue Department. Mr. Mitchel churned out two churnings
at the same temperature and got a moisture-content of between
17 and 18 per cent. He therefore changed his methods and
raised the temperature to 52° F., and after completing his
churning worked the butter through the rolls several times to
expel a portion of the moisture before applying the salt. This
method worked out very successfully. The rolls expelled con-
siderable moisture before the salt was applied. As soon as the
salt was applied it attracted the moisture and the result was
that sufficient moisture was easily expelled from the butter to
enable him to make butter that contained moisture below the
required standard. This method is now practiced in some of the

ANALYSES OF COMMERCIAL BUTTER 315

large creameries, especially in the early spring months when the
grass is inclined to be slushy and wet. Butter of this character
has a tendency, however, to be slightly greasy or overworked.

Creamery B was situated in the northwestern part of the state.
Mr. J. C. Joslyn, who is generally recognized as one of our lead-
ing butter authorities, had charge of this plant. Prior to the
experience that Mr. Joslyn had with this high moisture he was
under the impression that if any butter contained more than
16 per cent moisture, this excess moisture was intentionally
worked in by the maker. One day, however, he had a churning
where the method as far as he knew was similar to that he had
been pursuing to make the best butter. This particular churning
of butter, upon testing, showed a moisture-content of 18 per cent.
The peculiar thing about this butter was that the moisture was
so incorporated that he was unable to expel it, even by reworking
the butter. The authors have heard of only a few instances of
this kind. The only way whereby Mr. Joslyn succeeded in
reducing the moisture was to put the butter in a cooler for two
days and then break it up into small pieces and rework it. In
this way he was able to reduce the moisture below the point
permitted by the government regulation.

One of the authors, in visiting the Experiment Station at
Copenhagen, was informed by Dr. Holmes, Dr. Storch’s first
assistant, that they had found in their educational scoring
contest in Denmark a few firkins of butter that ran as high as
18 per cent moisture and were perfect in body and general
appearance. They were unable to give any explanation for the
occasional production of a churning of this kind. ‘The finding of
excessive moisture in butter is not a new experience in the butter
business.

ANALYSES OF COMMERCIAL BUTTER PUBLISHED BETWEEN
THIRTY AND FORTY YEARS AGO

Blyth says:

“There is no standard followed or fixed with regard to the
percentage of water. In those cases in which the fat is below
80 per cent, the deficiency of fat is usually from excess of water,

316 COMPOSITION OF BUTTER

and seeing the variable quantity of water found in butter, it
is wisest not to certify on the grounds of water alone unless there
is sufficient to lower the percentage of fat below 80 per cent.

“ At the Bath Police Court (January, 1879), a dairyman had
been summoned for selling butter, the proximate analysis of which
showed a considerable addition of water. An appeal to the
Somerset House elicited the following certificate:

‘““We hereby certify that we have analyzed the butter and
declare the result of our analysis to be as follows:

Per Cent
Waters). (Srisida s0t ear SMR te eae an 2327
Bubberstaeis See FLV ieee, Perks een enna 74.69
Sati oe Es Se Ped he cana pee ae 78
O10 Ra RAR a Re MRA Ome WA DA RSG 2 1.26

“The result of our analyses of numerous samples of ordinary
commercial butter obtained from different parts of the country,
including the south of England, shows that the portion of water
is very variable and that it occasionally amounts to as much as
Ig per cent.”

James Bell obtained, for 117 samples of butter collected in
various parts of the kingdom, and asserted by him to be genuine,
proportions of water varying from 4.15 to 20.75 per cent.

Lewkowitsch in his work says:

“The proportion of water in butter should not exceed 16
per cemua

He gives the following table to illustrate the amount of
water present in butter on the English market:

Samples Containing
Nic. oF Per Cent of Water
: Above
Samples Observer
; From From 16
Examined
Ir to 14 to to 16
English and foreign. 560 83.8 04.2 9 Vieth
nelishe eae 143 70.7 85.4 7 H. D. Richmond
Horelcnee ener 417 88.2 07.2 I.0 H. D. Richmond

ANALYSES OF COMMERCIAL BUTTER 317

The above analyses reveal the fact that the moisture-content
of butter was as high and as variable as at the present time.
Even at that early date Blyth fixed 80 per cent as the minimum
fat-content for butter. The composition of butter in the early
days was more variable than it is at the present time. This is
to be expected from the fact that more efficient machinery and
methods are now used for controlling the temperatures, and that
butter-makers have a better understanding of the effect of tem-
perature on the control of moisture. Butter made at the present
time will undoubtedly compare very favorably with butter
made in earlier years.

Standards in Different Countries.—Most of the European
countries have limited regulations to specifying the moisture-
content of butter rather than the fat-content. The Inter-
national Dairy Congress held in Brussels in 1910 passed resolu-
tions favoring 18 per cent moisture as the maximum amount.
England has a 16 per cent moisture regulation for butter, and
24 per cent for blended butter. France has an 18 per cent regu-
lation and Belgium an 18 per cent regulation for moisture.
Denmark has a 16 per cent regulation for export and 20 per cent
for home consumption. Canada has a 16 per cent regulation.
Germany has an 18 per cent regulation for moisture for unsalted
butter; for salted butter her standard requires 80 per cent fat
and not more than 16 per cent moisture. Italy has an 82 per
cent fat regulation. Queensland has a 16 per cent moisture regu-
lation and 80 per cent fat. Victoria has an 80 per cent fat and
16 per cent moisture regulation.

Possibly the reason that some of the European countries have
adopted a moisture rather than a fat standard is that it is much
easier to make a moisture determination than a fat determina-
tion, as in dealing with moisture we are only dealing with one
agent, and with the fat determination we have three agents
to deal with, the salt, casein and moisture. A 16 per cent
moisture and an 80 per cent fat standard for butter would be
practically the same. Taking 3 per cent for salt and 1 per cent
for casein, this would leave 80 per cent fat, providing the moisture .
were carried to the limit, which is not a wise or a safe proposition.

318 COMPOSITION OF BUTTER

The consumer in purchasing butter buys it for its food value
or fat-content. Therefore, it is only reasonable that the cream-
erymen should be willing to have all their butter contain at
least 80 per cent fat. No doubt the reason so many of the
European countries have recommended a high moisture-content
of 18 per cent is that they use less salt in their butter. An 18
per cent moisture, according to their methods of salting, would
be about the same as 16 per cent in this country.

The authors are very much in favor of a definite standard
for butter, the minimum fat-content being 80 per cent and
the moisture-content 16 per cent. Some tolerance or allow-
ance seems necessary, as butter may vary in moisture, especially
from one end of the churn to the other, as much as 1 or 13 per cent.

Factors that Aid in Moisture Control.—The two principal
factors that aid in the control of moisture in butter are the per
cent of fat in the cream and the temperature at which the cream
is churned. Where the fat runs uniform and the cream contains
a high per cent of fat, the moisture can be controlled quite
accurately by observing the size of the granule and controlling
the temperature of churning.

Bulletin No. ro1 of the lowa Experiment Station, page 167,
gives the results of some churnings made by the senior author in a
demonstration to short-course students during the month of
January, 1908. This butter was worked in a Victory churn.
The cream for these particular churnings was separated from
whole milk by the Randall Creamery Company, Randall, Iowa,
and shipped to the Iowa Experiment Station. Upon arrival
the cream tested from 42 to 45 per cent. After reducing with a
starter, holding the cream over night and churning the next
morning, the results given in the accompanying table were
obtained.

Butter proper contains, besides the water, fat, protein and
curd, a small amount of milk-sugar, .35 per cent, and ash from
.14 to .16 per cent. A butter-maker, to be successful, must
study his conditions from day to day and from week to week;
otherwise, during a rainy season when the grass becomes slushy,
the moisture-content is likely to vary or exceed the limit, even

FACTORS THAT AID IN MOISTURE CONTROL 319

Tem-
mnetoe Per | But- Paes aot pera- | Rey. | Amt. Ra Per
Date | Churn agen Cent | ter- Seal esale ture for of One Cent
Test Fat of Salt |Butter Water

ture ;Temp. Tun

Spray
Dec. 31] Vic. WABZ || Beas AI2 58 59 54 14 Rue |) Qe 15.8
Jan 3 Vic. 1343 | 36.5 490 58 59 53 13 600 | 22.5 | 15.9
Jan. 6) Vic. | 1435 | 34.5 | 495 57 58 54 13 609 | 23 15.3
Jan. 7| Vic. | 1204 | 33.5 403 57 58 54 13 499 | 23 15.9
Jan. 10] Vic. 910 | 33 300 57 58 58 18 B75 | BA iB69

|

though the same regulations have been observed as at other
times. Makers have been heard to say that they could control
the moisture-content of butter to within two or three hundredths
of the limit. Serious doubts may be entertained as to the cor-
rectness of such a statement.

Not very long ago a butter-maker called at the office of the
American Association of Creamery Butter Manufacturers and
proclaimed that he was churning in such a way that his moisture-
content would not vary more than two or three hundredths of a
per cent from day to day. He was asked to send a sample of his
butter to the Association laboratory, and it was found to have a
moisture-content of nearly 17 per cent. The moisture in the
samples he sent in varied 2 per cent, or ranged from 15 to 17
per cent. ;

Different methods are used for controlling moisture. Some
make a moisture test when the working of the butter is about
half finished. If it is found that the butter runs low in moisture
they add to the churn the amount of water they wish to incor-
porate and continue working until the butter takes up the water
added to it in the churn. On the contrary, if they find the
moisture is too high they fasten the churn door so that moisture
will escape and continue to work the butter until it contains the
right per cent of moisture.

Other companies that manufacture enormous quantities of
butter never work butter in water. They endeavor to control
the moisture entirely through their methods of churning. They
are not, however, trying to crowd the limit in moisture.

With thick cream, or cream containing a low per cent of

320 COMPOSITION OF BUTTER

fat, it is a more difficult problem approximately to control the
composition of butter. Churning cream at a high temperature
will invariably result in a high moisture-content and will also
result in an extreme loss of fat in the buttermilk.

In churning cream of medium-high fat-content, it is advisable
to fill the churn only about half full, to churn at such a low tem-
perature that the butter will gather in about forty-five to fifty
minutes, and to churn the butter to granules about as large as
peas. A small variation in the components of butter affects the
quality very little, provided the butter has been properly made
and the components properly incorporated. In the same cream-
ery the composition of butter varies according to the season of
the year, from day to day or even from churning to churning.
According to the present methods of manufacturing, water and
salt are the components most likely to vary. Casein will vary very
little if the butter is efficiently washed and churned in a condi-
tion in which it will gather firm. Normally, casein is estimated
at 1 per cent, occasionally it has been found to run as high as
4 per cent. It rarely exceeds 2 per cent, and seldom falls as
low as 7% of 1 per cent. A high curd-content will show itself in
the butter in the form of milky brine or in the form of white
specks. If there is less than 2 per cent present, the brine will
not be affected.

One of our large creameries had an average casein con-
tent of .65 fora year. This was due to their method of washing
their butter a number of times. An excessive amount of casein
in butter is supposed to affect its keeping qualities.

Curd and milk-sugar are incorporated from the milk into
the butter during the churning. In the manufacture of butter
for storage, these substances should be excluded from the butter
as thoroughly as possible. Milk-sugar and albuminoids consti-
tute the chief foods for bacterial growth. As deterioration of
butter has been demonstrated to be due chiefly to the action
of micro-organisms it becomes essential to restrain their growth
as much as possible by excluding the food necessary for their
growth.

The average salt-content of butter is about 23 per cent;

FACTORS THAT AID IN MOISTURE CONTROL 321

it may vary from 1 to 4 per cent. The amount of salt properly
dissolved in butter depends upon the amount of water present.
The first important step in controlling the salt-content is to have
a reasonable control of the water-content of the butter. If
there is 16 per cent of water present in butter it is desirable to
incorporate as much salt as the water will dissolve within the
time usually allotted for that purpose. This amount of salt
suits most of the American butter markets.

The authors have analyzed commercial butter containing as
high as 8 per cent salt, the major portion of this being present in
an undissolved condition. Such butter is called gritty and is
objected to by the consumer. Salt acts as a preservative to some
extent and adds flavor to butter provided it is in good condition.
It has been said that the addition of salt has some effect upon the

body of butter.

_ Richmond asserts that salted butter loses more water on
standing than unsalted butter. Undoubtedly this is due to the
fact that the salt added to butter has an affinity for water and
the drops of water in salted butter are much larger; conse-
quently, unless the butter is thoroughly worked so as to break
up the drops of water into smaller drops, this will have a ten-
dency to cause what is known to the trade as leaky butter. It is
much more difficult to expel moisture from unsalted butter;
consequently, a great deal of unsalted butter has been seized by
the Internal Revenue officials due to the fact that it exceeded
the prescriked moisture limit set by the Internal Revenue
Department.

Unsalted butter, if exposed to medium-high temperatures,
deteriorates quite rapidly, and frequently has a pronounced
cheesy flavor. If it is kept at an extremely low temperature it
keeps well in storage. Creameries have been known to put up
their butter in an unsalted condition in the summer and put it
down to zero or below; in the winter they took it out, salted
it, and worked it up in prints as fresh butter for their winter
trade.

Excessive moisture in butter causes it to become dull or
iusterless in color. Butter that has a very dry appearance and is

322 COMPOSITION OF BUTTER

dull in color is invariably high in moisture. Overworking butter
or working it to a condition where an additional amount of air is
incorporated not only affects the color but gives the butter, when
placed in storage, a tendency to deteriorate quite rapidly and
become fishy.

The temperature of the wash-water has a bearing upon the
quality of butter. Water that is too high in temperature has a
tendency to soften the granules and thus cause them to absorb
an excessive amount of moisture. When the temperature of
cream is too high for churning, an excessive amount of butter-
milk is incorporated in the butter and the latter will not keep well
either in storage or out of storage. The more butter is worked
in the presence of water the more water it will take up.

Making butter from pasteurized cream has a tendency to
cause a greater loss of fat in the buttermilk.

CHAPTER XXI

DEFECTS FOUND IN BUTTER

SOME OF THE CAUSES AND THEIR PREVENTION

In the scoring of butter, 45 points are allowed for flavor,
25 for body, 15 for color, 1o for salt and 5 for package. This is
the score that is generally recognized in this country. Some
expert judges have used the score of 50 for flavor, in which case
5 are taken off for body, allowing 20 instead of 25. We can,
_ therefore, see that flavor is the most important factor in deter-
mining the quality of butter. The other defects found in butter
are mechanical defects caused by the process of manufacturing.
Undesirable flavors affect the selling price of butter more than
anything else.

Flat or Insipid Flavor.—Butter that lacks flavor is sometimes
termed by judges insipid, or flat. Various terms are used in
describing the flavor of butter. For good butter, such terms
are used as rich, creamy, aromatic. Butter may be rich in flavor
without having a pronounced aroma. This kind of butter has
a pleasant palate flavor. A flat or insipid taste may be due to
several causes, such as excessive washing and making butter
from unripened cream. If cream is pasteurized and a large per
cent of good starter is used, the flat flavor, above described, will
be overcome.

Butter made from cream of which the flavor is not clean will
score much higher if it is unsalted. For this reason, many
creameries manufacture their second-grade cream into butter
without the use of salt and make what is known to the trade as
“sweet butter.” The theory was advanced some years ago, by
writers on butter, that heavy salting covered up many defects.
Various investigations have demonstrated that this is not true.

323

324 DEFECTS FOUND IN BUTTER

Heavy salting has a tendency to bring out the latent flavors.
Butter made during the winter months is usually deficient in
flavor, especially where the cream has not been ripened. Hence,
flat-flavored butter is more prevalent in winter than during the
summer months.

Stable Flavors.—Stale and stable flavors are also quite
prevalent during the winter months. Many of the organisms
that gain access to milk and cream during the winter months
come from the stables and are putrefactive organisms that
decompose the casein, such as Proteus vulgaris, B. subtilis and
B. fluorescens. These organisms are usually found in milk
produced in stables and gain entrance from many sources,
such as manure, feed, water, dirty utensils and the air; it is
therefore practically impossible to exclude them. There are
also a number of other organisms that decompose the casein.
Keeping milk too long in a poorly ventilated cow-stable has a
tendency to cause it to take up flavors by absorption. Where
cows are milked in warm basement stables, poorly ventilated,
undesirable fermentation is apt to predominate in souring the
cream without the use of a starter. Two of the principal causes,
however, of poor quality in cream are failure thoroughly to wash
and scald all dairy utensils that come in contact with milk or
cream, especially separators, and failure quickly to cool the
cream to a low temperature to check fermentation.

Flavors Acquired by Absorption.—The most common of these
are house flavors, cellar flavors and vegetable flavors. These
flavors are all taken up by absorption by the cream. While
pasteurization will not remove all these flavors, it has the effect
of removing some of them. Pasteurization to a high tempera-
ture, 180° to 185° F. under the flash method, or 170° F. under the
holding method, and the use of a good starter, will improve the
flavor of butter made from such cream. House, cellar and food
flavors are at times so pronounced in butter that a butter judge
can give a very accurate account of where the cream was kept
by merely examining the butter.

Cheesy Flavor.—Cheesy flavor is a defect that is sometimes
found in butter of low-scoring quality that has been kept for a

SOME OF THE CAUSES AND THEIR PREVENTION 325

long time at high temperatures. When butter is deteriorating
very rapidly in quality it usually reaches the stage where it has a
pronounced cheesy flavor, which later on changes to what might
be described as a turpentine flavor. Butter of this character will
usually sell in the markets as “‘ Seconds.”’ Cheesy flavor is said
to be due to decomposition of the curdy matter in butter.

Sour Flavor.—Sour flavor is sometimes caused by over-
ripening the cream at the creamery. The authors have seen good
cream from whole milk overripened to such an extent that it
produced sour-flavored butter. The churning of cream with
high acidity, without reducing this acidity, will produce sour
butter. Butter judges sometimes describe a sour, disagree-
able flavor as a dish-rag flavor, because the odor accom-

panying it is very much like that given off by an unwashed dish
cloth. The use of unclean cloths for cleansing dairy utensils
usually means the transmission of undesirable flavors to milk
and cream. For washing utensils a brush is much preferable to a
cloth.

Some creameries that are producing the best butter from
shipped cream have a set rule that all cream cans must be thor-
oughly cleansed and sterilized before being returned to patrons.

Harding and Ayers both report that they were able to produce
good milk in stables where manure was plentiful, and cobwebs
were hanging from the ceiling, by sterilizing all dairy utensils
that came in contact with the milk or cream.

Eckles, when connected with the Iowa Experiment Station,
isolated Bacillus coli aerogenes, added it to pasteurized skim-
milk and made a starter, and added the same to sweet cream
for the purpose of ripening or souring it to determine the injurious
effect it would have upon the flavor of butter. The quality of
the butter produced was not seriously affected by this starter.
One of the authors had the privilege of scoring this butter, and, in
his judgment, it was good commercial butter, though not as
pronounced in flavor as butter made from cream ripened by a
culture starter.

Faulty Factory Conditions.—Bad flavors found in milk, cream
and butter are sometimes due to conditions prevailing in the

326 DEFECTS FOUND IN BUTTER

factories, such as unsanitary pumps and leaky cream vats or
coils. Unsanitary pumps have been the means of transmitting
many undesirable flavors to both milk and cream.

Ayers states that he has investigated the causes of undesirable
flavors in milk at milk plants, and has found the trouble to be due
in some cases to unsanitary pumps. An instance of this kind
came up in one of the best creameries in Iowa, a whole-milk
plant that had been noted for the excellent quality of the butter
it was producing. A cut of several cents a pound in the price of
the butter had been made, due to a very disagreeable flavor that
it had shown. The maker, who was above the average in intel-
ligence, was unable to locate the cause of the peculiar flavor that
was developing in his cream and butter. He asked the State
Dairy Commissioner to send one of his best men to help them
locate their trouble. The state inspector examined the creamery
and found everything in apparently a good condition. He
weighed the milk himself, and found the quality of the milk
received was exceptionally good. As soon as the pump was
started and the milk was pumped up to the heating tank and
from there passed into the separator, the first cream passing
from the separator showed the peculiar flavor that was found
in the butter. From this it was concluded that the trouble was
in the pump. The pump was taken apart, heated in the furnace
for some time and thoroughly cleansed, then put together again.
When the pump and separator were started again, the cream was
fine. The maker’s trouble was that he had not been in the
habit of taking the pump apart for cleaning but had merely
pumped water through it and steamed it. The hot steam evi-
dently condensed, covering up undesirable organisms and pro-
tecting them from the heat of the steam. From this will be
seen the importance of sanitary pipes and the use of a pump’
that can be thoroughly cleansed every time it is used, for either
cream or milk.

Leaky vats and coils in creameries are sometimes the cause
of bad flavors. A leaky vat will produce in cream a pungent,
disagreeable flavor that is somewhat different from the flavor
produced by almost anything else, and this will be transmitted

SOME OF THE CAUSES AND THEIR PREVENTION Be

to the butter. One of the authors, when scoring educational
butter, stated in writing to one of the exhibitors that the butter
had a peculiar flavor that was undoubtedly caused by one of his
cream vats leaking. Upon examination he found this to be the
case.

Feed Flavors.—Some feeds have a pronounced effect upon
the flavor of cream and butter; some of these are desirable and
others undesirable. The flavor of turnip tops or turnips affects
the sale of butter; but its effect can be largely overcome if these
are fed after milking. Where cows have access to leeks, wild
onions or garlic, very undesirable flavors will be produced in
milk, cream and butter. Garlic and wild onions produce such a
disagreeable, pungent flavor in butter that some creameries
have refused to buy cream so flavored, while other creameries
make a difference of 10 cents a pound in the price of the milk-fat.

Ayers and Johnson, in Farmer’s Bulletin No. 610, give the
results of their investigation on this subject.

For the Removal of Garlic or Onion Flavors.—It is a well-
known fact that heating milk or cream to a high temperature
will eliminate, in whole or in part, flavors of a volatile nature. If
we combine with this the aeration of cream, through forcing or
blowing air into it under pressure, this will further aid in the
removal of such flavors.

In Farmer’s Bulletin 608 of the U. S. Department of Agri-
culture is given an outline of an experiment for the removal of
onion or garlic flavor. In this experiment a vertical, cylinder-
shaped, jacketed tank, with an agitator in it, was used for hold-
ing and heating the milk or cream, and above this was placed a
smaller tank with a perforated bottom. The milk or cream was
heated, the temperature being maintained at 145° F. or above.
Air was then blown into the milk or cream through a pipe
extending almost to the bottom of the tank; and at the same
time the milk or cream was constantly pumped into the upper
tank with the perforated bottom, from which it ran back, in
fine streams, which reduced the foam on the top of the milk or
cream in the larger tank. .

It was fouud in this experiment that the higher the tem-

328 DEFECTS FOUND IN BUTTER

perature to which the milk or cream was heated the more efficient
was the process. While it is impractical to heat milk, for domestic
use, above 145° F., cream for butter-making can be heated to a
much higher temperature. Milk or cream with a “strong”
onion flavor was used. As to results, the onion flavor was
removed from milk held at a temperature of 145° F. in from
thirty to sixty minutes; while the flavor was wholly removed from
cream, held at a temperature of 160° F. in forty minutes.

A considerable amount of investigational work has been done
by the Extension Department of the Purdue Station, Indiana, on
the eradication of wild garlic. We quote from what they have
to say, as follows:

“To Eradicate Wild Garlic on a Large Scale.—Break the
infested land late in the fall, plowing to such a depth as to turn —
up as many of the garlic bulbs as possible. Leave in this con-
dition through the winter. Replow the field very early in the
spring—not later than the tenth of April, if possible—disk and
harrow at least a couple of times and plant to some summer crop
such as corn, soy beans, cow-peas, potatoes, sorghum or millet.
No garlic plants or very few will appear during the summer,
but they will start their growth again in the fall. Remove the
crop in time to allow another breaking late in the fall. Repeat
as outlined for the first year, that is, break the field in the fall
and again early in the spring and plant to summer crop. This
process continued every season for three to five years will clean
out the garlic entirely.

‘“To Eradicate Wild Garlic on a Small Scale.—Spray the
plants about the middle of April with orchard heating oil. The
oil destroys the plants entirely. More garlic may come up,
however, the following fall or spring from the bulbs which had
not germinated in the previous season. These must be sprayed
again. The treatment may have to be repeated, in some cases,
even in the third year.”

The surest remedy for overcoming these defects in milk and
cream is to keep the cows in pastures where the said obnoxious
plants do not grow. Nitrate of potash, common saltpeter, has
been used quite extensively in cheese sections of the country in

SOME OF THE CAUSES AND THEIR PREVENTION 329

the late fall months, when turnip tops or turnips were fed, for
the purpose of eliminating or removing odors from milk pro-
duced by cows having access to turnip tops or turnips.

For butter-making, the German government permits the
addition of nitrate of potash to milk or cream for the purpose of
removing flavors produced by the cows eating beets or beet tops.
Onions and garlic predominate in the early spring and soon dis-
appear. As soon as the grass advances to such an extent that it
supplies the wants of the cows, they prefer it to weeds of any kind.

Advance in Lactation, Winter Feeds and Stable Conditions.—
It is thought by many that the advanced period of lactation has a
pronounced detrimental effect on the flavor of butter. Experi-
ments conducted at the Iowa Experiment Station in 1896 (Bul-
letin 33. pages 606-609), by McKay and Eckles, do not sub-
stantiate this theory. In the various tests made the milk
from the Experiment Station herd was used. The milk of
fifteen cows, which averaged an advance of 239 days in their
lactation period, was classed as stripper milk; while the milk
of seventeen cows, which averaged an advance of 107 days in
their lactation period, was classed as milk from fresh cows.
During this experiment the cows were on good blue grass
and were being fed, in addition, one-quarter of a pound of
cottonseed meal at the beginning of the period. The cotton-
seed meal was gradually increased, until at the end of the experi-
ment they received 1 pound each per day. The milking was
done under personal supervision so that no error might be made
- through mixing the milk from the two lots. After being milked
and strained into cans the milk was taken directly to the cream-
ery. When the evening’s milk was taken to the creamery it was
aerated and put in an ice-box which was filled nearly to the top
of the cans with ice and water. This kept the milk in good con-
dition until the next morning, when the evening’s milk and the
morning’s milk were mixed together and separated.

The milk from the fresh cows was separated and cared for in
the same manner as that from the strippers. In order to make a
closer connection between flavors a starter was prepared from the
mixed milk of two stripper cows, the periods of lactation of which

330 DEFECTS FOUND IN BUTTER

were 339 and 356 days. The skim-milk from the stripper milk
was permitted to sour and was then used as a starter for souring
or ripening the cream separated from the stripper milk. The
fresh cow’s milk used for a starter was produced by a cow that
had been thirty days in lactation. The skim-milk was per-
mitted to sour in the same way as that from the milk of stripper
COWS.

Various tests were made of the butter made from the dif-
ferent milks. This butter was scored by W. S. Moore, who was
then official scorer for the Elgin Board of Trade, and knew
nothing of the nature of the experiment. ‘The tubs of butter
were all scored by number, and received practically the same
score. The two highest-scoring lots of butter scored 95; one
of these lots was made from the stripper milk and the other
from fresh cows’ milk.

From this and similar experiments reported in Bulletin No. 32,
Iowa Experiment Station, it would seem that the period of lac-
tation has little or no effect upon the flavor of butter, that is,
when the milk is separated by centrifugal force, or by the little
hand separator. Under the gravity system there may be some
difference, as many dairymen claim there is. A possible explana-
tion is that the fat-globules, as is well known, are smaller in the
milk of cows well advanced in lactation, and when cream from
such milk is raised by the gravity process more time is required
for the cream to ris¢é than when the milk is from fresh cows
whose milk contains fat-globules of much greater size.

A bitter flavor is frequently found in milk or cream that is
kept for a long time at a low temperature.. There seems to be
present in almost all milk an organism that is able to produce a
bitter flavor in milk or cream at low temperatures, which are
unfavorable to the development of the lactic acid organisms.
Hence, the defects attributed to the period of lactation of the cow
may be due to the method of separating the cream.

It is the aim of almost all farmers to have their cows come in
fresh in the spring. Therefore, during the early winter months
most of the cows are well advanced in their period of lactation.
At this time they are milked in the stables and fed on dry feed,

SOME OF THE CAUSES AND THEIR PREVENTION 331

hence, the opportunity for the milk to become inoculated with
undesirable organisms is very great. Such conditions are apt
to create in the minds of some the wrong impression that the
defects found under winter conditions are caused by the advanced
stage of lactation.

Most butter manufactured in the winter has what butter
judges and dealers term winter flavors. Where the milk is
received sweet at the creameries and the cream is separated and
pasteurized and a good starter is used, winter conditions can be
overcome. ‘The importance of pasteurization and the use of a
good starter during the winter months cannot be emphasized
too strongly.

A quotation from Bulletin ror, Iowa Experiment Station,
page 167, will help to show the improvement that can be made
in the flavor of butter under right methods. ‘ During the spe-
cial winter course, beginning the latter part of December, 1907,
and continuing until January, 1908, the Dairy Department of
the lowa Experiment Station arranged with the Randall Cream-
ery Company, Randall, Iowa, to purchase their cream to be used
during the special short-course.” In this case it is presumed that
the cows were well advanced in the period of lactation, they were
certainly subject to normal winter conditions. The Randall
Creamery, which is a whole-milk creamery, received the milk
and separated it. The sweet cream, in this case, was shipped to
the Iowa Experiment Station where it was pasteurized, ripened
by the use of a good starter and churned the next morning. The
cream skimmed at the plant contained 42 to 45 per cent butter-fat,
after the starter was added it contained 32 to an per cent tat:
As the Randall Creamery Company were shipping their butter
to Gude Bros., New York, they made a request that the butter
produced from their cream at the Iowa Experiment Station be
shipped to the same place. This was done, with instructions
to the Gude Bros. and P. H. Keiffer, the well-known butter judge
of that firm, to score each shipment critically and report on the
same. At the close of the shipments, Mr. Keiffer made the
following report:

“Tam very much pleased to be able to report that the butter

332 DEFECTS FOUND IN BUTTER

which you shipped us this winter, made from cream obtained
from the Randall Creamery during the ‘ Short Course,’ was very
fancy, and scored from 93 to 96 points. Very little butter
arrived at that time as fine in flavor as this. Our best trade was
well pleased with your butter. I wish that more of the cream-
eries were making this high quality butter at the time of year
when it is so difficult to make it. The workmanship was perfect
in every respect, so far as I could see, and the flavor was fine.”

If the above-mentioned cream had been permitted to sour
naturally the chances are that the flavor would have been very
inferior instead of fine. The authors have found the best tem-
perature for ripening cream during the winter months to be 70°
© qu 18.

From the above it seems that the flavor of the butter is not
injured by the advance in the lactation period of the cow but
rather by undesirable fermentations that develop in the cream if
permitted to sour naturally, especially during the winter months.

Tallowy Flavor.—Tallowy flavor is sometimes found in butter,
usually in butter that has been kept under rather unfavorable
conditions. Butter of this character has a taste somewhat
similar to that of old tallow. This peculiar flavor is more apt to
develop in print than in tub butter. It occurs, however, in tub
butter when it has been bored a number of times, thus bringing
the air into contact with the inner parts of it. It is found some-
times in print butter which has been exposed to the air and
light, and the color may be seriously affected, even to the extent
of bleaching the surface butter white.

The cause of tallowy flavor in butter is oxidation. U. S.
Bulletin 84 shows the effect of air on the quality of butter. A
number of cans of butter were put up by Gray, and hermetically
sealed. Some of these cans were packed full, some about three-
quarters full, some about half full, and the butter in one lot was
put in loosely where the air came into contact with it. Thus,
the amount of butter in these cans was so varied that different-
sized air spaces were left. The solidly packed butter in every
instance kept the best in storage. ‘The butter that was loosely
packed deteriorated very rapidly, showing a tallowy or fishy

SOME OF THE CAUSES AND THEIR PREVENTION 333

flavor. Mr. Gray, in commenting upon this butter, makes the
following statement:

““Comparing the average scores of butter in full cans and in
partially full cans it will be noted that there were differences of
r to 5 points in favor of the fullcans. It does not seem necessary
to take up these differences in detail. This deterioration was
without doubt due to air in the partially full cans. Since in
packing butter in cans there is no necessity for having the cans
only partially full, neither is this economical, the writer does not
hesitate to state that where the sealing is done at atmospheric
pressure the cans should be entirely filled, leaving as little air
space as possible. This principle may be applied to packing
butter in other packages. The butter should be packed solidly,
leaving as few air spaces as possible. Air having a deteriorating
effect on the keeping of storage butter, it would be expected that
butter stored in small open packages, as pound prints, would
not keep so well as butter in large packages. This is a belief
that has already been accepted by many.”

High-scoring butter that has been bored a number of times at
conventions or butter contests, has a tendency to deteriorate in
quality and show a slight tallowy flavor. One of the authors
has had the opportunity of judging butter at various times in
almost every dairy state in this country, and in some of the foreign
countries, thus being afforded a wide range of opportunity for
examining prize-winning tubs or packages of butter.

The impression prevails with some that high-scoring butter
lacks keeping quality. The only way whereby this statement
could be verified would be to place a tub of the same butter in
storage and leave it there at storage temperature for six or seven
months. When we take into consideration that some of the
best butter at a contest is bored a great many times and thus
exposed to the air, it would be difficult to determine whether the
defect in the butter were caused by high ripening or by excessive
boring. An instance of excessive boring was brought to the
attention of the authors in a national contest that was held at
Milwaukee some years ago, where both authors were present
acting in the capacity of experts, one pointing out the defects in

304 DEFECTS FOUND IN BUTTER

the butter and the other writing each exhibitor giving suggestions
as to the possible cause of the defects existing.. Three well-
known judges worked in this contest, one from Philadelphia,
one from Boston and the third from Chicago. There were
between seven and eight hundred entries of butter exhibited.
On the first day’s scoring the judges set aside a tub of extra
fine butter to be rescored. The butter had a fine aroma and a
clean palate flavor. It had what the authors would describe as a
creamy, pleasant flavor. The quality of this butter was such
that it was used as a standard by which to gage the score of the
other tubs of butter in the final scoring. It is the custom in a
large contest of this kind for the judges to set aside all butter
that will score as high as 95 points out of a possible roo. This
butter is placed in what the judges term the “ shake-down.”
After all the other butter is scored, the judges after resting for
some time go to work on the “ shake-down” with a view to
placing the highest scores. This particular tub of butter was
used as a standard by which to fix the other grades. The result
was that this butter was bored possibly twenty-five or thirty
times. When the judges in the final score placed this tub fourth,
on the ground that it was showing at that time a slight tallowy
flavor, their decision caused some dissension and dissatisfaction.
It certainly was not fair to this exhibitor to have his butter bored
so many times, and the authors believe that the repeated boring
of a tub of butter in a contest with the resulting contact with the
air is not a fair test of its keeping qualities.

The bleaching of tallowy butter does not usually occur until
it has been held for some time. Tallowy flavor is not very
frequently found in butter that has been placed in cold storage.

Overworking butter to the extent that it will become greasy
in appearance and taste has a tendency to cause tallowy flavor.
By overworking butter, extra air is incorporated. Butter that is
churned in such condition that the granules will gather firm
will stand an extra amount of working without any effect upon
the body. If cream is churned immediately after reaching churn-
ing temperature, before the fat has sufficient time to be thor-
oughly chilled, the fat has a tendency to gather in a soft condi-

)

SOME OF THE CAUSES AND THEIR PREVENTION 3909

tion, and if such butter is worked to the extent of avoiding mot-
tles and thoroughly incorporating the salt, there is danger
of the body being seriously affected and the butter having a
greasy or lardy taste.

Butter which has been well made and kept away from the light
when placed in storage will seldom, if ever, show a tallowy flavor.

Metallic Flavors.—A heavy loss is sustained by the butter
industry every year through metallic and fishy flavors. There
does not seem to be a clear understanding between some butter
judges as to the distinction between these two classes of flavors.
Metallic flavor and fishy flavor are two entirely different things.

Metallic flavor shows in the butter as soon as it is churned
and is invariably found in butter made from extremely sour
cream, while fishy flavor develops in butter on standing. What
actually causes metallic flavor is not thoroughly understood, and
various causes have been assigned by different people. Metallic
butter has a pungent flavor, characteristic of the taste of metallic
salts. Many people are of the opinion that cream acquires a
metallic flavor by being shipped in rusty cans or coming in
contact with vats or coils from which a portion of the tin has
been removed.

Certain creameries have reported that in some cases the first
churning from a vat of cream is free from metallic flavor, while
this flavor is present in the second churning from the same vat.
This would seem to indicate that the flavor is due to the develop-

ment of some undesirable fermentation, or to bacterial action.

The peculiar feature about metallic flavor is that it is a sea-
sonal condition; it comes and disappears. Heat seems to inten-
sify it or make it more pronounced. The authors have known
creameries that were troubled with metallic flavor which dis-
appeared when they discontinued pasteurization. Cream coming
in contact with vats, coils or cans from which the tin has been
removed may develop a metallic flavor as a result of this. How-
ever, when we take into consideration that metallic flavor is a
seasonal condition, the theory of rusty cans or the partial
removal of tin from vats or coils does not offer a complete explan-
ation, as creamerymen use the same cans and vats during the

336 DEFECTS FOUND IN BUTTER

entire season. If the trouble were wholly due to the removal of
the tin from the vats or coils, it would continue throughout the
year.

Guthrie reports that he placed 157 samples of cream in sterile
glass bottles and inoculated with an individual species of bacteria,
and that 52 showed metallic flavor. Naturally the creamery-
men will be more interested in what will prevent metallic flavor
than what causes it.

One of the largest creamery companies in this country
which, like others, was formerly troubled with metallic flavor
claims it has not had any difficulty for several years, due to the
method observed in manufacturing. The president of the com-
pany stated to one of the authors that they had bid good-bye
to metallic flavor several years ago. ‘The method they pursue
is neutralization to a low degree of acidity and thorough cleanli-
ness. If metallic flavor makes its appearance they reduce the
acidity to .27 per cent before pasteurization and then again, by
adding limewater, reduce the acidity to .o4 or .o5 per cent, and
ripen with a pure culture. In addition to this, they thoroughly
cleanse all pipes and faucets, and everything else with which the
cream comes in contact. They maintain that this method of
procedure has entirely eliminated metallic flavor from the
butter they manufacture.

Fishy Flavor.—Fishy flavor causes greater losses in butter
than any other one defect. In recent years a great many so-
called discoveries have been made by different scientists as to the
actual cause of fishy flavor. ‘These discoveries have been inves-
tigated and disputed by other scientists, and the result is that
fishy flavor is still with us. Butter made from high-acid cream
will invariably go fishy if placed in cold storage for a long time, or
for the natural storage period.

Prior to the introduction of partial neutralization of acidity
in cream, butter made from hand-separator cream containing a
high per cent of acid invariably turned fishy when kept in storage |
for any length of time. One of the leading dealers in Chicago
stated that for two years he had bought butter made by some of
the large creameries from sour cream the acidity of which had

SOME OF THE CAUSES AND THEIR PREVENTION 337

not been reduced, and that in almost every case the butter was
fishy when it came out of storage. He said that as a result of
this he had made up his mind never to buy any butter from the
so-called centralized creameries. The same firm now prefers to
buy butter for storage purposes from large creameries where the
acidity of the cream is reduced or controlled.

The following is a quotation from U. S. Bulletin by L. A.
Rogers, S. C. Thompson and J. R. Keithley, page 8:

“In a tabulation of the examination of 259 samples of
experimental butter from cream of known acidity, of 137 sam-
ples from cream having an acidity below 0.3 per cent, only 2, or
I.5 per cent, were marked ‘ fishy,’ while of 122 samples having
an acidity of 0.3 per cent or over, 60, or 49.2 per cent, were fishy.
However, in all results which are dependent on the sense of
taste, allowance should be made for difference of opinion and in
the conception of the flavor associated with any particular
designation.”

U.S. Department of Agriculture Bulletin 84, page 23, 1906,
by C. E. Gray and G. L. McKay, entitled “‘ The Keeping Qual-
ities of Butter made under Different Conditions and Stored at
Different Temperatures,” would indicate that acid has a pro-
nounced effect in producing fishy flavor in butter unless the
acidity of the cream has been reduced by partial neutralization.
In this investigation part of the butter was made at Topeka,
Kansas, from sour cream. Other lots were made at Monticello,
- Iowa, from sweet or whole-milk cream. The butter made from
sweet cream did not turn fishy in storage, while practically all
the butter made from sour cream had a pronounced fishy flavor
after being kept in storage for some time.

Fishy flavor may be prevented with certainty by making
butter from pasteurized sweet,cream. Butter made from pas-
teurized sweet cream with a starter added, but without ripening,
seldom if ever becomes fishy.

Of 25 different churnings of cream made at Strawberry Point,
Iowa, July, 1907 (Bulletin 101, by McKay and Bower, page 164),
8 were made from unpasteurized cream and 17 from pasteurized
cream. The cream was ripened in all cases with a pure culture

338 DEFECTS FOUND IN BUTTER

starter, average acidity developed .68 per cent. A tub of butter
from each churning was stored in New York between six and
seven months, and came out of storage without any trace of a
fishy flavor. The butter was scored when entering storage and
when coming out by P. H. Keiffer, the well-known butter judge.
The average scores on flavor were, first scoring 38.17, second
scoring 38.25. The butter was pronounced by the expert
scorer as being some of the finest butter he had ever seen come
out of storage. Two 56-pound boxes from each churning were
shipped to London, Liverpool, and Manchester, England, where
they were scored by experts and pronounced unusually fine.
The average in England, on flavor, was 38.5. The Strawberry
Point Creamery at that time received about 50,000 pounds of
milk daily. The milk was all inspected before being taken into
the creamery, and any milk that was sour or tainted was rejected.
The milk was all separated by power separators and the cream
skimmed so as to contain a high per cent of milk-fat. The high
per cent of acid developed in this case apparently had no effect
upon the keeping quality and did not produce a fishy flavor.
It would, therefore, seem that the quality of the milk or cream
used in the manufacture of butter is somewhat responsible for
its going fishy.

The Danish butter, which has gained a world-wide reputa-
tion, is practically all made from whole milk delivered at the
factories, the cream being ripened with a culture starter. While
cream of high acid has a tendency to go fishy, fishiness cannot
be attributed entirely to the development of acid in cream. At
the present time probably go per cent of the butter produced in
this country is produced from cream separated on the farms.
The washing of the separators and other dairy utensils is entirely
in the hands of the producer. It is only reasonable to suppose
that some of the patrons of almost every creamery do not pursue
sanitary methods in the care of their separators and other utensils
that come in contact with the cream. Such cream is undoubt-
edly inoculated with undesirable organisms before it reaches the
creamery, and if an attempt is made to ripen or develop much
acid in it, other changes will also take place. To make butter

SOME OF THE CAUSES AND THEIR PREVENTION 339

possessing good keeping qualities, under present conditions, it is
necessary to neutralize when the cream is very sour, and develop
a low degree of acidity. The Dairy Division has found that
pasteurizing cream with a low degree of acidity and churning it
sweet, or without the use of a starter, produces a butter that is
entirely free from fishy flavor.

CHAPTER XXII
JUDGING AND GRADING BUTTER

BUTTER may be judged from a commercial and from an indi-
vidual standpoint. Individual judgments of the same butter
may vary considerably. It is important that the judge should
become familiar with the quality of butter as required by our
standard markets, and then judge the butter according to the
demands of the mass of the consumers, rather than according
to personal likes and dislikes. In order to become a good butter-
judge, it is essential that the senses of taste and smell be acute.
Even if one’s taste and smell are keen and sensitive, consider-
able practice or experience is necessary. Almost any one can
tell a good sample of butter from a very poor one, but when it
comes to differentiating between two samples which are nearly
alike in quality, skill and experience are required.

The chief requirement in scoring butter is to become thor-
oughly familiar with the ideal flavor of butter; then by repeated
comparisons of different samples of butter with this ideal
flavor, one will soon become efficient in grading the butter.

Standard for Judging.—In America the distinct qualities
which are noticed in butter are designated according to the
basis of points given below. It will be noticed that different
values are given to the different characteristics, according to their
relative importance. ‘The score-card given below is used com-
mercially, and is based upon too as the perfect score:

SCORE CARD

IN@s s 206 Perfect Score Remarks

HIE INGCO) RA eres as ae ucss eS) GI Sr ce eee AB VOD cal ae ee aa Res bins ee ae
ABXOYG bicee aetna Sia eicedects Sic ove are’ Oh Awesiha LS ee ee a er
Colon a ale eres aaa ale TS) Agia eek) Sew Sok las Rn
Salles reac canoes sae nae An eR TOs rapa lectetin piven S nlinks euler
Styles Meee cae same te toe 5 eee we eee ees. AMBER ee

TRO tall sie eee ee ce eae 100
Dates vsti kt aoe ume e erase Scored’ by. suse0.2 is ieee

340

MANNER OF JUDGING 341

MANNER OF JUDGING

Body.—After the trierful of butter has been drawn out, the
first thing to notice is the aroma, and the body or texture of the
butter. The butter on the outside should be examined at once
before it is affected by the temperature of the room. Notice its
color, whether it is even or uneven, low or high. Determine by
the appearance of the butter and the way it feels to the palate
whether it is greasy, tallowy, spongy, or sticky. The amount
and condition of brine should also be noted. These character-
istics and their causes have been previously discussed.. Stroke
the plug of butter with a knife to observe the color closer. Squeeze
it with the thumb to ascertain the character of the body. The
aroma of the butter should also be noticed in connection with
scoring the butter on body or texture, as it is more pro-
nounced immediately after the trierful of butter has been
drawn.

Flavor.—It is impossible to describe all the different flavors
found in butter. There are perhaps as many distinct butter
flavors as there are shades of color. However, there are a few
flavors which stand out more prominently and are more commonly
met with than any of the others. Good butter should possess a
clean, mild, rich, creamy flavor, and should have a delicate, mild,
pleasant aroma. Some butter-judges, especially foreign judges,
allow a separate number of points for aroma of butter in the score-
card. This has been suggested in the United States also, owing
to the fact that butter may have little aroma and still have a good
flavor.

Color.—The color should be bright and even. When a plug
of butter is drawn with a trier and is held up to the light, it
should not be cloudy and dense, but should be almost trans-
parent and bright. The chief fault found with the color of
butter is unevenness. It may be streaky or mottled, or it may
be too high or too low. The shade of color will vary according-to—
the different markets; in most of our markets a straw color is
preferred. There has been a tendency recently to recommend a
comparatively light shade of color in butter. A reddish color

342 JUDGING AND GRADING OF BUTTER

should be guarded against, except when the market demands
it. If too much color is added, butter will assume this hue,
which is undesirable.

Salt.—The amount of salt likewise depends upon the market,
and unless the salt-content is extremely high, or extremely low,
butter should not be criticized on account of the amount of salt.
The chief thing to consider in judging butter on its salt-content
is the condition of the salt. Notice whether it has been thor-
oughly dissolved and evenly distributed.

Style.—The style is the appearance of the butter and package.
Whatever the shape of the package, the chief thing to consider
is whether it is clean and neatly finished.

CLASSIFICATION—GRADES AND SCORES

While the different butter markets differ more or less as to
details, in their classification and grading of butter, they corre-
spond closely when it comes to the large essentials. As the New
York and Chicago markets are the two great butter markets of
the United States, the following is quoted from the Rules of the
New York and Chicago Mercantile Exchanges, respectively:

New York

1. Butter shall be classified as Creamery, Renovated, Ladles,
Packing Stock and Grease Butter.

DEFINITIONS

2. Creamery.—Butter offered under this classification shall
have been made in a creamery from cream separated at the
creamery or gathered from farmers.

3. Renovated.—Butter offered under this classification shall
be such as is made by melting butter, clarifying the fat therefrom
and rechurning the same with fresh milk, cream or skim-milk, or
other similar process.

4. Ladles.—Butter offered under this classification shall be
such as is collected in rolls, lumps, or in whole packages and
reworked by the dealer or shipper.

CLASSIFICATION—GRADES AND SCORES 343

5. Packing Stock.—Butter offered under this classification
shall be original farm-made butter in rolls, lumps or otherwise,
without additional moisture or salt.

6. Grease butter shall comprise all classes of butter grading
below thirds, or of packing stock grading below No. 3 as herein-
after specified free from adulteration.

GRADES

7. Creamery, renovated and ladles shall be graded as extras,
firsts, seconds and thirds; and packing stock shall be graded as
No. 1, No. 2 and No. 3.

DEFINITION OF GRADES

_ 8. Grades of salted butter must conform to the following
requirements:

Extras

g. Shall be a standard grade of average fancy quality in the
season when offered under the various classifications. Ninety
per cent shall conform to the following standard; the balance
shall not grade below firsts:

Flavor —Must be sweet, fresh and clean for the season when
offered if creamery, or sweet, fresh and reasonably clean if ren-
ovated or ladles.

Body.—Must be firm and uniform.

Color.—Not higher than natural grass, nor lighter than light
straw, but should not be streaked or mottled.

Salt.— Medium salted.

Package.—Sound, good, uniform and clean.

Firsts

10. Shall be a grade next below extras and must be good butter
for the season when made and offered, under the various classi-
fications. Ninety per cent shall conform to the following stand-
ard; the balance shall not grade below seconds.

Flavor-—Must be reasonably sweet, reasonably clean and
fresh if creamery or renovated, and reasonably sweet if ladles.

Body.—Must be firm and fairly uniform.

344. JUDGING AND GRADING OF BUTTER

Color.—Reasonably uniform, neither very high nor very light.
Salt.—May be reasonably high, light or medium.
Package.—Sound, good, uniform and clean.

Seconds

11. Shall be a grade next below Firsts.

Flavor.—Must be reasonably good.

Body.—li Creamery, must be solid boring. If Ladles or
Renovated, must be 90 per cent solid boring.

Color.—Fairly uniform, but may be mottled.

Salt.—May be high, medium or light.

Package.—Good and uniform.

Thirds

12. Shall be a grade below Seconds and may consist of pro-
miscuous lots.

Flavor —May be off-flavored and strong on tops and sides.

Body.—Not required to draw a full trier.

Color.—May be irregular or mottled.

Salt.—High, light or irregular.

Package.—Any kind of package mentioned at time of sale.

13. (For grades higher than Extras, see paragraph No. 28).

No. 1 Packing Stock

14. Shall be sweet and sound, packed in large, new or good
uniform second-hand barrels, having a wooden head in each end,
or in new tubs, either to be parchment paper lined. Barrels and
tubs to be packed full.

No. 2 Packing Stock

15. Shall be reasonably sweet and sound, and may be packed
in promiscuous or different kinds of barrels, tubs or tierces, with-
out being parchment paper lined, and may be packed in either
two-headed or cloth-covered barrels.

No. 3 Packing Stock

16. Shall be a grade below No. 2, and may be off-flavored, or
strong; may be packed in any kind or kinds of packages.

CLASSIFICATION—GRADES AND SCORES 345

17. Charges for inspection of Packing Stock shall be the same
as the rules call for on other grades.
18. Mold.—There shall be no grade for butter that shows
mold.
Scoring
19. Scoring.—The standard official score shall be as follows
and shall apply to Salted Creamery Butter only:

Points
TSTA NO Terie ately ete opin tera aera Ei awe Ree Man) 45
I BXOVGINY/ 5 yo: deg Bob at Se aT Rann OR aT rR 25
(CrONG TES areata gat Lek ester a ce en us
Salltegee eis, aa ema Oe i Rhven!y.o%) etic Wat | 1K)
Sy Crap yh eerie tits sachet oe teh nent kN) hay as 5
100

20. Extra Creamery may score either 91, 92 or 93 points at
the discretion of the Butter Committee, who shall determine the
required score from time to time in such manner that it shall
represent an average fancy quality in the season when offered.
But butter scoring more than required for Extras shall be deliv-
erable on a contract for Extras, and may be branded as such at the
request of seller, or buyer. Any change in the Standard score
required for Extras shall, after authorization by the Butter Com-
mittee, be announced by the caller at the opening of the next
regular call and posted upon the bulletin board of the Exchange
and be effective twenty-four hours later.

21. The minimum score of Firsts shall, at all times, be 4
points below the score required for Extras.

22. The minimum score of Seconds shall be 5 points below
the minimum score required for Firsts.

23. The minimum score of Thirds shall be 7 points below the
minimum score required for Seconds.

UNSALTED CREAMERY
Extras

24. Shall be a standard grade of average fancy quality in the
season when offered under the various classifications. Ninety

346 JUDGING AND GRADING OF BUTTER

per cent shall conform to the following standard; the balance
shall not grade below Firsts.

Flavor —Must be sweet, fresh and clean for the season when
offered.

Body.—Must be firm and uniform.

Color.—May be very light straw, white, or natural grass, but
must not be streaked or mottled. The seller must specify the
color at time of sale.

Package.—New, uniform and clean.

Firsts

25. Shall be a grade next below Extras and must be good
butter for the season when made and offered, under the various
classifications. Ninety per cent shall conform to the following
standard; the balance shall not grade below Seconas.

Flavor.—Must be reasonably sweet, reasonably clean and
fresh.

Body.—Must be firm and fairly uniform.

Color.—May be very light straw, white, or natural grass, but
must not be streaked or mottled. The seller must specify the
color at time of sale.

Package.—Sound, good, uniform and clean.

Seconds

26. Shall be a grade next below Firsts.
Flavor.—Must be reasonably good.
Body.—Must be solid boring.

Color.—Fairly uniform, but may be mottled.
Package.—Good and uniform.

Thirds

27. Shall be a grade below Seconds and may consist of
promiscuous lots.

Flavor.—May be off-flavored and strong on tops and sides.

Body.—Not required to draw a full trier.

Color.—May be irregular or mottled.

Package.—Any kind of package mentioned at time of sale.

CLASSIFICATION—GRADES AND SCORES 347

Scoring
Points
IBIBO s 3 < SERTO e, Fe e Sa 45
LBOGIY aki cliches A eee ot een cts CTs aR 25
(COlOIR, 620 AOI Geet nce ae PRE Naima 20
SSSA CRIME rast Greeley he aR EC A ade cuter Sa IO
I0O

SALES UNDER THE CALL

28. Creamery butter salted of a score higher than required
for Extras may be offered and bid for by score. The score of
such butter may be considered its grade; or such higher scoring
butter may be delivered on a contract for Extras. This grade
of butter, above ‘‘ Extras,” is commonly designated by the trade
as ‘‘ Specials.”

Chicago

1. Butter shall be classified as Creamery, Centralized Cream-
ery, Held Butter, Renovated, Ladles, Packing Stock and Grease
Butter.

DEFINITIONS

2. Creamery.—Butter offered under this classification must
be made in a creamery, the cream having either been separated
from the whole milk at the creamery or received by team or
motor at the creamery direct from the farm.

3. Centralized Creamery.—Butter offered under this classi-
fication must be made in a creamery. The cream used in the
manufacture of this butter may be gathered direct from the
farmer or shipped in from individual shippers or cream stations.

4. Held Butter.—Butter offered under this classification
shall be butter that has become cold storage butter by virtue
of the laws of the United States or of the state in which such
butter is sold.

5. Renovated.—Butter offered under this classification shall
be such as is made by melting the butter, clarifying the fat
therefrom and rechurning the same with fresh milk, cream, skim-
milk or other similar processes.

348 JUDGING AND GRADING OF BUTTER

6. Ladles.—Butter offered under this classification shall be
such as is collected in rolls, lumps or whole packages and reworked
or rechurned, resalted or recolored by the dealer or shipper.

7. Packing Stock.—Butter offered under this classification
shall be original butter without additional moisture or salt from
creamery or dairy (but may be from miscellaneous sources),
which has been collected in any quantity and packed in tubs,
barrels or other containers. It must be of a quality fit for
human consumption as food and free from adulteration.

8. Grease Butter.—Butter offered under this classification
shall consist of all grades of butter below thirds. If packing stock,
below No. 3, and free from adulteration.

GRADES

9. Creamery and Held Creamery shall be graded Extras,
Firsts, Seconds and Thirds. Centralized Creamery shall be
graded Extras, Standards, Firsts, Seconds and Thirds. Reno-
vated and Ladles as Firsts and Seconds. Packing Stock as
No. 1, No. 2, and No. 3.

Scoring

10. The standard official score for salted butter shall be as

follows:

Points |
LES oy aenass Clem Meine eins deine name Up aE a sn de 2 45
1 BLOC hygiene a ene lean eM 8 25
ClO Ran: Le ye ies at one clan cao A ae een 15
Gals nee ter Racers <0 Cant ae ee ae eee IO
Siiyle tek teks os oh eA a ee a 5

11. The standard official score for unsalted creamery butter
shall be as follows:

Points
AVR cccpet vai dke co ci.) cet, eguaclles Meet mee 45
I BGG bien ye eae year ci erML Emer ase sca ced oid 30
Golotesieut pote Sei aie lA eee eae 15
Style nee aeberhuSt. (ke cb cacherd ta he oe ee eee ie)

12. All grades of butter must conform to the following require-
ments:

CLASSIFICATION—GRADES AND SCORES 349

Extras

13. Shall consist of the best grade of butter in the season when
produced and must score 92 points or better.

Flavor must be sweet, fresh and clean when offered as fresh,
and sweet and clean when offered as Held Creamery. Body
must be firm and of good texture. Color may be either light
straw color, medium or high, but must be uniform and neither
streaked nor mottled. Salt may be defined as light, medium or
high, but must not be gritty. Package, new, sound, good, uni-
form and clean.

Standards

r4. Standards shall be a grade of centralized creamery of’
average fine quality in the season when offered, scoring 90 points
and above. Flavor must be fresh and clean if fresh, and clean
if held. Body must be firm and of good texture. Color may be
either light straw color, medium or high, but must be uniform,
neither streaked nor mottled. Salt may be defined as light
medium or high, but must not be gritty. Package, new, sound,
good, uniform and clean.

Firsts

15. Shall be a grade just below Extras, scoring from 88 to
(but not including) 92 points, must be good butter for the season
when made and offered under this classification.

Flavor must be reasonably clean and fresh if Creamery,
Centralized Creamery or Renovated, and reasonably clean and
reasonably sweet if Held. Body must be firm and of fairly good
texture. Color reasonably uniform, neither very high nor very
light. Salt may be light medium or high. Package, new, sound,
good, uniform and clean. If Ladles, must be 90 per cent solid
boring, color reasonably uniform, package sound and clean.

Seconds :

16. Shall be a grade below Firsts. The minimum scoring of
Creamery Seconds shall be 4 points below the minimum scoring
required for Firsts or a range of from 84 to (but not including) 88.

Flavor must be fairly good. Body, if Creamery, Centralized

350 JUDGING AND GRADING OF BUTTER

Creamery or Held, must be solid boring. If Renovated or Ladles,
must be 90 per cent solid boring. Color, fairly uniform, but
may be mottled. Salt may be light medium or high. Package,
good and uniform.

Thirds

17. Shall be a grade below Seconds and may consist of pro-
miscuous lots. The minimum scoring for Creamery Thirds shal!
be 5 points below the minimum scoring for Seconds, or a range
from 79 to (but not including) 84 points.

Flavor may be off-flavored and strong on tops and sides, more
or less rancid. Body not required to draw a full trier. Color
may be irregular or mottled. Salt high, light or irregular.
Package, any kind of package mentioned at delivery.

No. 1 Packing Stock

18. Shall be original butter, solid boring, sweet and sound,
without additional moisture or salt, free from mold, normal in oil
contents, packed in barrels or in tubs or boxes. Where in bar-
rels, parchment-lined packages are preferred. When in either
tubs, boxes or barrels, same should be packed full.

No. 2 Packing Stock

19. Shall be original butter, 85 per cent of it solid boring, the
other 15 per cent fairly solid boring, reasonably sweet and sound
for the grade offered; may be slightly deficient in oil contents,
must be free from mold and may be packed in different kinds of
barrels, tierces, pails or boxes with or without paper lining.

No. 3 Packing Stock

20. Shall be a grade of quality just below No. 2 Packing
Stock, but above the classification of Grease Butter; may be
packed in any or all kinds of packages.

EXPORT BUTTER

The observations of the authors have been that the reputation
of the American butter on the English market is not all that is
desirable. Some American butter is good enough to sell on an

EXPORT BUTTER ool

equality with Danish butter, and in some instances it is palmed
off as such. Much poor butter, however, has been allowed to
go to the English market, and this has in some measure ruined
the reputation of our butter.

Butter for export purposes should be of the very best, and
made in such a way as to insure good keeping qualities.

Fic. 128.—Shipping Russian Butter from Siberia. (U.S. Govt. Bul.)

The standing of the different kinds of butter, as observed
on the English market, were as follows:

(1) Fresh French Rolls.

(2) Danish Creamery.

(3) Irish Creamery.

(4) New Zealand.

(5) Canadian, Australian, Argentine, United States, and
Siberia.

For Storage Purposes

(1) Danish.

(2) New Zealand.

(3) Siberia.

CHAPTER XXIII
COLD STORAGE AND BUTTER FOR STORAGE PURPOSES

History of Cold Storage.—From early pioneer days the people
had a knowledge of the fact that by placing perishable food
products where the temperature was low they could keep them
much better. Many of the early settlers discovered that there
was a zone about 6 to 1o feet below the surface of the ground
where the temperature was low. Hence they dug holes in the
ground in which to keep various kinds of food products. Later,
ice was used in various ways to lower the temperature. It was
discovered that the lower the temperature, the better the food
products would hold their flavor.

Refrigeration, as we have it to-day, is the result of a gradual
evolution as to both process and efficiency. Cooling by means,
of ice was practiced by the ancients. We read that the monarch,
Nero, had ice-houses built in Rome for the storing of natural ice.
The cooling effect obtained through dissolving certain salts was
recognized and made use of, as far back as 1762, by. Fahrenheit,
the inventor of the thermometer that bears his name. Salt-
and-ice mixtures have been used for many years for refrigerating
purposes, including the making of ice-cream, etc. In what is
known as the ‘‘ Cooper System ”’ of refrigeration, ice and calcium
chloride are used. Under this system the temperature of a well-
constructed refrigerator can be maintained at 20° F., or below.

About 1845, Dr. Gorrie of New Orleans invented a cold-air
refrigerating machine. Under his system the air is compressed
but is not condensed to a liquid; hence it is not so practical as
the more modern systems. At one time it was used extensively
on ships on account of the absence of obnoxious gases. This
system, while mechanical, differs from those here classed under
that head.

352

MECHANICAL REFRIGERATION 353

Mechanical Refrigeration.—The underlying principle of
mechanical refrigeration, that of the consumption of heat in the
vaporization of a liquid, is not a new one. In the hot climates of
many eastern countries, water for drinking purposes is kept in
porous earthen vessels so that the wind may evaporate the
moisture as it oozes through the pores of the vessel and so cool
the water. In Arizona, and to some extent in Oklahoma, the
farmers cool their cream by wrapping the cream can with a
suitable cloth which acts as a wick to carry up moisture to be
evaporated and, in so doing, absorbs heat from the cream in
the can or, in other words, cools the cream.

A more refined and very much mote effective application of
this principle of cooling, through the vaporization of a liquid,
is made under the modern system of mechanical refrigeration.
Under the Compression system, which is explained in the chap-
ter entitled, “ Cooling Facilities for Creameries ’’ the two sub-
stances most commonly used are anhydrous ammonia and car-
bonic acid gas. Professor Carl Linde of Munich invented the first
ammonia compression machine in 1873. The carbonic acid
machine, also compression, and copied after Linde’s designs,
appeared in 1880. In large creameries and central cold storage
houses in this country, ammonia plants are much more common
than carbonic acid plants, although on ships the latter are prob-
ably in more general use. In another system of mechanical
refrigeration, what is known as the Absorption process is used.
Under this system two substances are used, one of which remains
a liquid and absorbs the other at ordinary temperatures. One
combination is that of sulphuric acid and water, and another,
water and ammonia.

Benefits of Cold Storage.—Mechanical refrigeration was first
introduced into the United States about 1888. Its general effect,
however, upon the storing of food and upon the market was not
appreciably felt until about r9g02. Cold storage is of great bene-
fit to the public as a whole. As to the consuming public, it
enables them to get perishable food products held over in many
cases from the time of high production to the time of scarcity,
thus establishing a greater uniformity of price throughout the

354 COLD STORAGE AND BUTTER FOR STORAGE PURPOSES

year. The producer of perishable products is also benefited
from the fact that he gets higher prices during the time that he
has his largest supply, which he would not be able to get if such
products could not be carried over.

Prior to the general use of mechanical refrigeration for cold
storage purposes, various food products sold at very low prices at
the time of high production. This was particularly true of butter.

A. R. Loomis, of Ft. Dodge, Iowa, told one of the authors
that at this early period he was able to buy several carloads of
creamery butter, whole-milk goods, at 11 cents a pound. Certain
seasons of the year are now designated as cold-storage seasons.

The season which is recognized as that for making butter for
storage purposes is the period extending from the la‘ter part of
May to the first of July. This is regarded as the storage season,
although some butter is stored’at other times of the year as well.
Practically all butter, however, is stored during the storage
season, for two reasons: first, there is more butter made at this
period than at any other time of the year; second, the grass is at
its best, and the conditions are more favorable for making good
butter than at any other time. During this period cows are
usually milked outside and there is less chance for contamination.
Hence, the best butter of the year is supposed to be made at this
time.

Cold storage brings into the market many dealers in butter.
They are willing to pay good prices in the summer, taking chances
on making a reasonable profit during the fall and winter months,
but in this they are sometimes disappointed. In various states
laws have been enacted to regulate cold storage and prevent the
possibility of any individual or combination of individuals
cornering the food products for the purpose of forcing prices
beyond what will net a reasonable profit.

A general agitation was started throughout the country by
women’s clubs and other organizations when food prices were
extremely high. The impression prevailed among many that
cold storage was responsible for hoarding or cornering of food
products, but investigations by the Federal Government showed
that hoarding was not the cause of high prices. Nevertheless,

COST OF STORAGE 305

the agitation became so pronounced that both the Republican
Party and Democratic Party had planks in their platforms asking
that laws be passed by Congress to regulate cold storage and also
demanding a limitation of the length of time that food products
should be held in storage, with requests for branding the same
as storage products.

Cold storage has undoubtedly been of greater benefit to the
farmer than to anyone else, as the fruits he produces as well as
his poultry, meats and dairy products go into storage. If it
were not for the fact that these products can be carried over from
the time when there is an abundant supply to the time of scarcity,
very low prices would be paid for them. According to the design
of Nature, milk, cream and almost all other products can be
produced more cheaply in the summer when grass is abundant,
than in the winter months. This is an economic problem with
the producer. There is no extra labor involved in feeding cattle
during the period when they are on pasture.

Cost of Storage.—The average length of time that butter
is kept in storage is approximately five or six months. Very
little of the butter that is held in cold storage belongs to the
owner of the cold-storage plant; it is held by many people
distributed over a wide area. The cold-storage owner rents
space in the storage plant to dealers for storing their products,
and he might be termed a landlord renting out space.

The charges by the cold-storage companies for the storage of
butter are usually about one-fifth of a cent per pound for the first
month and one-eighth of a cent per pound for each succeeding
month. To this must be added insurance charges and interest
on investment. For the purpose of completing the data for an
estimate, it will be assumed that the average price of butter for
storage is 35 cents, and the interest rate 7 per cent. On this basis
the cost, per pound, of carrying butter in storage for a period
of six months would be approximately as follows:

Storage charges, including insurance..... 1 cent
Interest on investment... .- stole SOS naa 1+ cents

—

10) 02) Ee een eee ek AUS \ See 27 cents

356 COLD STORAGE AND BUTTER FOR STORAGE PURPOSES

Varying conditions, as length of time in storage, storage rates,
price of butter and rate of interest, would, of course, modify the
above estimate. It is a fair assumption to make that the cost of
carrying butter during the storage season will be from 2 to 23
cents a pound.

Should Cold Storage Butter be Branded?—A great deal of
butter is kept in what are known as coolers by the butter dealers
or merchants. Such butter is termed fresh butter until it is
placed in cold storage plants. There is a bill before Congress
at the present time which would require all butter held at a tem-
perature below 45° to be classified as cold-storage butter. If
such a bill should become law in its present form, all butter made
in the creameries would be classified as storage butter as soon as it
is churned, as all creameries use coolers for keeping their butter
until it is shipped, when it is placed in refrigerator cars and
shipped to the dealer. The latter may either place it in cold
storage or carry it in his cooler from two weeks to sixty days,
depending upon market conditions. There are a few firms
who have coolers large enough to store two cars of butter, and
they can control the temperature of the said coolers to almost any
desired point. !

The placing of a brand on butter of this character would be
the means of causing the butter to sell for several cents per pound
less, due to the prejudice that exists in the minds of many people
against cold-storage goods of any kind. From a health stand-
point there is no necessity for placing a brand on butter or cheese
held in cold storage, for the reason that good butter will keep
for a very long time without undergoing practically any change,
if held below zero Fahrenheit.

Dr. Larson, Chief of the Dairy Division, reports having
examined butter that was kept for three years in storage and
which scored as high as 92 points when taken out. Where butter
is held at a temperature between 5 and 10 degrees below zero there
is very little danger of any change taking place during a period of
nine to twelve months, especially if the butter is good. The
authors know of a specific case in Chicago, where, owing to
declining prices and in order to avoid a loss, a buyer carried

BUTTER FOR STORAGE 357

butter over from one season to the next. This butter was held in
storage approximately eighteen months, at a temperature below
zero, and when taken out of storage it showed little or no deterio-
ration. Holding this length of time is, of course, not the rule,
as most of the butter put into storage is not held over six months,
or at most nine months.

Butter going into storage and butter coming out of storage
are both sold by grade. The changes that take place in storage
butter will depend, to a very large extent, upon the condition of
the butter when going into storage, also upon the material from
which it was made and the temperature at which it has been held.
Butter held at high temperatures deteriorates quite rapidly and
becomes rancid in time.

Butter for Storage.—One of the most common defects found
in butter made from raw cream is what is known to the trade
as cheesy or fishy flavor. The condition of the material used has
a direct bearing upon the changes that take place. If butter is
made from sweet cream, or cream nearly sweet, that has been
efficiently pasteurized, there is very little danger of its going
fishy; on the other hand, if the material used is not of cood
quality, the chances will be very favorable to its either becor-ing
fishy or showing other deterioration defects that are found in poor
storage butter.

In a large shipment of butter, made at Strawberry Point
under the direction of one of the authors, the cream used had
been efficiently pasteurized and its quality was all that could be
desired in the way of flavor. The butter was held in New York
in storage for between six and seven months. ‘The average score
on flavor, when entering storage, was 38.17, and on body 24.88;
when coming out it was, flavor 38.25 and body 24.92.

The condition of the material used in the manufacture of
butter, that is, the milk or cream, has a pronounced bearing upon
the quality of the butter when it comes out of storage. Butter
made from cream with a low acid and light salt will keep in storage
better than butter made from cream with a high acid, especially
if the acid has been developed in the cream without being con-
trolled by the manufacturer.

358 COLD STORAGE AND BUTTER FOR STORAGE PURPOSES

The butter referred to above, which was made at Strawberry
Point, was made from cream containing .68 of 1 per cent of acid,
and it was ripened with a pure culture starter; it must be taken
into consideration, however, that Strawberry Point at that time
received whole milk of an exceptionally good quality. The milk
was inspected on the stand by a man who had been engaged for
that purpose, and any milk that was sour or tainted was rejected.
At the present time very little butter is made under what is
known as the whole-milk system. Possibly 90 to 95 per cent of
the butter produced in this country is manufactured from so-
called hand-separator cream. The result is that the producer
has entire charge of cleansing separators and other utensils
that come in contact with milk and cream, and some of the
producers do not adopt the most sanitary methods. in cleansing
their separators and other utensils used in the dairy. In addi-
tion to this, there is, in many cases, the neglect to properly cool
the cream after each separation. Some make a practice of mixing
the warm cream with the previous lot that was separated without
cooling, and the cream may also be held for a long time on the
farm before it is delivered to the creamery or cream-buying
station.

To the farmer the delivery of cream involves an economic
problem. He cannot afford to go daily to the creamery or the
cream-buying station, and the result is that he holds the cream
until he has about a can of it, or enough to warrant him in
making the trip to town. Cream of this character is usually
more or less sour when it reaches the creamery where it is to be
manufactured into butter. Some of it is too sour for pasteur-
ization and the acidity must be reduced.

Various investigations have shown that butter churned from
high-acid cream has a tendency to become fishy when placed in
storage. The use of bad starters has an injurious effect also.

One of the leading butter houses in New York has instructed
the creameries sending it butter not to use starters during the
storage season. Investigations have demonstrated that for
storage purposes low-acid and light salt give the best results
under present conditions.

BUTTER FOR STORAGE 359

U.S. Bulletin 84, gotten out in 1906, by Gray and McKay,
gives the results of investigations of the manufacture of butter
under different conditions, and the keeping qualities of butter
made under these varying conditions and stored at different
temperatures. C. E. Gray, dairy expert for the Dairy Division
at that time, had charge of the manufacturing of the butter,
which was scored and criticized by McKay and Keiffer. Some of
the butter for this experiment was made at Topeka, Kansas,
from sour cream, and some at Monticello, Iowa, from sweet
cream. The butter made from different lots of cream was divided
and salted so that it contained from 1 to as high as 33 per cent
salt. It was kept in storage at —1o°, 10° and 32° F., and
placed in the vestibule before being scored, the temperature of
the vestibule at the time of scoring being 50° to 55° F. After
the butter had been in the Booth cold storage for eight months,
it was removed to the Iowa Experiment Station in a refrigerator
car. It was found that on coming out of storage the butter
made from sour cream in nearly every case had a pronounced
fishy flavor, and that butter made from sweet cream containing
light salt kept much better in storage than the butter made
from the cream having a high per cent of acid. The two factors
that gave the best results in this butter were low acidity in the
cream and low per cent of salt in the butter.

It must not be understood from the above that it is absolutely
necessary to have sweet cream to make butter that will possess
a good keeping quality. Where cream is high in acid and is free
from any objectionable flavors, its acidity can be reduced by
limewater or milk of lime.

Some of the highest-selling butter found in our leading
markets is made from cream that was originally high in acid,
the acidity having been reduced and the cream re-ripened with a
starter. Very poor cream is frequently found to be fairly low in
acidity. This is due to inoculation with undesirable organisms,
through neglect of proper care and cleansing of dairy utensils.
If cream is high in acidity but possesses a clean acid flavor and
the acidity is reduced, the quality of the butter will be good, and
it has been demonstrated that butter made from such cream

360 COLD STORAGE AND BUTTER FOR STORAGE PURPOSES

will come out of storage in good condition. In fact, some of the
leading butter dealers are now giving a preference, for storage
purposes, to butter made in the large creameries where the
acidity of the cream is reduced and the butter is manufac-
tured under conditions that impart to it a good body and
texture. The statement made elsewhere, that one of the large
creameries made 25 million pounds of butter last year that graded
Extras or Specials, demonstrates what can be and is being done.
However, not all the butter made in large creameries is of this
quality, owing to lack of care and skill in the manufacturing.
Improper neutralizing, neglect to churn at a sufficiently low
temperature and improper working are some of the causes of the
production of butter of low quality or an inferior grade.

Working and Packing Butter for Storage Purposes.—Cream
should be cooled until the fat is chilled to such a point that the
granules of butter when they gather will be in sufficiently firm
condition. The butter can then be sufficiently worked to thor-
oughly incorporate the salt, so that the finished product will not
contain loose moisture and show up leaky when packed. (See
chapters on Churning and Working Butter.)

Butter should be packed very closely in the packages, whether
box or tub, to avoid air pockets. The tubs or boxes should be
thoroughly steamed before paraffining, and care should be
exercised to make sure that all parts of the wood are coated with
hot paraffin. Care should also be taken to keep tubs and liners
in a dry place.

For preparing tubs, boxes and liners for packing butter, see
Chapter XIX.

Some butter is held in storage for more than a year, but it is
very seldom that very much butter is held over nine months.

The Navy butter is put up under government instruction and
is made from sweet cream, or cream containing not more than
.25 of one per cent of acid, and pasteurized without the use of a
starter.

The first to recommend churning the cream sweet was Mr.
J. D. Leclair of St. Hyacinth Dairy School, Quebec, Canada.
His method is outlined in a bulletin issued in 1904. The cream

BUTTER FOR STORAGE 361

used was from milk separated at the creamery and contained
nearly 40 per cent fat. After being pasteurized and cooled to
churning temperature it was held for about three hours. After
the cream was put into the churn a large per cent (25 to 30 per
cent) of starter was added and churning followed immediately.
Butter made in this way secured first place at the leading Cana-
dian Exhibitions in 1903. The beneficial effects of the use of
good raw material and a good starter should again be noted.
Leclair maintains that by adding a starter to sweet cream and
churning immediately the flavor-producing substance can be
developed in the butter after it is churned. He says that if
sweet cream is churned with a portion of sour milk or starter
the butter will have about the same flavor after standing as it
would have if the cream were ripened. Some have tried to
improve the flavor of butter by adding a starter directly to the
butter and working it in with the salt. According to the Internal
Revenue regulations, butter of this kind would be deemed
adulterated and be subject to a tax of ro cents a pound.

CHAPTER XXIV
COOLING FACILITIES FOR CREAMERIES

OnE of the most important points in connection with the
successful operation of a creamery is the control of temperature.
This control is important in the separation, pasteurization, ripen-
ing and churning processes, and in the use and preparation of
starters. Conditions are frequently such that the raw as well as
finished dairy products need to be stored. If temperature or
cold storage conditions are not under control, dairy products
will suffer in quality. Raw as well as finished products are very
perishable and are best when fresh. Strictly.and generally
speaking, dairy products deteriorate with age, the nearer the
producers of the raw material, manufacturers, and consumers of
the finished products can be brought together, the better it is.
Conditions of commerce and trade are such that butter needs to
be preserved for some time before it reaches the consumer.

The preservation of butter depends on the checking of fer-
mentations affecting the flavor of this product, and can best be
accomplished by the use of a low temperature. There are various
ways by which low temperature may be obtained in creameries.
The system of refrigeration to be employed in a given creamery
should be determined by local conditions.

Cooling Systems:

1. By the use of natural ice.

2. By the use of mechanical refrigeration.

-3. By the use of cold water alone.

1. Most local creameries, within the ice-freezing belt, make
use of natural ice. It is by far the most common method of
refrigeration employed in creameries, and undoubtedly under
average local conditions, represents the most economic method
of obtaining low temperature. As a rule patrons have little

362

COOLING SYSTEMS 363

work to do during the winter and are willing to supply teams
and help for a few days while the ice is being put up. The use of
natural ice gives good satisfaction, especially when good, pure
ice can be had within a reasonable distance from the creamery,
and a proper and convenient place is provided in which to store
the ice.

2. Mechanical refrigeration is undoubtedly gaining favor
with creamery-men, as is evidenced by the increased number
of mechanical refrigerating-plants installed in various creameries.
The reasons for this increase are due, first, to centralization of
creameries, second, to mild winters in certain sections and a con-
sequent lack of natural ice, and third, to the greater convenience
of mechanical refrigeration if properly operated.

Centralized creameries have so much more cooling to do
than a local creamery, that a mechanical refrigerating-plant
best serves their needs. Often centralized plants are located in
large cities where an ice-manufacturing plant and cold storage
plant may be run successfully in connection with the creamery.
Prof. Erf 1 has conducted some experiments relative to the com-
parative cost of the two systems for creamery use. The fol-
lowing table shows the results, and indicates the comparative
cost of cooling 100 pounds of butter to 30° F., including the
cost of cooling the cream during manufacturing processes.
These figures are also based upon a run of 10,000 pounds of milk
per day.

I 2 3 4
Cents Cents Cents Cents

Natural-ice system........... 20.1 Toe Ten iy) ait

Mechanical refrigeration...... Wise EGe i 16.9 16.8

The different columns (1, 2, 3, 4) indicate different insulating
material used, which cannot here be elaborated upon, except
to say that it pays to insulate thoroughly.

The above results indicate that mechanical refrigeration is a
little the cheaper. Its cost is quite constant under different
conditions, while the cost connected with storing and using nat-
ural ice will vary greatly according to different localities.

1 Creamery Journal.

364 COOLING FACILITIES FOR CREAMERIES

3. Under certain conditions, intentional or unintentional, a
creamery must be run without the use of ice, and without
mechanical refrigeration. Insucha case cold water is a necessity.
One of the authors successfully operated a creamery for one
season without any other cooling agent than water. The winter
season had been warm and no ice was obtained nor was it obtain-
able at a reasonable cost. There was no room in the creamery
for a mechanical refrigerating-plant, and even if there had been,
no money was available with which to purchase such cooling
facilities. The only thing to do was to close the creamery or cool
with water.

The latter method was resorted to. The creamery was
fortunate in having an unlimited supply of pure cold water
coming from a mountain stream.

This water was made effective for cooling purposes by
directing a constant flow through a galvanized iron tank in the
refrigerator. The ice-box on the inside of the refrigerator was
removed, and a closed galvanized iron tank put in its place.
This tank was connected with an inflow and overflow at the top.
A faucet for draining the tank was provided at the bottom in one
corner. The tank was made straight on the side next to the wall,
but sloping towards the wall on the side facing the refrigerator
room. ‘This was done so as to allow the dampness or sweat col-
lecting on the outside to run down the sides and be collected in a
trough, which conveyed it to the outside. A trap was connected
with this outlet so as not to let in warm air. Such an arrange-
ment gave very good satisfaction, though not so effective in
cooling as ice.

The cream was cooled and kept cold by circulating a constant
stream of water through the vat-jackets. The temperature of
the water was never above 50° F.

The butter was disposed of locally while fresh. In cream-
eries where it is necessary to hold butter any length of time, this
system is undoubtedly less satisfactory, but under the above-
mentioned conditions it gave good satisfaction.

The water-tank should never be made from wood, as wood
is a very poor conductor of heat. Heavy galvanized iron is best.

NATURAL ICE SYSTEM 365

NATURAL ICE SYSTEM

Kind of Ice-house.—When natural ice is stored, the first con-
sideration is a good ice-house conveniently located to the cream-
ery and refrigerator. When the creamery is first planned and
built the ice-house should at the same time be provided for.
It should preferably be adjacent to the refrigerator, so that the
ice can be transferred directly from the house into the cooler,
thus obviating much loss of ice and decreasing labor.

The various -parts of the building, embracing the many
details, will not here be enlarged upon, inasmuch as they can
be more advantageously shown in plans. Students are referred
to the different views shown in this chapter.

_ As will be seen, the construction of the ice-house depends
to some extent upon the location and kind of refrigerator to be
used. There are at least two different ways of locating the
refrigerator in relation to ice-house: (1) Where the refrigerator is
entirely separate from the ice-house, the ice to be transferred
and placed either overhead or on one side of the refrigerator.
(2) Where the refrigerator is combined with the ice-house and the
ice is not moved for cooling purposes. This in turn may be
arranged so as to have the ice storage overhead or on one side of
the refrigerator. The ice-house needed in connection with this
second method differs chiefly from that of the first in that better
insulation is necessary and no ice-packing material is used, except
on top. This latter type of creamery refrigerator, even though
more expensive, is to be highly recommended, chiefly because
labor is decreased, and the low temperature is uniformly main-
tained.

Reasonably high ground affords a good location for an ice-
house. It is of importance that the ground should be thoroughly
drained before the ice-house is built. If the ground is high, dry,
and gravelly, no drainage may be needed, but under most con-
ditions a drain should be run through the bottom. This drain
should not be very deep. If the area to be drained is so large
that one drain will not carry off the water, it is better to use two
drains rather than to have one deep one.

COOLING FACILITIES FOR CREAMERIES

366

“Hy
(
h

Nl

LLL A OD LLL

| Eee

K/ J
een Stude\filled with)Shavings |

Space be

Vj
i

f
4}
}
6}
6}
4}
0)
«
é
Hl
i
‘
A
t
{
thy
i
hy
iN
N
BY
i
AN
R
BY
hy
68
Hy
iN
BY
is
HN
iy
A
N
i
HY
HY
hy
hy
Wn
i
KY
IN
Hh
HY
HY
Hy
HY
HY
iN
iN
Ns
Ks

Z

LLL

WN OO

Cooling Room

ds

NAMA

(bss) Cea

\

=>>>>>——

>:

M
ut

la
C

LLL

filled with\Shavings |
bedi aaerinee

SSS SSS SS SSS SS

/\

osulation
PLAN

=

\

Space between Studs’

M
eee

{
=:

ELLE:

CS

=

a eB

4

y |

Second or Attic Floor

SSS ASG- SSS

Ice Door

LLL LLL LLL MIO LL

yj
H
4

LLL

SECTION
Fic. 129.—Refrigerator with ice overhead.

NATURAL ICE SYSTEM

(‘9061

‘epeued jo uolssIuluIoD) Alleq Jo y10dey Wor)

*‘PaUIqUIOD IsNOY-99I pu 10} BIOZIIJOY—'OLI “OI

—

‘

riaquieyy so]

$252 === =-0 YJ--== ===

SOP TaaK7ze

a=

pee
fy ‘

(poe

100 AIA

94910000 F

re APHIG MOTOH,
aie <— AU OUI)

VMVLLO'SuNLAINOWOY 40 LWAWLYvdaa
YANOISSINWOO AYIVd 3HL Ad Ganssi

W3LSAS NOILVINOUIO
SaDVYOLS G109 AYSNVSYHO

(19Ueysv,T 100M

NV1d 4OO14

08 X08

ad

IOVIISIJOWY

0,21 X,0,8T
requiego soy

szeded yooid dureq
aeded 8 .Jepiing

s ssuIAByg
2

Sulprz0g ) »
BUIPIS

SSN

410PBIOTLIJOY JO [BA

JOQUIBYD G2] JO [1A

368 COOLING FACILITIES FOR CREAMERIES

Size and Shape of Ice-house.—The plan of the ice-house

should be as nearly square as consistent with available space.

% x 6'D. & M. Fencing,

i
3° RSSSEZEE SI
* mo [BESS NNN ESS SIRE = Waterproof P; aper,
LG 1% Surfaced Boards.

\

“
% Surfaced Boards,
iw aterproof Paper,

Z M
%x6 D. & M. Fencing,

ss
bal

, j
A134 ‘Surfaced plank for
inside door, to be put in
as the ice is piled up.

LLL 2 III LS SP SIS

a Dee A pena

Doors :
UA
Ny
Kx nee vi a N Space filled with shavings
Waterproof \ through small outside door at top.
Paper. Z
7 Za
Kx 6 drop ]}
siding N
Doors lapped \
as shown, N
YY

Door Sill 2% 6 Surf, Plank 2’apart

2 x 8 Joists- at Gent filled with planer shavings
VN Joists to slant towards center of house
\' Se >

°Gravel under joists well
tamped

NSSZI,

Fic. 131.—Construction detail of i ice- -house.

A

square building, having a certain length of wall around it, will
hold more ice than an oblong building having an equal number of

NATURAL ICE SYSTEM 369

feet of outside walls. The building should also be high in pro-
portion to width and length. This will tend to preserve the ice,
as proportionately less top surface is exposed to the air.

The size of the building will vary according to (1) amount
of milk handled at the creamery, (2) whether ice is sold from
creamery, and (3) whether ice is used for any other purposes,
such as ice-cream freezing, cream shipping, etc. For creamery
uses, the only basis on which to estimate is the amount of milk
received.

For example, suppose a creamery is receiving 12,cco pounds
of milk daily. This milk will produce about 2000 pounds of
cream and about 600 pounds of butter. Suppose that the
cream needs to be cooled from 90° F. down to 4o° F. or a range
of 50° F. One pound of ice will cool about 142 pounds of water
1° F. Calculations are made with water as basis. The results
will thus be a little too high, but subsequent corrections will be
made. If 1 pound of ice will cool 142 pounds of cream 1° F.,
it will require 50 pounds of ice to cool that amount of cream 50° F.
By calculation from these figures we find that about 0.35 of a
pound of ice is required to cool each pound of cream 50° F. and
for cooling 2000 pounds of cream it will require 700 pounds. If it
takes 7oo pounds of ice daily for cooling the cream for eight
months of the year, which is about the time the cream would have
to be cooled by artificial means, it would take 168,000 pounds of
ice per year. As the specific heat of cream is only about o.7,
the final amount needed for cooling the cream would be only
117,600 pounds, or about 59 tons.

The next consideration is the ice needed for cooling the butter.
Roughly speaking, there will be about 6co pounds of butter.
Suppose the butter needs to be cooled 30° F. Granting that the
specific heat of butter is the same as that of water, it would
require 30 pounds of ice to cool 142 pounds of butter 30° F.
There will therefore be needed daily 126 pounds of ice for cooling
the butter. As the specific heat of butter is only about o.4,
51 pounds of ice are necessary daily. For eight months 12,240
pounds will be needed. The amount of ice needed in a refrigerator
above that needed for cooling the butter cannot be calculated.

COOLING FACILITIES FOR CREAMERIES

370

SSUIAVYS TIM PTE “qaede,%, H
a10}000 $3 HISIOL 8 XG yurd peovjans 9 X/ Bi]
= WAOYs 8B 109099 04 !

QUIS 0} 100],

ue)
>)
I '
gy ‘gSnOY-IsoI JO s[iejJap worjonIysuoj—'z EI OIL
V-V NOILOAS
cb) esnoy] 9d] Jo qysuey
4 Tre Ty e719 ureap snos0g meeacore NOILVAS13 3a!s
oo ath an Aa AP ae Le a eee ee “al
£ opeaD ——
ie}
pes)
o
=
EH

SsuIpIS dorq

esnoxy 907 jo
{Soy [INF 100g

*SSUIAGYS TIT parly
"WAD, FG SPUIS OT XZ

AI SI 901

oqju sAuIABYS TIM coeds

1| SUIT[y Jo esodand 914 10
qaIq Bt 100p doy sia

jooy s1sulys

P1e0q PPPS

We may count on 25 per cent radiation and 25 per cent as an

allowance for cooling tubs and packages.

for cooling the butter will then be 24,480 pounds, or about 124

tons.

NATURAL ICE SYSTEM — 371

Counting on 20 per cent loss incidental to transportation
and melting in the ice-house, 89 tons of ice are needed for cooling
the cream and butter the number of degrees mentioned above.

y 6 ft.

| Space to let
-- down ice
Outlet:-Door

2” 4ties ever

3/0" 60 door\at floor level

Il
wooy Are 9x z

Sea uu

2/% 10’ studs 24’Cen. filled with shavings.

A
Space between
doors filled with
shavings after

ice is in,

‘Fic. 133.—Construction details of ice-house.

|
|
|

One cubic foot of ice at 32° F. weighs 57.5 pounds. If x
cubic foot of ice weighs 57.5 pounds, 89 tons would occupy a
space equal to 3093 cubic feet, and would require an ice-house of
dimensions approximately as follows: 16 feet high, 14 feet wide,

572 COOLING FACILITIES FOR CREAMERIES

and 14 feet long. These dimensions are given only as examples.
The height, width, and length may need to be changed to con-
form with local conditions. One thing should be kept in mind—
it is always better to have an ice-house a little too large rather
than too small.

Filling the Ice-house.—The chief objects to be sought in
packing ice into an ice-house already properly constructed,
are: first, to exclude circulation of air through the mass of ice
and thus prevent melting; second, to pack it in such a manner
that it can easily be removed in whole blocks; third, to pack
it with material that will leave the ice as clean as is consistent
with other important objects sought.

The packing material which is most commonly used: in the
central western states is sawdust. This is very efficient in
excluding air, lasting, and usually cheap, but soils the ice
so that considerable water needs to be used to rinse it, and as a
consequence, considerable ice is wasted. Straw-is used success-
fully. It leaves the ice much cleaner, but is not so effective in
preserving the ice. Shavings are good, but as a rule are too
expensive and not available. Some use no packing material
other than ice and snow. When the blocks of ice are put into
the ice-house, they are packed closely together. A man with a
hatchet chips the blocks of ice in such:a way as to fit them
snugly together, and the small cracks are filled with fine ice anc
snow. The experience of the authors is that, by this method,
the blocks of ice are likely to freeze solidly together, so that the
ice cannot be removed without breaking it. up into irregular
pieces. ‘This is hard work, and considerable ice is wasted.

Another method of filling ice-houses in successful use is that
of running a shallow layer of water into the building and allowing
it to freeze. The doors in the ice-house are opened during a
protracted period of cold weather. ‘The bottom of the ice-
house is covered with building-paper. Water is run on top of
this and allowed to freeze until a layer of ice about a foot in
thickness has been obtained. Then another layer of paper is
made to cover the ice and more water flooded on and frozen.
This process is continued until the ice-house is filled. The paper

NATURAL ICE SYSTEM 373

between the layers prevents the ice from freezing into one solid
mass, and facilitates its removal.

When the ice is stored in an insulated house, combined with
the refrigerator, no packing material is used except on the top of
the ice. Shavings are good to pile on the top of ice when the
ice-house has been filled. They are clean and effective in pre-
serving the ice.

The cost of filling an ice-house with natural ice, obtainable
within a distance of about 8 miles, will vary in different localities,
but may be said to range between $0.60 and $1.25 per ton. The
creamery furnishes a man to pack it into the ice-house.

Source of Ice.—The ice for creamery use should be obtained
from as pure water as possible. A large running stream is always
better than a small polluted stream. Usually the creamery can
co-operate with butchers, restaurants, hotel-men, and other
local ice-users in building a dam in a suitable stream. The ice
can also as a rule be harvested cheaper by co-operation.

Some creameries have constructed ice-ponds near the ice-
house. If there is a clay or impervious bottom, this works suc-
cessfully and economically. The pond is filled and kept filled
from the creamery water-supply or from a tile drain inlet.
Care should be taken not to use stagnant water or water in which
weeds and other rubbish have been allowed to accumulate.
The pond should be deep enough so that the water will not freeze
to the bottom and produce dirty ice. The pond should also be
filled with water to overflowing when freezing is begun; other-
wise slush and snow are likely to accumulate together with dust
from the fields and roads, producing impure ice.

The ice is best when frozen from the top down. A hole is
bored in the ice and kept open during the freezing process.
Through this opening the pond is supplied with water as rapidly
as it subsides. When the water is solidly up against the bottom
of the ice it will show in the opening or hole in the ice.

To construct an ice-pond on gravelly soil is useless, and to
pack such a pond with a sufficiently thick layer of clay to
prevent leakage of water is, under most conditions, imprac-
ticable.

374 COOLING FACILITIES FOR CREAMERIES

USE OF ICE IN COOLING CREAM

1. Directly.

2. Indirectly.

1. The cooling of cream in creameries by putting ice directly
into the cream has been much practiced in the past. The
method is yet used considerably, especially where the old open
vats are still in use. Some of these open vats are jacketed
and some are not. Cream in unjacketed vats could not well
be cooled in any other way than by using ice directly in the
cream and stirring until cold. To keep cold any length of time,
considerable excess of ice needs to be used.

Such a method of cooling cream has its advantages as well as
disadvantages. The latter, however, clearly outweigh the former.

The advantages are that the cream can be cooled in a very
short time, and it does not require any special investment
for up-to-date ripening-vats, nor special machinery for the pur-
pose of pumping the cooling medium.

The chief disadvantages are: first, impurities and undesirable
germs are liable to be introduced, which injure the quality of
the cream and otherwise work harm to the quality and keeping
property of the butter; second, the melting of the ice would dilute
the cream. This would render the cream less sour, impart a
marked flat, insipid taste to the cream and butter, and produce
more buttermilk which, if it contained a certain per cent fat,
would mean a greater loss of fat during the churning process.

The use of ice directly in the cream for cooling purposes
should not be resorted to unless it is necessary. With the
best quality of cream this method is still more unsatisfactory,
as it greatly lowers the quality of the butter. With cream in
very poor condition previous to ripening, the chances for lowering
the quality of butter are not so great.

2. The indirect cooling of cream with ice is by far the better
method. With the use of our up-to-date ripening-vats, the
cooling of cream is an easy matter; but where the creamery is
already in possession of a good open vat and the management not
disposed to discard it to install a new one, the question is different.

MECHANICAL REFRIGERATION he

Some open vats have a jacket and special open space at one
end for holding crushed ice. These vats will control and hold
temperature better than those that simply have a jacket around
them. The cooling of cream on a large scale by circulating ice-
water through the jacket is, at best, a slow process, usually too
slow to be effective and practical.

This cooling process is carried out by mixing the ice and
water together in a separate vat to which a rotary pump is
attached, forcing the water through the jacket and again return-
ing it to the ice and water-tank to be cooled. The slowness of
this cooling process can in a measure be overcome by mixing salt
with the ice and water. This will cause the ice to melt faster,
and consequently cool the brine to a lower degree of temperature
‘than it is possible to obtain with water and ice.

In case it is desirable, a set of coils can be made which will
fit into the open vat. The inlet and outlet of these coils can be
connected by means of rubber hose with the pipes conveying the
brine to and from the ripener. The coils can be made to move
up and down, by means of a rope attached to and leading from
the coils through a pulley near the loft and fastened to a small
crank at the end of a shaft. When the shaft turns the crank
will also turn and cause the coils in the vat to move up and down.
In the absence of a special up-to-date ripener, this manner of
cooling works very satisfactorily.

A butter refrigerator containing a tank, as already described,
could be cooled by pumping brine through it in a similar
manner, as described for cream cooling, except that no coils are
needed.

MECHANICAL REFRIGERATION

Application in Creameries.—Mechanical refrigeration on a
small scale has been considered expensive and impracticable
until within recent years. The science of producing cold arti-
ficially has been simplified and reduced to such a practical
basis that it is now used in many large plants as well as in smaller
plants where formerly natural ice was used altogether. Where
at least 10,000 pounds of milk, or its equivalent in cream,

376 COOLING FACILITIES FOR CREAMERIES

are received daily during the summer months, mechanical
refrigeration is considered practicable.

On another page a table of comparative costs of natural ice
and mechanical refrigeration is given. It was also stated in
that connection that the cost of mechanical refrigeration would
vary under different conditions. The chief factors affecting the
cost of mechanical refrigeration may be said to be similar to those
affecting the economic running of the remaining machinery, such
as kind of fuel used, skill of firemen, style and condition of boiler,
proportion of boiler power to work done, the correlative size of all
machinery, kind of insulation and care of cooling-rooms, and
efficiency of compressor and whole refrigerating system.

Chemicals Used for Mechanical Refrigeration—The most
common substances used in mechanical refrigeration are ammo-
nia and carbonic acid. A number of others are in use, but
from a creamery standpoint, these only are of importance.
Ammonia is the most used. It is efficient, cheap, and not so
dangerous to life and property as are some of the others. Anhy-
drous ammonia has a boiling-point of 27° below zero at atmos-
pheric pressure. The latent heat of ammonia is also great.
Ammonia has great chemical stability, and is not explosive in
nature; it attacks copper and brass, but has no effect upon iron
and steel pipes. If ammonia should escape through a leak into a
room, the operator can protect himself from the effects of the gas
by breathing through a wet sponge held in the mouth. Ammonia
leaks may be detected by holding a glass rod dipped in hydro-
chloric acid to the place where the leak may be. When ammonia
comes in contact with hydrochloric acid, white fumes are
formed. |

Carbonic acid is used considerably in Europe, and is chiefly
favored because the gas is not highly poisonous; in case of
leak it does not soil contents of refrigerator, and it liquefies
at a high temperature (go° to 100° F.), and is therefore favored
in tropical climates.

Principles of Producing Cold Artificially.—The chief principle
involved in producing artificial cold is that when a substance
passes from a liquid into a gaseous state, a definite amount of

MECHANICAL REFRIGERATION Bul

latent heat is absorbed. When water in a kettle on the stove
begins to boil and passes off into steam, no higher temperature
can be reached. No matter how much heat is applied under
those same conditions, the temperature remains the same. This
extra heat is used in transforming the water into steam. If this
steam were confined, and that heat removed, by cooling, the
steam would again pass into a liquid state. We are familiar
with the coolness produced by rapid evaporation of perspiration
from the body. Mechanical refrigeration is virtually a process
of evaporation of the cooling media, during which heat is absorbed,
and liquefaction of the cooling medium by compression and cool-
ing to remove that absorbed heat. To increase the ability of the
cooling medium to absorb heat it is compressed and liquefied.
So it may be said that in any compression refrigerating system
three separate operations are necessary to form the completé
cycle of mechanical refrigeration, viz.:

1. Compression of the ammonia gas.

2. Condensation of the ammonia gas.

3. Expansion of the ammonia gas.

1. The machine which causes the compression of the ammonia
gas is called the compressor. In construction it is much like a
steam-engine. Small machines are single, but large machines are
double acting. Gas is drawn in, on the suction stroke, com-
pressed and discharged on the return stroke. The pressure gen-
erated varies between 120 and 175 pounds per square inch.
During the compression heat is developed in proportion to pres-
sure exerted. ‘The greater the pressure the higher the tempera-
ture of the gas. Part of the heat of compression is carried off by
means of a continuous stream of water running through a jacket
around the cylinder.

2. From the compressor the gas is forced through the pipes
into the condensing coils, in which the warm compressed gas is
cooled still more. When sufficient heat has been removed from
this gas, it assumes a liquid condition and is ready to expand into
a gaseous form for the purpose of absorbing heat and producing
cold. During the cooling and condensing processes each pound
of ammonia parts with about 560 units of heat, which amount

378 COOLING FACILITIES FOR CREAMERIES

can again be absorbed when it expands into gas at the lower
pressure.

3. This liquefied gas, which is still under great pressure, is
then admitted through what is termed the expansion-valve.
This valve is especially constructed for that purpose, and has
only a very minute opening in it for the admission of the liquid
ammonia. On the expansion side the pressure is low (20 to
30 pounds). As the liquid ammonia emerges from the high-
pressure side through the expansion-valve into the expansion
side, it forms a gas. This expanded gas may then be circulated
through coils for cooling purposes. From there it passes back
into the suction side of the compressor ready to go through
another similar cycle.

From the above description it will be seen that there are two
sides to the system, the expansion side and the compression
side. The compression side extends from the compressor to
the expansion-valve; the expansion side from the expansion-
valve to the suction side of the compressor, inclusive.

Transferring the Cold.—The methods of transferring the cold
to the different places in the building vary. There are two sys-
tems, Viz.:

1. Direct Expansion.

2. Brine System.

1. By the direct-expansion system the condensing-pipes are
extended to the room or place at ‘vhich the cooling is to be done.
An extended set of expansion coils then convey the gas which
absorbs the heat. A lower temperature can be produced by this
method than with the brine system.

2. In the brine system a large brine-tank is placed some-
where in the creamery at a place most convenient with respect
to cooling. This tank contains a strong solution of brine. The
chief reason why brine is used in preference to water is that
brine has a very low freezing-point. This will vary with dif-
ferent degrees of saturation. ;

Either one, sodium chloride (common salt), or calcium
chloride, may be used for brine. The latter is considered the
better chiefly because it is not so hard on the pipes and it keeps

MECHANICAL REFRIGERATION 379

the brine pipes cleaner than does a salt brine. The tables give
properties of brine made from these two substances.

SHOWING PROPERTIES OF SOLUTION OF SALT. (SIEBLY).
(Chloride of Sodium).

Ors Degrees Specific

Per Cent} Salt per 6 Weight Use ; Freezing- | Freezing-
n Sal- Gravity | Specific ‘ nents

of Salt by} Gallon per Gal. e point, point,
Weight | of Solu- ometer t 39° F BE Gg" |) delet Fahr Celsius

; at 60° F 2G; :
tion

I 0.084 4 8.40 I.007 0.992 30.5 — 0.8

2 0.169 8 8.46 1.015 0.984 20.3 = 055
QaG On 22 ae) 8.50 1.019 0.980 28.6 (0)

3 0.256 12 8.53 1.023 0.976 27.8 = 2.8)
3-5 ©. 300 I4 8.56 I.026 0.972 27.1 = 27

4 0.344 16 8.59 I .030 0.968 26.6 = 9.0

5 0.433 20 8.65 1.037 0.960 25.2 = 2.3

6 0.523 24 8.72 I.045 0.946 23.9 = 465

7 0.617 28 8.78 1.053 0.932 DD) = §.8

8 0. 708 32 8.85 1.061 0.919 DR .® = 6.0

9 0. 802 36 8.91 1.068 0.905 19.9 = 6.7
ne) 0.897 40 8.97 1.076 0.892 18.7 = FeAl
12 I.092 48 9.10 I.0Q1 0.874 16.0 = 3.0)
I5 I. 389 60 g. 26 I.115 0.855 12.2 —II.o
20 1.928 80 9.64 I.155 | 0.829 6.1 —14.4
24 2.376 96 9.90 1.187 ©.795 iD i091
25 2.488 I0o 9.97 I. 196 0. 783 0.5 —17.8
26 2.610 TO4 10.04 I. 204 0.771 —I.1 —18.4

PROPERTIES OF SOLUTION OF CHLORIDE OF CALCIUM. (SIEBLY)
Per Cent by Speciic Freezing-point | Freezing-point

er : : é - -
Weight epeciic Heat Ss 60 in Degrees Fahr.|in Degrees Cels.

0.996 I.009 31 = ©5

5 0.964 I.043 27.5 = 2.8

Io 0. 896 1.087 22 = §.0

15 0. 860 1.134 15 — 9.6

20 0.834 I.182 5 —14.8

25 0.790 I. 234 — 8 —22.1

380 COOLING FACILITIES FOR CREAMERIES

The expansion-coils pass through the brine-tank and cool
the brine. Special pumps force the cold brine through pipes
to the cream vat, cooling coils, ice-cream freezer, etc.

For creameries the brine system is the only practical system.
It is preferred because, first, cold can be stored in an insulated
brine-tank and used at will without running the compressor.
(In case of a prolonged stoppage due to some accident a brine
made by a mixture of ice-water and salt could be temporarily
substituted); second, less ammonia is required to charge, the
system; third, fewer couplings and less ammonia pipes are
necessary. This latter would decrease the danger of ammonia
leakage and cost of pipes.

CHAPTER XXV
ECONOMIC OPERATION OF CREAMERY

INASMUCH as it is impossible within the limited space of this
work to enter upon a detailed discussion of the various principles
and practices of operating boilers, engines, mechanical refrig-
erators, and other creamery machinery, only a few of the chief
factors common to creamery practice and affecting economic
operation shall be discussed here. For more complete informa-
tion students are referred to works treating specially of these
phases.

Firing the Boiler.— Much fuel can be wasted or saved accord-
ing to the completeness with which the combustion occurs.
This again depends upon the manner of firing, upon the regula-
tion of the draught, and upon the kind of boiler. The fire
on the grates should never be too thick nor should too much
coal be loaded on the fire at any one time. A thin, even fire
permits of a more complete combustion than is possible when
clinkérs and cinders are allowed to accumulate on the bottom of
the fire and a heap of unburned coal on top. By this latter
method of firing, the grates are likely to be injured.

To get the most heat from the coal the draught should be
regulated. The combustible part of the coal is of two kinds:
first, the fixed carbon, and second, the volatile matter. The
former is the coke or the part of coal which is seen on the grates
as a mass of glowing fire. The latter consists of the gases which
pass off when a certain temperature is reached, and which, when
mixed with a certain amount of air at a given temperature, will
burn. The heavy black trail of smoke seen rising from chimneys
is partially wasted coal. If the grates are choked with a thick
fire, no air can pass through, and the volatile parts of coal pass
off without being burned.

381

382 ECONOMIC OPERATION OF CREAMERY

Burning Wood or Coal.—In some localities this question is
of minor importance, as conditions may be such that coal only
can be used. In other sections, where both are obtainable, it
is of great importance. The following table! shows figures
obtained at five factories in Wisconsin where soft coal was burned
and five others where wood was used.

DAILY FUEL USED AT SEVERAL CREAMERIES

Pounds oF Milk ie Bounds ie Cost of Coal |Estimated Cost
Skimmed Soft Coal aoe Abas
per Day Burned cat eee
3,500 500 $3.55 $0.90
8,000 400 3.00 0.60
23,000 1000 4.05 2.00
6,000 300 3.50 0.50
5,300 500 3.15 0.80
Found: cr nk Cords of Wood : Estimated Cost
Skimmed Price per Cord
Burned per Day
per Day
2,000 = $1.25 $o. 32
3,400 5 2.25 0.37
6,500 fs 1.25 0.32
3,800 5 2). OS 0.37
4,500 a 1.80 0.60

These are the best obtainable figures of comparison under
creamery conditions.

If wood is burned the dryness of it is an important considera-
tion. If the wood is wet its power of producing heat is greatly
lessened, as a certain amount of heat is used in evaporating the
water in the wood. Air-dry wood will contain from 12 per cent
to 25 per cent water. The quality of coal is another variable
factor. In general, and from the table which follows, it might be
said that 24 pounds of wood are equal to 1 pound of lump coal.

1 Farrington in Hoard’s Dairyman.

DAILY WEIGHING OF COAL USED 383

The following comparative table is given by Kent:

Hickory or hard maple, weight per cord 4500 lbs.=1800 to 2000 lbs. of coal.
White oak, weight per cord 3850 lbs.=1540 to 1715 lbs. of coal.
Poplar, chestnut and cedar, weight per cord 2350 lbs.= g40 to t1os0 lbs. of coal.
Pine, weight per cord 2000 lbs.= 800 to 925 lbs. of coal.

Whether a creamery can economically use slack or lump coal
is another question worth considering. Slack coal is used very
little in local creameries, mainly because it is more difficult to use
in firing. Usually help is scarce, and coal which requires less
attention in firing is preferred. In the second place slack coal is
subject to spontaneous combustion and likely to set buildings
afire. Some, if not all insurance companies, discriminate against
creameries using slack coal as fuel. Thirdly, special grates
(rocking grates) are essential to get best results from using slack.
Fourthly, slack coal is dirty and the dust from it will lodge all
over in the boiler and engine room.

Slack coal, where conditions are at all favorable for its use,
is, aS a rule, cheap to burn. According to experimental data,
t pound of slack coal will produce about 4 pounds of steam,
and 1 pound of lump coal] will produce about 6 pounds of steam.
The price of the two will vary, but usually the relation is, slack
coal, $1.25 per ton; lump coal, $3.25 per ton. If 1 pound of lump
coal produces 6 pounds of steam, a ton will produce 12,000
pounds. If 1 pound of slack coal produces 4 pounds of steam,
to produce 12,000 pounds will require 2992 pounds of slack coal,
which would cost $1.87. The difference in producing 12,000
pounds of steam in favor of slack coal would then be $1.38.

Daily Weighing of Coal Used.—The advantage of daily
weighing of coal used in creameries cannot be too strongly
emphasized. That business phase of creamery work has been
much neglected in the past. If the coal used daily is not weighed,
a serious loss or leak may continue without detection. Firing
the boiler is a daily occurrence, and if a small loss occurs, the total
loss at the end of the year will cut short the profits.

The weighing can be done conveniently by fitting a box
similar in shape to an enlarged flat-sided curd pail on a pair of
platform scales. After the scale and box have been purchased

384 ECONOMIC OPERATION OF CREAMERY

there are no additional expenses and very little extra labor
required.

Cleaning the Boiler.—The amount of coal used will vary with
several factors, viz., cleanliness of flues, sediment in the boiler,
condition of fire, kind of boiler, steam leaks, pipe insulation, etc.
The two first factors are frequently neglected. The flues should
be cleaned every morning before the day’s run. The inside of
the boiler should be kept clean. Heavy scale on the inside of the
boiler and flues, and heavy sediments on the bottom of the boiler,
should never be allowed to accumulate. Some water naturally
contains a large amount of minerals and leaves a heavy deposit
in the boiler. The operator should learn to know the condition
of the water, and the frequency of cleaning the inside of the boiler
should be governed accordingly. One cleaning per month is
sufficient with most water. In some instances, one cleaning per
week is necessary. a al

The collection of scale and sediment within the boiler affects
the economic operation in at least three ways: First, more fuel
is needed; second, the boiler itself is likely to warp; third,
foaming or priming of the boiler is likely to occur. If scale
clings to the flues when washed, it may be removed by putting
some sal-soda and water into the boiler and boiling for several
hours. Some use a boiler compound for preventing scales.
This is not necessary nor to be recommended except in extreme
cases where the mineral content of the water is very high. ves
boiler should be frequently blown off at low pressure.

Priming of Boilers.—When considerable water passes over
with the steam the boiler is said to be priming. This water in the
steam interferes with the running of the engine, filling the engine-
cylinder and resulting in broken piston or cylinder-head. The
engine jerks and thumps to such an extent that there is danger of
breaking other parts of the machinery.

The foaming or priming of boilers is due chiefly to:

t. Too much water in the boiler.

_2. Working the boiler beyond its capacity.
3. Allowing mud and minerals to accumulate in boiler’
4. Using too much of certain boiler compounds.

THE INJECTOR 385

5. Using water which naturally contains a large percentage
of certain minerals conducive to foaming.

The Injector.—The injector on the boiler frequently causes
the operator some annoyance by refusing to work. The common
causes of this are:

1. Too low boiler steam pressure.

2. Steam obtained from a pipe already supplying steam for
other purposes.

3. Leaks in suction pipe due to shortage of supply pipe
or holes in pipe.

4. Too hot supply water.

5. Scale in injector, preventing proper working of valves.

6. Steam containing too much water.

Oil-separators.—Considerable saving can be accomplished in
a creamery if the exhaust steam is utilized. This steam may be
used for pasteurizing the skim-milk, for heating the milk previous
to separation, for heating the creamery, and for heating the water
- for the boiler.

The exhaust steam contains considerable oil and should be
purified before it is used for any other purposes. Several forms
of steam purifiers are on the market. They are simple, inexpen-
sive, and can be attached to the exhaust-pipe of any engine.

All steam and water pipes should be carefully drained in the
winter to prevent freezing.

Belt, Pulley and Speed Calculation.—The length of a belt
may best be determined by measuring over the two pulleys
with a tape or a string.

To calculate the size of a drive pulley when the speed of it is
known the diameter of the driver pulley is multiplied by its speed
and the product divided by the speed of the driven pulley, the
quotient will be the diameter or size of the needed pulley.

To calculate the speed of a driven pulley, multiply the
diameter by the speed of the driver pulley and divide the product
by the diameter of the driven pulley; the quotient is the speed or
number of revolutions per minute.

i
4
j
'

APPENDIX

LEGAL STANDARDS FOR DAIRY PRODUCTS, 1920

;
ea || Whole-
Milk Skint Cream|Butter| milk Condensed
no Cheese
States ween.
Solids
Total Total Total | Total
Solids | Not | Fat | sotias| Pet | Fat | Sotids| Solids} Fet
% % % % Yo, || Ye % % %

INENSENINE GG 6 US 'co oem None; |munici|pal con|tro!
Calitonnianee eee 8.5 13 9.25 18 80 130 YN MW G5 GF
Colorado meener a: peat ese leses 9.25 18 82.5 35 28 oF
Connecticut.......... 57S BS |eoes
District Columbia..... ee SSAC) Bais 9.3 20 | 283
Delawarern.0 9-1-2 None; |munici/pal con|trol
Mloridaiey 0 fe eee ssi None; |munici/pal con|trol
Georsian (ceo oe I2 GB. [3.08 9.25 18 82.5 |; 50 28 7
la Ely ach beeen Neate ence mies | Bag ie eu Paes Sew Apis 28 Aaa
JIG IEW Xo) Pannen Rone eee II 8 3 9.25 18 82.5 | 130 28 Ra
iki Gagnon osloods 8 Bo 13 9.25 18 82.5 50 28 77
Ineliiana eb aoe oe ssenies i 8.5 13.25 9.25 18 82.5 50 28
OW abo cc vests aiy ane ceee ene Be PS ii |eencneel |S aoe I5 80
NGATISAS YS soto cre Seton tene eee ace seas
enitickcya ieee 12 Bo 12,05 9.25 18 82.5 50 28 sl
Wouistanass see eee eee SOMA Sis wigias 8.00 18 82.5 50 28 G7]
INUepint Ree ia es cecdecsyete sees UL OWS) Sok BBR
IMigaaenGl, po6ucudod0c TOM Gielen Haers Be 3
Massachusetts........ 12.15 3-35 9.3 I5
Michizane see oe 12.5 3 ee \ 15
Muiannesota.. 5-26. 2. 13 et, WS ieSs see af 20 80 45
WMSSO UTI Pane ohteue te cesses seaa || Soin 1B6QS 9.25 18 82.5 50 28 Fs
Montanaenmcrnaa tan 12 fo) 3 eR 15
INebraskast 22:5 $2.5 sss ante 3 pene 18
New Hampshire....... I2 ee 9 18 80
New Jersey........... 12 BI eee: 16
New Mexico.......... None; |munici|pal con/trol
INewsViorksne ns: See II.5 3 ee bean nee Sicko Bhat 3
North Carolina........ 8.5 |3.25 9.25 18 82.5 | 450 28 Gott]
North Dakotasa.. 4: 12 2 He heh 15
OhiGieA ere ee tee mere 12 3 eee SO aAaitaRs 3
Okiahomanece eres 12.5 3 18 ent 28 a]
Oregonine cs ie haasie ce I2.2 | 9 Bee res 20 130 22 4.5
Pennsylvania......... None; jmunicilpal con|trol I5
IPortomRicone eae satan. 12 3
Rhode Island......... TD BS eet ea eas

“South Carolina........ None; |munici|pal con/trol
South Dakota......... Boh (ao2s 9.25 18 80 450 28 eT
Tennessee............ 8.5 13.25 Bait 18 82.5 | 450 28 FG
MNEKAS Hy a Sehcihat eae are ee 855) leee2s5 eas
Niele asec ees a cose 5 12 9 2.8 a ae 18 80 rows 28 7
Wermontinec reac 572.5 | 9.25 |4
War cantare eli er ra Seen ASS al see2ls 9.25 18 82.5 | 450 28 etal
Washington........... I2 8.75. 13.25 Ong 18 Sees 0.
Wisconsin er een Seen aleve. Te 9 18 82.5 50 28 8
\WAVOMmINE.. coecenocuss 12 ES aD shoe! SECC MI Rosters |, 280) 120 Res 3

|

1 Per cent of fat.

2 Not over 12 per cent water or 5 per cent salt.

3 Proportion of fat to total solids must be the same as in the crude milk.
4 Per cent of fat in total solids.

&’ May and June, 12.

387

388 APPENDIX

METRIC SYSTEM !

METRIC SYSTEM OF WEIGHTS AND MEASURES AND
TABLES FOR THE CONVERSION OF METRIC
WEIGHTS AND MEASURES INTO CUSTOMARY
UNITED STATES EQUIVALENTS AND THE REVERSE.

In the metric system the meter is the base of all weights and
measures.

The meter was intended to be, and is very nearly, one ten-
millionth part of the distance measured on a meridian of the
earth from the equator to the pole, and equals about 39.37
inches or nearly 3 feet 32 inches.

The meter is the primary unit of length.

Upon the meter are based the following primary units: the
square meter, the are, the cubic meter or stere, the liter, and
the gram. :

The square meter is the unit of measure for small surfaces;
as the surface of a floor, table, etc. ;

The are is the unit of land measure; this is a square whose
side is ro meters In length, and which contains 100 square meters.

The cubic meter or stere is the unit of volume; this is a
cube whose edge is 1 meter in length.

The liter is the unit of capacity; this is the capacity of a
cube whose edge is one-tenth of a meter-in length.

The gram is the unit of weight; this is the weight of distilled
water contained in a cube whose edge is the one-hundredth part
of a meter; a gram is therefore the one-thousandth part of a
kilogram, and the one-millionth part of a metric ton.

1From The American Chamber of Commerce.

APPENDIX

MEASURES OF

389

LENGTH

Metric Denominations and Values

Equivalents inDenominations in Use

Miyriaimeteneiae eiecae- 10,000 meters 6.2137 miles
Kalometer......c8..046¢ 1,000 meters .62137 mle, or 3,280 ft. ro in.
Tlectometer. 2.2 < jae oe roo meters 328 feet 1 inch
Dekametera. sciatic ro meters 393.7 inches
Mieters.... 2. 00000000 I meter 39.37 -nches
WEGiIMetens ss. ciscenc .I meter 3.937 inches
G@enttimetenanss eae oe .Or meter . 3937 inch
IMillineter: 52.0... 65: .Oor meter .0394 inch

MEASURES OF SURFACE

Metric Denominations and Values

ilectaress a aae 10,000 square meters
/NTRCE ane ee ee eee ea 100 Square meters ~
(Centareneeeee eee I square meter

Equivalents in Denominations in Use
2.471 acres
119.6 square yards
1550 square inches

.

CAPACITY

MEASURES OF
Metric Denominations and Values Equivalent in Denominations in
Use
No. of : Liquid or Wine
Names Titers Cubic Measure Dry Measure Metaine
Kiloliter or stere. .| 1000 1 cubic meter 1.308 cu. yds. |264.17 gals.
Hectoliter....... I0o .1 cubic meter |2 bush. 3.35 pks. | 26.417 gals.
Dekaliter........ Io ro cu. decimeters |9.08 quarts 2.6417 gals.
Mbibereeysen stole savers I I cu. decimeter .go8 quart 1.0567 qts.
Deciliter........ <I .I cu. decimeter|6. 1022 cu. ins. 845 gill
Centiliter........ .Or |rocu.centimeters | .6102 cu. in. . 338 fl. oz.
Milliliter........ .oor | Icucentimeter | .o61 cu. in. .27 fl. dram

390

APPENDIX

WEIGHTS

Metric Denominations and Values

Weight of What
Names Number of Quantity of Water at

Grams Maximum Density
MetiGitoneeer seer 1,000,000 r cubic meter
unital Se eee ee ise 100,000 1 hectoliter
IMitvacial craimnepe reer 10,000 t dekaliter
Kilogram or kilo..... 1,000 t liter
Hectogram.......... 100 1 deciliter
IDSRACTENIN, 5 6 oubc000¢ ro to cubic centimeters
Grams v5 heuer I 1 cubic cent meter
IDECIAMIN Gs coog00000% oat . I cubic ecntimeter
Centicram eerie .or |ro cubic millimeters
Milligram........... oo1| 1 cubic millimeter

Equivalents in
Denominations in

Use

Avoirdupois
Weight

2204.6 pounds
220.46 pounds
22.046 pounds
2.2046 pounds
3.5274 ounces
- 3527 ounce
15.432 grains
1.5432 grains
.1543 grain
.O154 grain

COMMON MEASURES AND WEIGHTS, WITH THEIR METRIC
EQUIVALENTS

The following are some of the Measures in common use, with their equivalents
in measures of the Metric System

I cubic yard

.7646 cubic meter

Common Equivalents Cempien Equivalents
Measures Measures
t inch 2.54 centimeters t cord 3.624 steres
t foot . 3048 meter t liquid quart .9465 liter
t yard .9144 meter t gallon 3.86 liters
1 rod 5.029 meters t dry quart r.1or liters
1 mile 1.6093 kilometers I peck 8.811 liters
I square inch 6.452 sq. centimeters t bushel 35.24 liters
-T square foot .0929 square meter 1 ounce av’d’p | 28.35 grams
I square yard .8361 square meter I pound av’d’p .4536 kilogram
I square rod 25.29 Square meters 1 ton (2000 lbs.) .9072 met. ton
I acre .4047 hectare 1 ton (2240 Ibs.)|_ 1.016 metric ton
I square mile {259 hectares I grain troy .0648 gram
r cubic inch 16.39 cu. centimeters I ounce troy 31.104 grams
r cubic foot .02832 cubic meter I pound troy . 3732 kilogram

APPENDIX 391

TABLE FOR THE CONVERSION OF METRIC WEIGHTS AND MEASURES
INTO CUSTOMARY UNITED STATES EQUIVALENTS AND THE
REVERSE.

From the legal equivalents are deduced the following tables for converting United
States weights and measures:

METRIC TO CUSTOMARY

Linear Measure

Meters= Inches Meters= Feet | Meters= Yards Kilometers = Miles
I= 309.37 I= 3.28087 I=1.093623 I=0.62137
2= 78.74 2= 6.56174 2=2.187246 2=1.24274
3=118.11 3= 9.84261 3= 3.280869 3=1.80411
NESTS adie) 4=13.12348 4=4. 374492 4= 2.48548
5=196.85 5=16.40435 5=5.468175 5= 3.10085
6= 236.22 6=19.68522 6=6. 561738 6=3.72822
T= 25-59) 7 = 22.96609 7=7.055361 7=4-34959
8= 314.96 8= 26. 246096 8=8. 748984 8=4.97006
9= 354-33 Q= 29. 52783 9=9. 842607 9=5- 59233

CUSTOMARY TO METRIC

Linear Measure

Inches=Centimeters| Feet = Meters Yards= Meters Miles= Kilometers
I= 2.54 I=0. 304798 I=0.914393 I= 1.60035
2= 5.08 2=0.609506 2=1.828787 2= 3.21869
3= 7.62 3=0.914393 3=2. 743179 = 4.82804
4=10.16 4=1. 219191 4=3.057574 Aa ORA G80
5=12.70 5=1.523089 5=4.571906 = 8.04674
6=15.24 6=1.828787 6=5. 486358 = 9.65608
(= Wo ge 7= 2.133584 7=6. 400753 7=11. 26543
8= 20.32 8=2.438382 8=7.315148 8=12.87478
g= 22.86 9= 2.743179 9=8. 220537 Q=14.48412

392

APPENDIX

SQUARE MEASURE

Square Centi-

Cusic MEASURE

ene Square Meters | Square Meters || Cubic Meters Cubic Feet
Supine lieth = Square Feet | =Square Yards|| =Cubic Feet |=Cubic Meters
I=0.155 I=10.764 I= 1.196 i Sy. ens I=0.02832
2=0.310 2= 21.528 2= 2.392 2= 70.631 2=0.05663
3=0. 465 3= 32.292 3= 3.588 3 = 105.947 3=0.08495
4=0.620 4= 43.055 4= 4.784 4=141.262:| 4=0.11326
BO 75 5=53.819 = 5.980 5=176.584 5=0.14158
6=0.930 6=64.583 = 7.176 6=210. 899 6=0. 16990
7=1.085 7=75.347 = 8.372 7 = 247.200 7=0.19821
8=1.240 8=86.111 = 9.568 8= 282.525 8=0. 22653
9=1.395 9=96.874 g=10. 764 9= 317.840 9=0. 25484
SQUARE MEASURE Liou MEASURE
Square Inches] Square Feet | Square Yards|| Centimeters i ‘
= Square = Square = Square = Fluid Liters = Titers
Centimeters Meters Meters Ounces Quarts Gallons
I= 6.452 I=0.09200 I=0. 836 I=0. 338 I=1.0567 |1=0. 26417
2=12.903 2=0.18581 2=1.672 2=0.676 2=2.1134 |2=0.52834
3=10.354 | 3=0.27871 3=2.508 3=1.014 | 3=3.1700 |3=0. 79251
4= 25.806 4=0.37161 4=3.344 4=1.352 4=4.2267 |4=1.05668
5=32.257 5=0. 40452 5=4.181 5=1.601 5=5.2834 |5=1.32085
6=38.709 | 6=0.55742 6=5.017 6=2.029 6=6.3401 |6=1.58502
7=45.160 7=0.65032 7=5.853 7= 2.368 7=7.3968 |7=1.84919
8=51.612 | 8=0.74323 | 8=6.689 8=2.706 | 8=8.4534 |8=2.11336
9=58.063 | 9=0.83613 | 9=7.525 9=3-043 | 9=Q-5101 |9=2.37753
Dry MEASURE Liguip MEASURE
Hectoliters= Bushels = Fluid Ounces= Quarts= Gallons=
Bushels Hectoliters Centiliters Liters Liters
I= 2.8375 I=0. 35242 I= 2.057 I=0.94636 I= 3.78544
2= 5.6750 2=0. 70485 2= 5.915 2=1.89272 2= 7.57088
3= 8.5125 3=1.05727 3= 8.872 3= 2.83908 3=I1. 35632
4=I11.3500 4=1.40969 4=11.830 4=3.38544 4=15.14176
5=14.1875 5=1.76211 5=14. 787 5 =4.33180 5=18.92720
6=17.0250 6=2.11454 6=17.744 6=5.67816 6=22.71264
7=19.8625 7=2.46696 7= 20.702 7=6.62452 7= 26. 49808
8= 22.7000 8 = 2.81938 8= 23.650 8=7.57088 8= 30. 28352
Q= 25.5375 Q9=3.17181 Q= 26.616 9=8.51724 9 = 34.00896

ST

APPENDIX 393

(WetcHT AvorRDUPOIs)

; Kilograms = Kilograms = P
PoIlpranis Ounces Avoirdu- pee Avoirdu- mich ons Leng
Grains : j Tons
pois pois
I=0.1543 ToGo I= 2.20462 I=0.9842
2=0. 3086 2= 70.548 2= 4.40924 2=1.9084
3=0. 4630 3=105.822 3= 6.61386 3=2.9526
4=0.6173 4=141.096 4= 8.81849 4=3.9368
5=0.7716 5=176.370 5 =I1.02311 5=4.9210
6=0.9259 6=211.644 6=13.22773 6=5.9052
7=1.0803 7= 246.918 7=15.43235 7=6.8894
8=1. 2346 8= 282.192 8=17.636097 8=7.8736
Q=1.3889 9=317.466 Q9=19.84159 9=8.8578
Grains=Centi- | Ounces Avoirdu- | Pounds Avoirdu- | Long Tons= Metric

grams pois= Grams pois= Kilograms Tons
I= 6.4799 I= 28.3405 I=0.45359 I=1.o0161
2=12.9508 2= 56.6991 2=0.90019 2=2.0321
=I10.4307 3= 85.0486 3=1.36078 3=3.0482
4= 25.9106 4=113.3981 4=1.81437 4=4.0642
5 = 32-3095 5=141.7476 5= 2.26796 5= 5.0803
6=38.8703 6=170.0972 6=2.72156 6=6.0063
7=45. 3592 7= 108.4467 7=3-17515 7=7.1124
8=51. 8301 8= 226.7962 8=3.62874 8=8.1284
9=58. 3190 9= 255.1457 9= 4.08233 9=9.1445

Lal
. oe
) /
-
Fl ‘
i
1%
; Fi
a
’
i
bts
oie
=> ;
nile 7
oe ay
haar ewe
7 " : :
‘ ,
,
el
*
i}
j oy
; 2
1
i a

PAGE
SN DVANOVREEPED MAraW S12 Sd ee aa le URE a U2 a SE A a 65
Acid, butryic, capric, caprylic, myristic, oleic, palmitic, stearic.............. 16
carbonic, hydrochloric, phosphoric, sulphuric........................ 20
CECE A Cuneo eachitrs evsiic) Gr 5 Oren SGN ST SRR Ce eae aan EMIS NOS] RNY ag NN yt) tra DD
NDE ETC ss chi bn Ge ROR RRO Bes reat rs Eg nn Pay thi da 310 a PR IRN 19
Ctrl Noh eAL Tobe ammete en Seater ita ee cgran de) Ae le A a ae en AN 2 Aes op Ee 127
CSUN OUND Cee eda et Le A cs ses os, Le 3 i ga eR PERT Oe , 98
LHERSIUS 6-2 et Sie a intr eer MRR at ihe he? Ft cay Givi Au ote ie ee eae nls Be Q4, 222, 223
ENGI citayao hori kes 52,8 ob A sas eevee GAR OE eee Fei nico a ae ee 04
of ripened cream in relation to richness of cream............... 221, 224
COLE FSA CENTOS) Sh a eee eR RR 10 Pal No Oeste Ls 5 237
TWSESH RS AROV Rs Fs gM MR een nt Aa) se DDD. DOB
PNelestomgo term eepet wi, 2 500-0) eee ee ec... Sen ech 37
EN Moyenanreta ahaterattl De 3 a Beltane ana eee pean ORIN (en. ay PII oe a Ma 18
éNWoyonaairavopte keh atratesiabl Le c3) 2 le dee ee eee etc Pha eee he 0) ERRNO He. toe a wie 16
Alkali of various strengths for measuring acid in milk and cream.......... Q4, 221
American Association Test for buttermilk and skim-milk .................. 103
PAM PUOLEHICEACHONT Oli Keuiers etary ekcms a meer eee sad eae eee 33
PANNGISE MELE See teria re Re Meanie Meer vauane, serccire re has amit euatetd marcy Sic! Renae at anak 59
PANS Tiptree renee nee aie estar eek ea ences a Ce ee RO ated Na Gane sue Se 19
PAO COCKEESE LOTMA Gye fet c's on Meet eaten hen, oS, SY Uae nal 97

causes and remedies for common defects in clearness of fat
LTD Gates iy ah oo 2 3 100
Bacteria in milk, aroma and flavor producing............................. 215
as a cause of deterioration of butter...................... 13
Classiiication Ole... nt) Caen 0725 6. 3 sloe Soe 61
conditions favoring development of...................... 55
desirable and undesirable in cream ripening............... 217
: kinds olsgerms found ingmailkererss tj. ss ee 60
Mumiber, of im rn aye ey yoo ae cide oss s Gaede gamete ene 62
SIZe-anGi shape! Olen. Meee cre WILE en oc tse . 3s ee 55
SOURCES Ofc ude Ce ee oof eee a teas. 3 0 a 62
uniavora ble conditionsoneers errr 4! 4.) cc s7. 2 eee 58
Belagpullesandispeed) calculation: eer eee ee ne nn one... Ue ee 385
Boitlerrcleamin sao tvasern icin: 4 ta pore mem mess Marae suis ite 6) a 384
[DUT WATT NAYES (OS Aa eee na or Seer Bie rel A Soa cise Sid cic ee cr Arne TESTS 384
‘Hilal idly. Weis SAO eRe cr unaete teeta Rech Shack 0 1 8 GA cr rane 381
WOOCKOTICOAI ORS acre yan Renae Tore eae een) tt ein eke hh Veen eee ae 382

395

396 INDEX

Breeds, composition of milkifrom various; s))-5 2. a) espe ee ee 75

Brine,:saltinevbutterswathythc = 820, eine eee eter ee aa eee eee arr eae 287

Soaleimg (GU Sramns 843 hei shbcaheh ata Sasuke ee eee ener era 300

Butter, appearanceior style Of. scar aad aera. ae ee eee ee Cr 7 ee 342
classification and grades of, as outlined by N. Y. and Chicago Mercan-

tile we xchiam esta Vinee einen th aia cal aint eter Oe 28 ACA 342, 347

COLOR OBA (2 a PARR 20S INT sais aN eee Rig a, et a 253, 341

COMPOSITION OL) 2 suhdt hetok! Meoncro ea erae suse a ee Bone /eiSls)

cost of manulacturing...52 reais cee ta sce can st eh eee 207

EXpOrtatiom Ol...) A. ain see ee eee ses pss Hens een wih 350

HAWOL OL 48 meer alee Heo. pickle eee tat Bo pinks Oa laead Oe 340

for storages. UL Ms er Ge | 357, 300

judging and eradingiote: yee .5. crete eas aes oe ee eee 340

keeping in-eneamentesitas cece lea. boa bose a katie ce eas ey era ea 296

making of ;omibarm aie ys eae Gerace, aca: eesaiee eevee eee 180

mottled: causesjandlnemedyi. 480 susie 59 ee 279

package: Styleiotes es oy. ds oa yk oes cugain ene ee 204

packing of. Ayes, inte ile etd Mol ate neon te See 204

preparing formueamketiie. oui ieieeh ie Ge nae tes S ees eetae.. ae r 204

PEMUEING OL We oa ad fds oad kee vacies nubs aeean ee aos See 209

SAlLIMESS VODs Neg nies co a ehsdt PAE MORE aga ei Os acl ee ae 342

storiig: im /CreaMmenies:.....72.0)2,. cee oe nk ee 206

fests fOr Wat ese e eke Arise al ae eRe ices aoe ae ee 107

texture: or body Olse. ers \alie. Nely Miya sentaus w4 5 lees tees aco ae ee 341

treatmenitobis 5 Voce nis ho cs Mee ies eich the acer ne 300

washing, and kind of wash-water...... IE I ede iO tn 263, 265

WODKIMOUO Lone ain Ame ky seein dsa se abet Sie cud een 291, 360

Butter-making, Historys of. . s.r noo ey ee I

Buttermilk test Of", Jae. 6. . vtec Sena We ee ae IOI, 103

TETAO Vall O betgetyyed is aoc. keel at kaleeciet ae ea 263

BIDE AG Te gue POU iol cc. c ES HCA Ain Hs ciple 6 HOS oo 'o.a'e Po os 3 13

Calculation of amoutt of salt to add to butter........................... 272

averagespercent fat: 002i cols Mend Seen is Rae eee 131

Chirrmyyrel dic o2. 3.20 ot ee en ee 135

Creamenaisine COCMICIENt a eae en eee pee enn ane 140

Givademessen tne i.) 2s eee ae 2 a ARRAS 137

OVELTUNG NE. osc vcrsc a oi as Slang Bi oat Re ee eee 133

Solid swmemialle 5. .5 0. osc cade Gece AS Oe oe ee 35

Cams) Starters. cc ARAB Rae Gitlin a's Wide Rte Riise a cA ny er ceo oe aa 238

WASMUND OS ete ce eee sale ein o's phd aE EE eo ea ates

Careof cream/vonvianmiyn. f .5.). 2. 262 oda ee Se OEE cate eee 176

Gasein in milk. conditionof.). 2.22 2. Seve eae oe co ae er 17

Centrifucallseparatiomjoieream).\. > 506. yeee) see ec ee 154

Chumy ‘keeping imseoodrcondition..- 55-2 a. sec n ree eee eae

@humn yield, icaleulatiom¥oie 2.000 eee aye ee eee 135

Churtied mule samplings: e405 022... = poe iene ere eee 122

INDEX 397

PAGE

Ghia ATMOUN baton ae yee Oy meal een a A ie ae 247
(CON Orn Rs eera ea ceaiionle, cele otic ala eh Oke ek Se 253

CON CILIONSia ThE CLIIa eae caday, mune ny RRA Telus Sodom LUN 240

QUST HYOp AT OUTS te Pid eb hen tic, cas aR AR A oe 239

GIQEIRES: CH INYO As eo anc esate) Ula Ee ge aennra amen Mn ae 248
dititculicatises and sremed ylon amen mans aka ee 258

MEXCO mc Wer man OUSOUT Cheats aye aMA ess eS. 258

MALE ROMA CTC ONGLON. ss.) ais eee Ne beat ose lL 240
TICMMEssROIMCLEA MINTO LA, Wr... We Aen wee Tce ici avn dose 245

SIVAS OLE ALISIUUIES, Vo eos reine ie le ee a 2 252
StraminoavoMereaimmprevaols ts risers see |. >. lace 253

CMe FAUT ey macro kweli: Cle sPN eS Meron 10 Scns lca ova ms shanaust op baentigeloae ee adatens 240

WAMEIN 10) SUWODs5 on casuvdoscsesocce PSPC his r ios eehGey See Oca a ep ine 255

(Cribale acral shove raul oe aie on. a lobotass gc uci trgt aaa Oe ean OE ene 22
(COOLS SAUCE ae, Sloe is ate lo eg. oe a SN 352
Den ehits Of. Sane a ee eee Mee oe oss lig te A Ula 353

COSEIOT. 3) 0527.5 Nee Nema ES So he Sale a 355

|RULSEVOV (0) BARD Cater eSere ol' oc:oro.s'c o's 6 4: ¢ ee ee Mee ee ytd 352

mechanical Teirigerationyes- ee aye. 3 Ao ee 353, 303, 375
Coldistoraze| butter should at be brandedy me ses... eee 356
(Coallove ovate Weress coe, are anne ase cL Lien Le mee a CU Cone 253, 341
Colorinapma tbe reins wall kee crs er ert oh ee gs). cg en DD, BO
Wonanierclalystantersisy yer a) ens relic e ce RENN Se! chek rete ela 227
OLEAN GUNG WOO vase Sess ceeeuedacusc doe gue: 230

omiposite:saMnplesis Meets vy Genteye\a kIT UAE ed a eae Mah ih Acc Lila Gee, Dale » 127
aTraneEMentwand care Oles5 4am Geet ie ee ene 128, 129

PRESeHVALIVES MOR Sul Heptee Amn anes iF AY A aL oe 127

Sammplingvappard cusstOn i. weeewae nner.) | eee ees 122

(ConTPOSIEIONy OlMb WELET errs or. erates, cscs ee RRM eS cas. x. os & ence 309
ICES ANCL ES sASet Opis ce) eit nM ac, 0 oe 300
analysisnthintyavearsiacon Seer. Ss eae ee 315
Giscolostrummil ace ee, as. | 65
COMPOUNGstLOn MN CreAsin gayle ld aaemee eee ye.) ae 310

CONtTOliOn MOISCUTE 0. .¢s aes... | de 312
Oiidalinygsalllts:cot.2 ha eee IM arn Soto oe ee ee 278

different kind Sof millkeye ere fs 5c, re cody. 's » cnn 5

Need stor Tesla ONS ae eae ee fake. ee eee 311

Ofssalliy smc... Cnl sre I eee. ee)... stam 66

SEPATACOT SHINE): Lea ok sh. a 166

iMberculOuSti lke epee eek. eo 73
WentivousmeL sod on pasteurization aaemen Eero! |, jo eee 208
H@ooley27methodtomcream)separationeere rare ene ce) 205) | een 150
Cooling facilities; fommereamenies 5 cara Saaem ei eo cake cca en lan 362
COOMNERSY SLC IAS eee gue ov te ss 5" Rae 362

mechanical refrigeration...................... 353, 363, 375

TAPOIOTUNE| TGS aera a ners cS iBe0) cbt eee ae OO a ea ee) 365

398 INDEX

PAGE

Cows;ibreedsiok: sctcaisale a0 coo oe ee ie RR ene ee Fis
Cream,jacidity; of, forichuminior sag n pene oe ea eee ee ee 224
Garevot; jon: farm): 4 eels die a he Ce eee 176

eftect of cleanlimess oniquality;Olseeraern een ene anne nee 176
Sradin gO ss ease ot.4 Aen ee ee ee 93
methods ofdisposiig: of Lees soe te een ee eee 179
neutralizationioh 0 oe iye see ee 2 ee 184
pasteurizationiol...tcn% 0 sys e ee eetele oe ae 201

SOUT, dahon sa seacate errata Ree ee eet oie Snes vice Gee 189

Mpening Of: Wes conve k 6 ease cee Se ee eee 215

Samp lin GrOb sd cps. names nisin cate beee eee ee ane! eal eter eens eae Dears 118
Creamery. sewage disposal, 1). Yas... 2s get eh ot eee 299, 300
Curdy specks: Invbuttér cist ys oi aks eee a ee ee 285
Meep-setting system on creamiseparation se. ys-- eee eee 150
Defects found! insbutternpee ees. eee hee eee ce eee ee B28
advancein lactation!.-2- caer soe 329

cheesy Mavor:. csc ere sce oe ee ee Cee 324

faulty factory conditions, -.--).--....22..-.. 998: 325

feeditlavOrss eee eee Sere eee HR a ac 327

LAST ak hie tie ead ta sen eee ee ere ee 336

flat. or insipid flavor. +2... 4.0. oe 323

flayorsiby,absoxuptionan ee ore eee eee 324

ParliGi., .Ous0 5 Mee uk oy Peas eee 327

metallicthavion ea /<5 2s) ee ee 335

Sour flavors. syle) ee ee ee ce ee 325

Stablé flavorsijin-i.s-scthe 3 ante me nas eee 324

tallowy flavor’; 08 AS ele oe ee tn eee 332.

Difficult churning, causes and remedy...........................--2-005. 258
Dilution, effect of, on creaming........... a Re MER ETE “ee pe 153
PDISIAFECHATIES, 3 cs. creeR ee Aye cola vais a= la Ses ee Ee Tee cE eRe 1 59
Blectricity, effect ofsonjeerms in milkaen see eee 64
Enzymes in: mail reine) oi. 3.5, os be aye eee ee eee eer 22,54
Classification : .....'. J.cieteseee itll ee see ee 54

efiectof heat on. 5.55 28 ol Ce ee ee ee 41

LOSES OT fi! 2. aie lee ca eee 42, 201

Export butter: Ac mpemeeie res! oi): ok ose ilendteng octet te ae ROS eaten ae se ee 350
Farrington stest:,, ea pttee oie to's) oe ss oS). cee eS a Rees oe ee 223
Fat, inbutter:.2 ieee ce si) eos 25 ald ae ee 309
WT Ka res Re te2 2d Jenlai ds Re Ne 8
COMPOSIFIOM OF eo. ss and Able Gee 15
COndiTIOMVOR i Wii... anes ae cove oe Sen Oe ee eee II

effects of ecnwironment.. 7. ..S0 2 eens 2 eee ee ee eee 80

heaton’) <2. ose etn Se one Eee 42

various feeds on composition of..................... 242

INDEX 399

PAGE

Ha amg kas PAY CELI ES) Ole 4 ka LAA ee AGM de oe oiler aete iNee Se ae)
ely COLIN Gy TEs: rae an oe ton Seen ee ee a (Rem AS, 15

(aoXe Etaves ore aN ACC Se 8 eemene ata aias Gntic hints eGitok oe yen EMM eS be IO, 14

membrane enveloping fat globules........................... II
Microscopical appearance Ol. asMn essen Ne le jase es 9

TOYOTA AONE EM Kye are oe PRR aes as A EEE Py Ch Se 14

paying for, as compared with fat in cream.................... 143

j OVO) ISTE IAS COV soe re wile ee ne Mp ene op th SANE a x cuca Seren cate Shae 10
SEPATAlOMNOly see ie esc het Riera cece Pere secd See 149

SIZePO MeO UES He. nt ey ee enema Ce, ges telat rae ee 8

testingeforser ae een tis aaa ey recto es. meee 98, 99, 103, 107

B90) EN 3 cts V eek UN at pep egeer ete ol oa ee ERMA nh aN SK 13

Heed Sweitects: oi jill kee A eee, hey waa aera ence rath LOPS 70
Henmentations. detectionvolyie.c 0 ese eens as oes ss ae ee 67,94
VATIOUS: Kin GS) OLE A erat Cree INEM Ite os sc. asc epee eee 67, 71, 73

Ferments in milk, classification of enzymes....................+0002-00-- 54
favorable and unfavora’le conditions for.............. Ris. SS)

WERT Tate ces eye ee inet o> Sa us delete ere tc ee RERUN oS, a ee 22
Bilitrationno fawiatente sas svc tcean one seat ee nee ee eens ess. ae 266
metodstandketeetstoln eel arr selene 266, 260, 270

HlavOrsvO tb Ubteramn eras wen tice can. 2S RSs eaten meme haart Le AI pe 323
il cape Wen res pore neg ee) 2 8) Reg UR Tee 20, 32, 40

Hood storibalctenidrs ogee 5 facut edviees Ales «cae eae RCE RRE e Ge oe cRe REED eee 5 §5
Roma, tor callouleyanare Clnoiin will, oo 55 cs cco vc acon bodsousseuocccseoess 135
Gheam-_ralsinescoehiclen tye aes enn yee eee ren 140

Given cl Sirens et cetera tg ee hoy eeu A eer 137

ONSET TUN are ooh ep 1 ers meee Re OPN WER BRS Pree cninee}

Solid stimermll key eee teeta ne aan IN 35
Brozentmulkeeiectsroinireezineannene some ae toe eee = DAR
Galactase merrill ewes er eee See 2 eee eM. Saocc. shh sue 3, 2 22
Garlictremoval- ofp tlavotyas seps sss che OE eo eo ee ae 327
CRAVEN Clits ato o abe oe gue nde TP. ee 328
Gasespininailk eliminating. V0. Py ceria hanes ok sa. dk ai ee 21
kamdsran disources: Olt were Ne) ss esotpd soc oe eee 20
Gerbentermentationntest<1o. . ct. sei een us Glo aces dss Hoes 95
Glasswarestor babcock test... 5 ee ec is Hoa dete eee 99
Gradimepmilkiandscreamsa- 925 on sees ee cs in. oa ere 92
Craviiy separation different systemsiOleemr ye hen... <.-... +... . ance 35, 40
Grittyabutlensaarre etic tl ee Ee te oe oo eae op Rae 278
Heat, effects of, on properties of milk..................0..00..00 00.00 eee. 38, 06
heatineemila previous tors kininming ee - PPh 356s ss ened seme eel ee 145
Ey draulicemethadkol Separation er tns cs seems iyaict sss 5 alc econ emre es ote ete 153

fy droseniperoxicl ess 5 aya Aarne ane er mtermmrete NN Do. 2 RG Bee ee 202

400 INDEX

PAGE

Vee; for cooling cream), i.e. ad eo ie sein > Seon eer ee 374
bE) tod =) 17 51(0)0 ee ee eS OA MENrE IRA 513 clodichaepladic’S o « 365

1 cht 1¢,X0) Ca RR ane Me Aran hectare OUD ET oh 6 ‘alo ited ba toma or 0-9 ¢ 385
Judging and ‘grading butter... 3.002 sf. achat scene sia. <i «ht 340
classification: 25:54. iseaien 2 oie oe aes age 342

Chicago: Sasi: sa.) 2.3 dase ee 347

INew Work.5) «shee eek eee 342

export, butter.gs.s\ca)s sac 6s aka eee 350

manner ot judeinyey ys. eee eee 341

standard! forsci.o0) o2 4< sce ago cue ee 340

Keeping property of butter....... eSNG aide) aoa abe 188, 360
effect. of saltsons.2 4. 4.442 ass eee one 273

actation) period, ettectroieon milk and fates. a2 scree eee 78
Lactochrome dm milke pepe Vass c...18 eoirsiee cee ake ae 22
Lactometer, comparison of scales on.... 2.2.0... -. 02s eee ee eee eee 35
|DISCR(0) Iateer Hc) 1 Ge ne RENO) Sree 62! Cae te Gin o.oo oc 33,97

Teecithuiny tm miles 2 eens 2 oie ak ac un ee ed ee 0 22
imi, its (uSe 1m! (Crea mMentlesy 22 2-7) a eee: 4) 261
Mammany gland): description of.-9.- sn. 6 se. see acne eee 23
inflammationvof. + a. 25 65 fb cose atioes seal el eee eee 30

Marni’ s teStae ci ticle a iiis cisin toate Rate A alee ae ee 222
Mechanical refrigeration........................0-. ai NEL Nias cra 353, 303, 375
Membrane enveloping fat globules....................-00 sete eevee eevee II
Mercantile Exchange, New York and Chicago grades of butter.......... 342, 347
Metric system of weights and measures................... 002-000 esse 388
Milks satpniormialil Salary. 5 La 203 eee eee ce te 65
appportioningyskimmed..... (01.0.2 ee os eee ee 124
Gt Gr ss cle ee cee sw ned eee te a 69
bloody.) ab ye cw as » Aegina sauears a he eee ee 67

blue andivellowe fia). i05 5 sa baeaithe i bee eee 68
classificationiotter 64.0). << «0 s.e2eend nen cote ae a eee 3
COLOSt rum A else re ees cw, cooley eee Rapa een 65
COMNMPOSTEIOM eh Sus. 6. ie yoke a Gents! Cialis SNe eee es ae 4

of, from different animals.................-2+-.+.+-+0-: 5

GeMMIUELONOD ese ie mee ees bad ccd Lb eee cyte eg 3
effects of thunder-storms on souring of.............-.--.+-e-0++ee- 64
Partin Sketrrim ede tate ge cevaius soso a al sta aie ee ee ot 1 150

POV ETS Fic ee ted ease oobi a ae GAS DA RC REO, one ee 30
fromybarrenlandyspayed (COWS. s- 4s aee eeees leeee 72

from) cows a)lonestime un milkes an. - sees ae eee 71
PVAGIME OF sie eG iis. cS sie bales. av eles ee eyteeamnal easter eee 92
NECESSity Of COOdE sa. ac- dsisieio Ge okee ee ee Pe Ee 117

properties of, physical and chemical. >. 0.0.2 - 200-5 eee Be

INDEX 401

PAGE
INIT, TROY ON o's os EEE orcs olsttle, ou ale aces ein sage ie ait aR RANE Rang ee EN NE 68
SEI 5 3. a &: ce ANRMO ot rom seals Seb yc, Aen BE Heed es Ue UPR 66
SURAT SRO LMREE os ANS acon LE aN LER VeRO, eth oO yt 118
IROPASIOL, CleiwuMeGl, AAG! SOW. vis ccc hcoceoaeoecoeocone: 1220923
SCCheMOnBOlE CONCIt ONS alle Gig pis wee enya cee ene 28
HITE OTIES Sey felis nics 5 Uae ee Ea PMP PLE OURR = SUEPe a ae 26
; IHeCgOT GEL. CONS 3d .0'a a Gat ee RO AS Ce RRR ee Pet oh Sah ne eaee a en G2
iS] OXELCH ACC: (OTRAINVATIENY?: GUI inact Becher nee oe Ps a cs RR MERRY 33
Gy OVSTORNIKOSIOVERNE Cll oc oc! aig aM ty Rene REC EAR a eee IES Ne ok 38
VARMEN AOA win Gwe Oi, ANG! CAWWISES, Goes oss acesenoesnsesececoees eae 74
WicULET Ol. tate pert rmrenunnre wate ie cr Sis dren Seve Win iS ott Geet alleen 6
Milk and its products as foods............ SFr Rey eay e vken. deta ee Oh A a 43
bprological¥classiicatione an aan ee 45
ASTANA? CIS ee ae 46
Protein Sees 46

unidentified substance
al Tan WANES soo oo oe ayy
Ghemicalaclassiivcaitons 2 |e ieee 44
Villain einen enc, Osi. ./\.:t. koe eR Rea 3. OEM eat 75

, AO MOES PCO) hes ME Lee ee DN RNA ct) ee ec Mert ek,

. Moisture control........... 5S cE eR RE EN is.) ie) Cea Pate ee)
factors, that} aid sin ee yet. Reape ss CPN Oa een 318
CHSTSTUSY CO} is ORUUCTUT eh ch reece rh ca Ree TE On SOE 3 Cr con Uae RUSTE Sic a Rey de 203
LOM Kay si ORULE eS saber eee aba lara ue asta Reade iota omer ce SR AR as oon 304
OINW OU E LETS 6 Cate aleve geet MN teal iy 4 ae ROR a te cet hair Beles TUR AeA 306
COMGMHOMES iA WOMANS WO BWOWAM. 524 oaccececcoaveccburcscc 307
GISCOLOTALIOMS cetera peti ype) 1 EIA otitis, MEP ik "ocaspae: 307
DPLOPACA UO DA eee eS ee eRe. es Lees ak 307
SOURCES OL. bse e eh canee’ or OA aM) on. cies. eM a a a 307
Montes causes:on mime utter .tsvsacest cai cess ete ols cl fe see tees. 279
IATA SSO Fe ceg see bon? Ws ou Unt er Bet. <*., Sih Eee 281
DLEVENLONOLSS wae et ce a eR oe ene a 5 eae 284
Natiralustanters reparation Ole ..chitor see =... se one eee 226
Neutralization, “neutralization” of cream...... Rs. ale oe een 183
neutralization of cream for butter-making................. 184
NeuLral izations principe. Oimmmemenaee «.,) lsd else a= asia eee 183
Othermeutralizers:.- Agee 6. alate we'd a at tad ae 199

pints of lime mixture required to reduce acidity to .25 per
Gomes (ale) hee a ete elbe Sw egal ee 106
the preparation and use of lime as a neutralizer............. 192
Non=V olatilettatsmreny vs. ..0 400-1. ce PPR ene eo cians ss.» «a ceemamtieen 14
EN tae] Simaatmp rales wep sincy ial eeceaa eMRCe. hse eps 2 Ferg NTs bles 22
OSE para to reer cs vse Pesan Tae NT PUN MARR oho)... apdeden aki sya teeter 385
Olein, effect of variation of, on softness of butter..............0.0..0.005. id

Opacity COVE TEU heey aioe peace c SUR al sa Un, 2.0 eed er aE ey 32

402 INDEX

PAGE

Overrun, demmitionvand calculation Opens ects sen ane ie ners asne 133
fAGLOTSEOVEDIIMG. tos 2s, Bhavan tates etre Ae emer eS ceer 133
what‘shouldpit ibey..c<. sasdea0 Sone 8 Lek ee ee 2 cose 135

Packing. buttery: \erecic alec ct ts ca Tere Oe Ae en coat ae 294, 360
kind and is try ey ot py alG aloe aie ee eee ele eee 204

TOR SLOTAR ES... 1 ck crshn eid aE es Ale lols uc te er 360

treatment Of tUlbS pLeVIGUSsLOR mer ele nt i 4 7l. eee ee 300

PAUIAMEUINS, 6 2 oc lal acca s asses ror ahaa ae at a Nas DRO d Ale Ns (coe ind eg ae er 14,15
Paraftining. of tubs. aye jet eee ee res ts. 302
Parchment paper, treatimentolean s.r iss) 1 es eee 304
Pasteurization, advantagesiOne jis. 4e)) ee ean. e | eran an eee 201, 214
COSE Ol yreEnenysin is Rite itweete Weed 5 eo ihe oe 212

GEeMIGIOMN ee is Ske Sei anki eee eee 201

disadvambagesy Ob, (5.4.4: caked 5. one Rae Cee eee ee 214

Pood mullsandicream! umpoctant.. 97-4 eee 204

MNEEMO SHON cise leas, 04-5 Oe aay Pee pee eh ee ec ee 208

EANItAb OMA Ate ees eee ee er 206

StorchwMlest LOI: «2c, chips ea eet oe ceed Ameen, © ia ae 201

CeMaPeraeuress b, .6c61 De pit em Ieee Ce nee nee 202

Pasteurizers, durability and efficiency............ er IE Eo ooo ac 210
Paying for fat in cream as compared with fat inmilk..................... 143
Broteidsintimilk; asmycause of maotiles! mb Miter: ay. een 280
KARIRNO ES i eS et ae ARO bree Vda edie oh ome er 16

Quevenne lactometer! Asya ig Siem optic Anis. co ae eer 34
Receiving milk and icreaminys. 6.05 cage ceed orien See ce ae ne ee 92
Richness of cream from centrifugal separator...................-..--+.--- 81
eraVvity Separation... i245: a. 4asee ae eee 151i

Ripening. cream) Getmiiton..'. .. sere ae eee eae eicy eee eee 215
depnecrotaciditystosnpenkton ileal cen tte 224, 248

kinds of acids produced from..................... Pity oui, 2Y6)

TMU MS LAT LET, Wilt AG TGe Ue eee el een ee 221

ODJECESKOR ss 6 ede UB tela a tanleny et asa ie ne ee 2uG

LEMUPERALUITE! oss, <. cusenon' a Cuetuel cle chard ana nee oe nee 220

CESES HOMACIOIEY. | ou... e ann ol a ete ae ere ee re ea 221

Galt, ‘as’ a Causesolom ottlesmis 2.2 25'1 5 Saha ist. ire ska alee tate tt ae nee 279
Compositionvot American and! Danishiy snes. ee eee 278

condition of, when added to butter........................ 277

effect of, on keeping property of butter..................... 273

Temovallof beter keys teeneenen 275

TU) TREN OKOVOL (HO) \WWENASS aH [OWL Se os coo caaononceaacusaovcspoouc 275

Ratael auaval ovale Gigs 4 occu coe cocucnssncvsassobuosnecce 277

undissolved, in butter... . :¢0/ au Sa oe eee 278

Salt test; -chemical#changes.....). +... 21) iau mene inte ee ogee eee 288

features Obie Mets fo chs na cnstl8 Oot be BOM Gis uen NES tt cin teat 289

INDEX 403.

PAGE

‘Selle (ee1%, (UTMOCET TORCHES et aN is PR RCs JE: RA A 288
(20) STEN PNR ce ies PGRN, Een, <r ee i Oe Ne eA Rr 20900

Salting ouctemamounts Ol calt tose a) see eee eee eens see 272
effects of, on keeping property of butter.................... 273

PLUG DOSERO LSA ct 008 cs ft nk gtd emer at A AB Nr ea Nn 272

LUI, LOOT OVESSI eee age eee enna ee crite onan alae AR Ree Aes 287

SAP) ES neve lal oC mmm MEN Prete) 10a. ciate Rena SRC, he oe bah ee ee 130
COMM POSTHC EIN MEE ei r lutte) ee bay fein manne pec) mega pao Ce Ma 127

‘SN AEUOUURGTE SBI BEES «cond Ss30v oo ae A CS RR Pe yo ar Na eae 120
Beane= Card fOr Utter wepammee ces <r ah.r ccet neal Ate dh ad Sh Pinta es uae na Te 340
Sediment Lest: Meum meer epee cee. el, la Se anetrengh ol iene! eae d= os 5 PR en 116
Separation, advantages of centrifugal................................... 155
Central eerie hie Renn tamtnenan Li. (8. 02 cL ie ae 154
melassihicavionkon centage mmachinessat 4.) ae neaeeD 158
conditions affecting completeness of........................... 161

effect of speed as compared with diameter on.................. 164.

NBVCMOTRS KONSTAN TACIMINSS Oi CENA. 4 eee ebeee esac + sve ssc sen 81

ATAVUS acre Nek ce aT AP Ro SS uo) eR 35. 149
heapinearmilkefors: i ctrek eee erage e.. .. . > cee eee | 145
histonyacancucevelopment) oles hr etnnns,....- ene! 155
PDROCESSROMCEMUTIEU Salles sachets 4 <1 ccley OR a a. 5. Une ee ER 158
Separators, farm, introduction and development........................... 168
ODIECEONS EO Rite er oto ean Ne ee eT nar Tite SH erty Wea a! 171

POW STROM pa OT et oxy. uate Nath UM ard MM, 9 = Pm ta! ah 174

HEASOMIS HOT THaOVE CMM, 5S ao bac ac ccc casdouncduceddouc: 168
EMCKMEssmOINCrealnine art k ee tn Cee een. ea 172

SepALatOrmclime qCOMpOSitiolNrol: waetnt. acy ree ee Soe oe 165
SeWwAse-WispoOsdlnplanitsments Ol stay) Aira cael.. eeamemeNie. 9.02. , J:".cSaen ue nel. 209, 300
SirallOwapancreamlMecwnzs s2ys./2 eats eee nein... yams 149
Skim CGemilke ap pOreOming sae eee... Ue tt 12:
Standardswlegalwformbutters.s qe enn) Caen... ol eee 317
GalityAPEOCUCUSS i avert MM de cas. os adn DEER 387
SUED CLC AIGY sacha ereeegene ct a fh pain acta Ne tM oo a 238
SAT Lens eli OU LOMUISE were) n = Wr). eS. See en O37
COMMERCIALS esse eles aa cs ooo A ee 227
definition, history, and classification......................... 225, 226
NOC ALT OTS van, Sate cis ob rete ae EME ae ce isi 2k pale ac ah 2 ee 232
lengthvottimestoCanky 0: eee ie ss xe es fe i eee 236
Mulkypow ders 1Or.;.0 2 4. a ee ea 235

SAUTE ote he CRORES ES 3 0. <0 2 0:5 0S Oe ee 226

[DOOR tcc cd Oo eRe DaREERR ROME CSE oS w cic o 6 Gob cee cha OMe ele ae 236
PORE P ATC OMRON ecva nts. Se ESSE ec eee 226, 230

mbdtema ents acm ual wees ns ae eR See ate IE tae I4I
Pabtronswimonthhyas eh ae emwn Mee ee I4I
BOUCRINIZALLON tc Puen eee ae eM hn) ie 203
Bar Clmtest Siva act ee ON MMe sd cic cde s Wut 201
SinealkeccMUtvere saree wel veer Ua MMMM eRe he ie ae 281

Sugar) miley se oe aes eI ee a: si'stsnai cd aosieeey spake AN tala a 18

404 INDEX

PAGE
Table showing effect of temperature on growth of bacteria................ 56, 57
fat and total solids of milk from various breeds.............. 76
Raintsiim milk; eliminating 2). eae eee ae ee ee nee eat 21, 40
SOULCES: OF. ye teehee g he 8 he rete ES. 20
Temperature. churning. te. landas oo. ee Ee o. ae 240
durationyois|;.2. Soa. Suhr ke aeRe ee Aa en: he 245
ellection on bactenialicnonitine inlet an ae 56, 57
for storing buttery fae, wean era ye ney ek 2 Gu Nee er 206
pasteurization........ SUNG Stich neh Stith eu: our HORAN a cr 202
TIONING, co's cok enoaas SEARS Pees ois a Ee ee err 220
SEPAKA HOME: hoe Heme Nak alee el ents he ice, ee oe 145
wash-water.......... Oe sate NR gee les Soo obid 14 + 263
Mests iad ses Uo ee Na Ah OR es 04, 221
(Cl een er een oe, Loker me the een aM AiR ls oo o.q o:aigia.o.o's « 97
Td) OUR EIS) ene chs pis ANS EURO EHO URES LS MARL Su. slice Beye o> 107
loyoiruermannlle gual Sleinam=wenlies 5 Sasson ods ao aasbozaoschooses --- IO
CLEANS jhe enn: Le he Soe fig cee Oe A 99
TM ss 1c ciel cnc wigs bee creek Ut ae Oe 1.0 ae 98
destss Germenta tion: terns, 6.0 22S cuans cheesy eee tS a 5) ee 04
pasteurized: mileee so). buh ae ee ee een 201
Aovall solids via malls, eineytiOn Oi. 5 2s sn ce uc coocnscanaesusacsoss MSs 5 5
‘Tubs and boxes; paratimimesol koe es eee ee an eee a ee 302
Styles Ole. aati oe Ge ae eae crane eae eee ee 204
treatment Olid yin eee ee eek nice eee oe ae 300
Wdder, ‘externalvappearance ofits | 222k a. Se saat ie ee eee ee 30
AMternaliStruGtume- Of. cit. seit eo os ea «ny eA 23
Wreasamermille 2S cco ad tee tates wade eilegies lyst a yee eee ee 22
Utensils cleanin oye cepees ss: | 2 che tns ahora see Gee Reese 125, 106
Waniation of fat, im) Cream) CAUSES Ofer ).5) eee nee ee ela 8r
amount of water or skim milk used to flush the bowl | 90
GREAT SCE Waa CUS CIC Teta eee 82
rate-ol inflow.4% c4usee ceon 2 suk ee eee 85
michness of milky eoheke ee ee ee 83
speed of machine! yee he. oh eee 87
temperature of uatlkes ee ee 88
Wevaey ioral Gri sizye maviamillke, CAUSE OM GBs wecscccsnconodoouccardoscsceescosae 74
Advance un lactatione 54 ae aeaneeene 78

ACCTOLICOW:.. see ear Oe On ot ee eee 7
breed" ot .cows . :.!/Su-2eL a. abienn we ee oe ee 75
condition of cow... Seb cae el eee eee 80
ENviTOnMeNt..) .'5 ene ee See eae 2 Oe eee 80
feed Or COWS). al ue baht ean oe eee 40
fore and altermill..4 lee een ee eee 77
mavebhwavolveM Ny, On COMSos 14 ccceucsdoarsguarccce! ete 27
anenanavere Ot anil days a gao see seeds Akasa seco uoos 76

time! between mill kines sane eel ei eee ene 75

INDEX 405

PAGE

WAST OS EIMMUSE RO Li ie) is": toma a eboney tain tans Nee eC eA Le culo gi a, anti ons Ba ate 390
ASCO sitar lanl 9% 3). end SR Sr enter AAU wn Aa OR a ag oe te (ah dns imi Mua 37, 39
PESEOLALIONMOIN eet ON ee IM are awe Nir, BC omea taal eh 39

WALLET ANTES <'5..9 4 ob Sto Oe RRR ME ERE REG Lael eae cy ec sat oat ated ate an ea 47
Wollei RS ieay iS ic. ey SA Gs We ea er eNom ree RN Sa a Ve Re Le Mea bi ES
Washing butter, kimdvoh wash=water for... .....0.5..-.+- 90.05 se es neesee- 265
TORING OO SC MONEE tare oN 3 She a eee eM roe es eae 263

AV V/cts ny (CAT) Sarat eee TS SeagraErcor tc amend TUN Aaa AEN le ichs al O 125
VW) RSLS HOW OLRGsie, (COCO! Ce Amen econo oobosn oe ees deb ket oor c 257
GOTMETOIO Ler sees ot ee aeatie ta cereturalcsetcladie iets apelere an ayret eUUsoR pba ta gages 312

WWietteranill (ration er aa eer iewemnt nla yooh de OM UR eet at LD nee Moe ses BO
ingrelvtion tossaltamabuttensey ee eae lst ae, seen een 275
MeshadstOh pUTIyANS Mea Pewee cusyeie Ris jets cna) Aen nares 266
HIS ONO) Meesneste 5 Hiciitedn aloes wesiang 4 Wino! do ahs See RES ecto cis ala) Goals 266
WVSConSiMyGumalatest: oh. l hh see ear RL UAMae Re ew ALAL OL. chic one eas ee 95
Workingsotibultter, dorstorages. eis ae ce ede ie oeieis esc kee lee ee eee: 360

CIOVSCIS AinGl SACS Of og ococccowsomobestoouuucdcovopac 201

ow

sp

* bela ate

*
Atk al

a ii

0000885953