| DAIRY LABORATORY | | MANUAL AND NOTE BOOK | | ERNEST L.ANTHONY, B.S.A. | i” 7 t avi no # i 1 D : : i, i. U . I : 1 1 1 ' a bel I oF Pan ‘ ( 5 % A) t rn " z é i}! . \ f \ ES i =? , . 7 ° . 4 i - : + : : ‘ i : ; ‘ j i ; 7 = Ff A) . ae aa ie : } } , , rf : ~ i ’ i} iv aa / f ' iI) x 7 ~~ — : n — all : a ; _—> ry " ’ + : 7 a . : j - 1 { 7 i ve ; a 7 - ; Ve ou i! 7 ae oe _ A i 7 erik. yan ay in Ost A in Sy Alia bi iy Wier | 7 a ton DAIRY LABORATORY MANUAL AND NOTE BOOK EIPPINCOTTS FARM MANUALS Edited by K. C. DAVIS, Ph.D. ANIMAL HUSBANDRY SERIES PRODUCTIVE SWINE HUSBANDRY By G. E. DAY, B.S.A. Ontario Agricultural College $1.50 net PRODUCTIVE POULTRY HUSBANDRY By Ee RAL EWiuIS SBS. Rutgers College, N. J. = $2.00 net PRODUCTIVE HORSE HUSBANDRY By C. W. GAY, D.V.M.,.B.S.A. University of Pennsylvania $1.50 net PRODUCTIVE SEEEP HUSBANDRY By W.iG. COFFEY, Mis: University of Illinois In PREPARATION PRODUCTIVE FEEDING OF FARM ANIMALS 3y F. W. WOLL, Pu.D. Professor of Animal Nutrition, University of California In PREPARATION COMMON DISEASES OF FARM ANIMALS By R. A. CRAIG, D.V.M. Purdue University In PREPARATION DAIRY LABORATORY MANUAL AND NOTE BOOK COMPILED BY ERNEST ES ANTHONY, -b:5-A. INSTRUCTOR IN DAIRY HUSBANDRY, THE PENNSYLVANIA STATE COLLEGE 15 ILLUSTRATIONS IN THE TEXT PHILADELPHIA AND LONDON Bee eee Ne Osi e. ON PPAUN Gy: COPYRIGHT, I9I4, BY J. B. LIPPINCOTT COMPANY x ta cee ¢ ry Electrotyped and Printed by ike B. Lippincott Company At the Washington Square Press, Philadelphia, U.S. A. B Eo Gcias69g7ss3 “A, APR 21 1914 > Ss ign ek hae VU PREFACE The following exercises have been arranged especially for general courses in the Elements of Dairying. A number of these exercises have been used in separate form and have been brought together for courses of this nature. They are designed to cover the use of the Babcock Tester, Lactometer, and special work with Farm Separators and Churns. They have all been used by the writer in class work, a number of them were recommended by the Com- mittee on the Courses of Study of the Official Dairy Instructors’ Association, These exercises are designed to be used with courses having two or more hours’ laboratory practice each week, and should familiarize the student sufficiently with the general practice so that he may be able to handle the more advanced courses in testing and creamery work. The exercises are on separate pages so that the book may be used as a note book, and all answers and notations can be made while the student is in the laboratory. ERNEsT L. ANTHONY Pennsylvania State College, January 1, 1914 COU ee ce! ae a > Ae oy a 1 aeaty CONTENTS PAGE IE) ENE ONS cee einen eee ea yt Se teas 2 MEY Phe afta, ey Mia RS ose ore reet a Ro SRN 10 BAUR ish LENS, Gass Sar tttaet aa meme mee es Ro Scemanane & seieaer shia: Sta oe COn eer oes. Buas'sl4 chet Series 8 aka, Sree 11 FEV ESutOW > VAIN GACT repentant) ieee ae a al ap a eG enim te eg ee eee ee) doe Remetens i 11 Exercise 1.—Object: To Determine the Physical Differences between Milk, Cream and Skimmilk....... Exercise 2.—Object: To Determine the Accuracy of the Calibration of the Glassware Riser 10m dhe: AW COGKG meni st 2 hatig a eee et Ae a as he eee pg we acta Dee ae EXxercIsE 3.—Object: To Determine the Accuracy of the Calibration of the Glassware Used for the Babcock Test by the Trowbridge Plug Method; also a Method for Wiashinoy up Glassware. pics sesso ace -ish-e tacas i BRIS Dccestgees oe weber = ede cyepse toes 18 EXERCISE 4.—Object: To Make a Test of Milk for Butterfat by the Babcock Method. 20 EXxercIsE 5.—Object: To Test Whole Milk for Fat Content by Babcock Method.... 22 EXERCISE 6.—Object: To Test Cream for Fat Content by Babcock Method......... 23 EXERCISE 7.—Object: To Test Cream for Fat Content by Babcock Method... ..... 24 ExercisE 8.—Object: To Determine the Percentage of Fat in Skimmilk and Whey... 25 EXERCISE 9.—Object: To Determine the Percentage of Fat in Buttermilk........... 26 EXERCISE 10.—Object: To Determine the Specific Gravity of Milk................-. at EXERCISE 11.—Object: To Determine the Total Solids and the Solids not Fat in Milk. . 29 EXERCISE 12.—Object: To Determine the Specific Gravity and Adulteration of Milk... 30 Exercise 13.—Object: To Determine the Effect of not Mixing a Sample Previous to ol Ls) 11 ae eter Me Rea rere Ne Oe ee rare ees © ats a Pee eee eee 32 Exercise 14.—Object: To Determine Effect cf Temperature when Reading the Fat SMES tie ey Ai at a Nicirhastn steer ace ha nus einen od Aseria) circle WetepeL eee onic oh nee Nene pase ahueme Natta Neyan ens 33 Exercise 15.—Object: To Determine the Effect of Speed of the Tester upon the Test.. 34 ExErRcISsE 16.—Object: To Determine the Effect of Varying Amounts of Acid in the RIGOR LOS Dime a els ccae eek cision nang hate ee OE EXERCISE 17.—Object: To Determine the Effect of Temperature of Milk and Incom- Plena Mirxmo on Acid amd Miles sci. wise t owas Head crtlel at, 2d Ses Maney ee ee EXERCISE 18.—Object: To Determine the Effect of Measuring Cream as Compared ERP MVC] RII OR ret c. sce Hee ae , ate oA nee etcetera ge aveRvers ai ev eneeets ar a cllyaes cue ae EXERCISE 19.—Object: To Determine the Effect of Adding Water before Whirling ivehe sprain Creamy Vestas anti eeatams ae a at eita petuterats aie oeislaletareie o\eavean cit bers 38 Exercise 20.—Object: To Test Butter for Percentage of Fat..................005.. 36 39 CONTENTS—ContTINUED EXERCISE 21.—Obdject: To Note the Acidity of Milk Products, and to Compare the Method ‘of Determining the Acidity seme ee tests to Sat ele ete te ea ernel 40 EXERcISE 22.—Object: To Standardize Milk and Cream.................2--eeeeeee 42 EXERcise 23.—Object: To Prepare a‘Commercial Starter..........2......2.2-.+.2. 43 Exercise 24.—Object: To Learn the Correct Use of Milk Coolers................... 44 EXERCISE 25.—Object: To Make a Comparative Study of Cream Separators......... 45 EXERCISE 26.—Object: Comparative Study of Separators. ................. 00. seas 46 EXeERcIsE 27.—Object: To Determine the Capacity of Separators................... 47 EXERCISE 28.—Object: To Adjust Height of Bow! and Position of Cream Screw...... 48 Exercise 29.—Object: To Determine the Effect of Speed Variations on the Proportion of Cream, Richness of Cream, and on the Loss of Fat in Skimmilk.............. 49 Exercise 30.—Object: To Determine the Influence of the Change of Inflow on the Proportion and Richness of Cream, and the Loss of Fat in the Skimmilk......... 50 EXERCISE 31.—Object: To Determine the Effect of Variations in Temperature of Milk and Proportion and Richness of Cream and Loss of Fat................... cera Exercise 32.—Object: To Churn Butter from Ripened Cream. (First Churning Ex- ET.CISC) No Peete a) Sie Nee Aan nae sl Pe HORA Pe ee ee 52 Exercise 33.—Object: To Churn and Make a Good Grade of Butter from Well Ripened Cream: (Second: @hurninoslxercise) is. aace ence ei iene ene orange eee 54 EXERCISE 34.—Object: To See the Effect of Churning at a High Churning Temperature and ‘Washing: ata bow. hemperaturel. fe ances ara caps enter gsc cts heres eee 55 EXERCISE 35.—Object To See the Effects of a Low Churning Temperature and a High Washing Tempera tree nc ays creates jeo er asa es iat cue Buena ele hace erg ee ee 56 EXERCISE 36.—Object: To Determine the Effect of Churning very Thick Cream...... 57 EXERCISE 37.—Object: To See the Effects of Over-working Butter.................. 58 EXERCISE 38.—Object: To Note the Effect of Over-churning on the Quality of the But- Ger Prodivced yy i50 oie ee eR Tee OSES fhe aie Pe ear ree 60 EXERCISE 39.—Object: The Effect of Churning Cream at Different Stages of Ripening 62 EXERCISE? 40:— Objects: Mhetscorinavol Buiterme eae ler eit eee eee aes 64 EXxeERcIsE 41.—Object: To Determine the Percentage of Water in Butter............. 65 DATRY/ ARITHMETIC PROBLEMS=re sae Ce eee tir eer (Al ILLUSTRATIONS \Waswoueton a haere BYoNCMeIon Goce o4 gee Re en oe Ee ae Osuraneen en ocd Smt RIPE REE OR Vint Ke (1 7AGEC Cs) reer iat. gaaed septs eet Set ese en eran iROWEBRIDGE -PLUGSAND (METHOD OF UWSINGs.) foc toes as ale acre cere CORRECT POSITION FOR EmnmInG BORDERS. . asc case ace Correct MANNER OF TAKING READING WITH CALIPERS........... IGHTI-BOTTLE HIANDMDESTER: WARM -SIZH o. 5.0.0 0:.05-6 055-000 Correct Metuop or TakING READING ON WHOLE MILK Bort tes. TREME LOWER MENISCUS TO THE Top OF THE UPPER MENISCUS SMART eAR ORATOR: CREAMAS@AUMSt a. nce auc Se ieries Ack ate mer SMALE OUR=B OPTED SMR eps. badly o .its ei teats ces sos actus taneu es iene cea = SHUM aN OU BYO UNTO ey mn ae ced ee oe ere ne ae irre Soo eal rile la pee TEA CIOME TE RY gant att tie shut tA aia nctesas ae Apes onsets oa apea ceenabe, ecaraeetce fezais [FAG TONE TER: Cavs DN Rees ri ae eis ey ed pene Oa er ees reteg te APPARATUS RORT AGED je MEG ewan sey ie eae eens ecag ers mene aetauene cece We fs HARRENGTONS AGID LESEVAPPARATUS#s cciceia tenes ane escioes seer SPRING BALANCE POR -WHIGHINGHVETER 2 © 4 caste Grehc cis eis @ oo sn ercue FRoM THE Ex- DEFINITIONS Definition for Milk.—Normal milk is a liquid secreted by all healthy females of the mammalian group, for feeding their offspring. Definition for Specific Gravity.—The specific gravity of a substance is the relation between the weight of that substance and the weight of an equal vol- ume of distilled water. Water is always considered as one, or the unit, with which liquids and solids of the same temperature are compared. Examples: 1 gallon of water weighs 8.3 Ibs. Specific Gravity 1. 1 gallon of milk weighs 8.6 Ibs. ne 1.032 1 gallon of butterfat weighs 7.7 Ibs. “ “ .93 Definition of Centrifugal Force.—Ceutrifugal force is the outward pull or pressure brought on a wheel or object when rotating and being whirled from the centre. The centrifugal force is increased (a) directly in proportion to the decrease in the diameter (the velocity remaining the same), and (6) directly with the square of the velocity (diameter being constant). 10 DAIRY LABORATORY MANUAL AND NOTE BOOK DAIRY RULES. 1. Rule for determining the number of pounds of butterfat in a given amount of cream or milk when the percentage of fat is given. Multiply the percentage of butterfat by the pounds of milk and divide by 100 (7.e., point off two places). 2. Rule for determining the percentage of casein in milk when the per- centage of fat is known. (Van Slyke.) Subtract 3 from the percentage of fat in milk, multiply the remainder by .4 and add 2.1 to the result. Milk with 4.8 per cent fat has 2.82 per cent casein [(4.8—3) x.44+2.1= 2.82]. 3. Rule for determining the price per pound received for butterfat in cream when the percentage of fat and the price per gallon are given. Multiply the pounds of cream in a gallon by the percentage of fat given (point off two places). This will give the pounds of fat one gallon of cream contains. Divide the number representing the price per gallon of cream by the number of pounds of butterfat, the quotient will equal the price per pound of butterfat. 4. Rule for determining the price of a gallon of cream when it is being paid for on the butterfat basis. Multiply the percentage of fat in the cream by the pounds of cream in a gallon (point off two places). This will give the number of pounds of fat ina gallon. Multiply this by the price per pound paid for fat. 5. Rules for finding the percentage of solids not fat. Rule A.—(A rough practical rule.) The (Quevenne) lactometer reading plus the percentage of fat divided by 4 equals the solids not fat. Rule B.—(Accurate rule, recommended for accurate work.) One fourth of the (Quevenne) lactometer reading plus .2 times the fat equals the solids not fat. * If the lactometer reading is 31 and the fat is 3.8 per cent the solids not fat equal 8.51 per cent. (81+4+.2X3.8=8.51.) (12) DAIRY RULES (Continvep) 6. Rule for finding the percentage of acid by Mann’s acid test. Multiply the number of ec. of alkali solution used, by .009 and divide the product by the number of cc. of the sample tested, the quotient when multiplied by 100 will give the percentage. 7. Rule for finding the percentage of overrun in butter. Subtract from the butter made, the pounds of fat in the cream used. Divide the result by the butterfat in the cream and multiply by 100. This equals the percentage of actual overrun. If 450 pounds of butter is made from cream containing 395 pounds of fat, the pounds of overrun is (450—400=50). The percentage is [(50 +400) X 100 =] 12.5 per cent. 8. To find the correct specific gravity of a sample when the temperature is other than 60° F. Add one-tenth of a per cent to the reading for each degree above 60°, and subtract one-tenth for each degree below 60°. RULES FOR STANDARDIZATION. In many cases it is necessary to change the per cent fat in milk or cream to some other known per cent fat. This is called standardizing. In much standardization work it is necessary to find the relative amount of two different milks or creams of different percentages of fat to make a certain amount of standardized milk or cream of a known per cent of fat. This is found by: 9. Subtracting the difference between the fat desired in the standard- ized milk, and the milk of the lower fat content; and by subtracting the difference between the percentage of fat in the milk of the lower fat content and the percentage of fat in the milk or cream of the higher fat content. The first result when divided into the last will give the percentage of the amount wanted which must be used of the milk or cream of the higher fat content. This amount taken from the total amount wanted will give the amount of the lower milk or cream to be used, as: 100 pounds of 3.5 per cent milk is desired. It is to be made from milk testing 3 per cent and milk testing 5 per cent. 3.5—3 = .56; 5—-3=2. .6+2= .25. 25 per cent, or 1/4 of the mixture, must be of the 5 per cent milk and 75 per cent of it must be of the 3 per cent milk. 100—25 = 75 pounds of the 3 per cent milk to be used; 25 pounds of the 5 per cent milk to be used. DAIRY RULES (Continvep) (13) 10. The parallelogram method of standardization was devised by Pro- fessor R. A. Pearson, and is illustrated as follows: B D A C 1 In the rectangle let A always represent the percentage of fat wanted in the standardized milk. Let B represent the per cent of fat in the milk or cream of the higher fat content. Let C represent the per cent of fat in the milk or cream of the lower fat content. The proportion D is secured by subtracting C from A; and the proportion E is secured by subtracting A from B. D represents the proportion of B to be taken, and E represents the proportion of C to be taken. These proportions give the parts of the milk or cream of the different percentages of fat which when added together in these proportions will give the desired percentage of fat in the standardized milk or cream. These pro- portions when added together and divided into the amount desired will give in pounds the value of each part. This multiplied by the number of parts found in each proportion will give the number of pounds of each to use. To illustrate: B=22 D=1=parts of 22%. A=4 C=3 E = 18 =parts of 3% 95 pounds of 4 per cent milk is desired. It is to be made from milk testing 3 per cent and cream testing 22 per cent. 18+1= 19 parts. 95+19=5. 5 represents the value in pounds of one part or proportion. Then 5 x18 =90 pounds of 3 per cent to use. 5 <1 = 5 pounds of 22 per cent to use. 11. Where milk is to be reduced by adding skimmilk. By dividing the percentage of fat in the milk wanted by the percentage of fat in the milk on hand will give the percentage or the amount of the milk to be used, and the rest must be added as skimmilk. Thus: 300 pounds of 5 per cent milk is to be mixed with skimmilk to form 4 per cent milk. (4+5 = .80.) Then 300 pounds represents 80 per cent of. the (14) DAIRY RULES (ContInvEpD) mixture wanted, and the rest, or 20 per cent, equals the amount that must be added as skimmilk. 20 per cent of 300 = 75. 300+75 = 375 pounds of the standardized milk. 12. Where milk is to be raised to a higher per cent of fat by adding milk or cream of a still higher fat content. Subtract the percentage of fat in the milk on hand which contains the lower fat content from the percentage desired in the standardized product. Take the difference between the percentage of fat in the milk or cream of the higher fat content and the desired percentage of fat in the standardized milk. Divide the first result by the second, and the result represents the part of the milk or cream of the higher per cent fat to be used. Multiply this result by the pounds of milk which contains the lower per cent fat, and this will give the amount of the richer milk to add. This, added to the amount of the milk with the lower fat content, will give the total amount standardized. Thus: 300 pounds of 3 per cent milk is to be made to test 3.5 per cent by adding 5 per cent milk. (3.5 per cent—3 per cent = .5; and 5 per cent—3.5 per cent = 1.5); .5+1.5 = .33 1/3; 300 x.33 1/3 = 100. Use 100 pounds of 5 per cent milk with 300 pounds of 3 per cent milk, or a total of 400 pounds of 3.5 per cent standardized milk. 13. By dividing the per cent of fat in the standardized milk into the percentage of fat in the milk on hand and multiplying the result by the num- ber of pounds of the milk on hand will give the number of pounds of the standardized milk which can be made from the milk on hand. If the quantity of the standardized milk is less than the amount on hand, then the difference must be taken out as skimmilk; if greater, it must be added as skimmilk. To illustrate: 300 pounds of 3.5 milk will make how many pounds of 4 per cent milk? 3.4+4 = .875; .875 x300 = 262.5 pounds of 4 per cent milk which can be secured, or 300—262.5 = 37.5 pounds of skimmilk to be removed. 14. When it is desired to determine the number of pounds of standard- ized milk a quantity of milk of a lesser per cent of fat will make. Find the pounds of butterfat in the quantity of milk by multiplying the pounds of milk by the per cent (point fat off two places).. Then by dividing this result by the percentage fat desired in the standardized milk and multiplying the result by 100 will give the number of pounds of stand- ardized milk. Thus: 300 pounds of 3.5 milk contains (300 <3.5 = 10.5) pounds fat. This would make (10.5+4 x100 = 262.5) pounds of milk testing 4 per cent. TENGE eeere ie er nk se Gm att a : EXERCISE 1. (15) OssEcTt.—To determine the physical differences between milk, cream and skimmilk. APPARATUS.—Samples of milk, cream, and skimmilk, beakers, and micro- scopes. Note to Instrucrors.—Slides of skimmilk, whole milk, and cream should be prepared previous to the class period, and adjusted in, the microscope, as students in first taking up this work will not be familiar enough with the different apparatus to properly make up the slides. Step 1. Study the differences found in the appearance of the sample of the ‘milk, cream, and skimmilk. Step 2. Study the field under the first microscope. Note the size, the shape, and the color of the fat globules. Step 3. Study the field under the second microscope. Note the number of fat globules compared with those in the field of the first microscope. Note their size and shape. Step 4. Study the field under the third microscope. Note the size and shape of the globules compared with those of the second microscope. Step 5. Draw one of the fields in the space of this page. Write up the steps at the bottom of this page, explaining all the differences noted in the three fields. (16) g S R| ~ TOY ON TY TC Oo oo Jue SAO BMS to PA Bre GW BG EVQKGV SSSS SS Es ~ S Seq Whole milk bottle. OS SS ~~ “Ss ~ x = SNS SSAA, GS aa C2 AN SANS ANS Ss 17.6 ce. pipette for milk. EXERCISE 2. Opsect.—To determine the accuracy of the calibration of the glassware used for the Babcock test. APPARATUS.—Set of bottles used for test, and burette. Sheet of filter paper. Step 1. Burette Method.—Fill the bottle to be tested to the zero mark with water. By means of a strip of filter paper remove any water adhering inside the neck above the zero mark. Measure into the bottle, from an accurate burette, 1 cc. of water. If the bottle is correct this should bring the water to the 5 per cent mark. Another ec. from the burette should bring the water to the 10 per cent mark. In ease of the cream bottles, if 9 gram bottles are used, 1 ce. of water will fill the bottle to the 10 per cent mark, or 5 ee. to 50 per cent mark. Test all bottles by this method, re- cording all data. Step 2. Accuracy of the Pipette—Allow 17.6 ce. of water from the burette to run into a pipette, the bottom of which is closed with the finger. If correct the water will be at the 17.6 ec. mark. Any glassware showing more than .2 per cent error should not be used. EXERCISE 2 (ContTINvED) Data. Style of bottle Bottle No. Water by measure Variation 5% mark Total variation Pipette (18) EXERCISE 3. Oxssect.—To determine the accuracy of the cali- bration of the glassware used for the Babcock test by the Trowbridge plug method; also a method for washing up glassware. APPARATUS.—Set of bottles used for the test, set of Trowbridge (or Nefus) plugs, sheet filter paper. Part 1. Trowbridge Method.—Fill the bottle to the zero. With filter paper, dry the neck inside above the zero mark. Insert the plug until the water rises half way between the two sec- tions. In a correct bottle the surface will be at 5 per cent. Lower the plug until the upper portion is 1/8 inch below the surface. The water should be at the 10 per cent mark. Record all data. Part 2. All glassware should be thoroughly washed and be always left clean at the end of each laboratory period. Take a dish pan of warm water and put in it about two tablespoonfuls of some good washing powder. Put the bot- tles in the suds thus formed and let the bottles fill about half full of the hot solution. Then take bottles in each hand and shake well. After they have been washed as well as pos- Bde Sete sible in this manner use a small bottle brush to clean out the necks of the bottles. Take them out of the water and rinse with clean warm water. Use this same method for all, other glassware. This method if carefully used will always keep all glassware in the best possible condition. Care and attention should be given to always have all apparatus in the best possible shape. EXERCISE 3 (ContTInveEpD) Data. (19) Style of bottle Bottle No. Variation 5% mark Total variation (20) EXERCISE 4. Opsecr.—To make a test of milk for butterfat, by the Babcock method. ApparatTus.—Iwo whole milk bottles; a 17.5 cc. pipette; acid measure; acid; sample of whole milk; two sample bottles; hot water bath. Step 1. Practice using the pipette with water until you can reasonably adjust the amount to be taken; Liorce: Correct manner of taking reading with calipers. Correct position for filling bottles. Step 2. Always have milk between 60° and 70° F. before drawing sample with pipette. Step 3. Mix the milk thoroughly by pouring from one vessel into another before drawing sample. Always pour down the side of the vessel. Step 4. Put 17.6 ec. of milk into each of two whole milk bottles. Allow the milk to run down along the neck by holding the pipette and bottle at an angle of about 60°. (Letter one sample ‘‘A”’ and the other ‘‘B”’.) Step 5. To each bottle add 17.5 cc. of sulphuric acid (1.82 to 1.83 s. g.), using an acid measure. Turn bottle slowly as acid is added, allowing acid to run down the sides of the neck. EXERCISE 4 (ContTINvUED) (21) Step 6. Agitate each bottle until the curd is all dissolved, by giving it a rotary motion as soon as acid is added. Step 7. Put them into a centrifugal machine, whirl five minutes, fill to the neck with water about 130° F., whirl two minutes, fill to about the 9 per cent mark, whirl one minute, and read. Norre.—Read the whole milk test from the top of the upper meniscus to the bottom of the lower meniscus. Report. a : ‘ BottlesINOnou 3.8 eee A | B Cathe os Kaen hee | 1. Below give reasons for having the milk at 60° to 70°. 2. Why is the milk poured from one vessel to another before sampling? 3. Explain the ac- tion of acid in the test. 4 Why should each sample of milk be tested in duplicate? 5. What is the color of the fat column? Pan } ] th | | | | Hi Hight-bottle hand tester. Farm size. Correct method of taking reading on whole milk bottles. From the extreme lower meniscus to the top of the upper meniscus. (22) EXERCISE 5. Onsect.—To test whole milk for fat content by Babcock method. Repeat Exercise 4. Test as many samples of milk as possible during the laboratory period. 1. Try to account for any difference in tests between samples “A” and ““B” in each case. 2. What would be the pounds of butterfat given by a cow giving 8000 pounds of milk per year with the fat test of your first sample? 3. What would be its total value at 38 cents a pound? 4. Why is 17.6 cc. of milk used for the test? 5. Why are the bottles set in water at 130° F. before reading? EXERCISE 6. (23) OxssEecT.—To test cream for fat content by Babcock method. APpPARATUS.—Two cream bottles; acid measure; acid; 17.6 ec. pipette; sample of cream; two mixing beakers; scales; hot water bath. Step 1. Mix sample of cream thor- oughly by pouring from one beaker to another, care being taken not to churn it. Step 2. Balance cream bottle A on seales and weigh into it 9 grams of cream. Duplicate in bottle B. Step 3. Measure out about 9 cc. of water at 60° to 70° for each cream bottle. Add to each bottle. BP Step 4. Measure out 17.6 cc. of acid == Ve for each bottle and complete test Srvall laborabarnoreamecnles, as for whole milk. Note.—Read cream test from bottom of fat column to bottom of top meniscus. Report. At the bottom of the page explain— 1. Why cream columns are different from milk. 2. Why cream is weighed out instead of being measured out, as is done with milk. 3. Why 9 ce. of water is added before the acid. (24) EXERCISE 7. OxssecT.—To test cream for fat content by Babcock method. Repeat Exercise 6. Run as many samples as possible, during laboratory period. Report. At the bottom of the page ex- plain— 1. How many pounds of fat in 1875 pounds of cream with a test of the first sample? 2. What was the color of the fat in the column? Any variation? 3. What would happen if the acid were added before the water? Mm | AN Small four-bottle tester. EXERCISE 8. (25) OpsecT.—To determine the percentage of fat in skimmilk and whey. APPARATUS.—Samples of each, skimmilk and whey; skimmilk bottles; pipette; acid measure; mixing beakers; acid; hot water bath. Step 1. Measure out 17.6 ec. first of skimmilk in each of two skimmilk botiles. Proceed as for whole milk test except use a little in excess of 17.5 ce.of acid: Step 2. Repeat test in the same manner using whey instead of skimmilk. SSS SSS SSS Skimmilk Bottle. Report. Skimmuilk bottle No... : | | | A % of fat ; 5 Peart: | Whey bottle No......| | | ( A | CHEM ato ee pon ee 7 i B | | At the bottom of the page explain— 1. Why is a different bottle used for whole milk than skimmilk? 2. Why is a little more acid used than in the whole milk test? 3. How many pounds of fat in 1700 pounds of skimmilk with the above test? In 2500 pounds of whey with the above test? 4. Give length of time for both tests. (26) EXERCISE 9. Oxssect.—To determine the percentage of fat in buttermilk. AppaARATUS.—Sample of buttermilk; two skimmilk bottles; two whole milk bottles; pipette; acid measure; mixing beakers, and acid. Step 1. Measure out first 17.6 cc. of buttermilk im each of the skimmilk bottles; also make up duplicate tests of buttermilk in whole milk bottles, as buttermilk may be too high in fat content for skimmilk bottles. Step 2. Complete the tests as before. Read the test which is the most accurately measured. Report. Buttermilk in skim- | | | | | | | | | milk bottle No.. . .| | | | | | | | Buttermilk in whole milk bottle No... . { A | | % of fat eee | ca 7/0 " B | | | | | | At the bottom of the page explain— 1. Why are two sets of bottles used for the buttermilk test? 2. Why is a little more acid used than with the whole milk test? 3. How many pounds of fat in 1700 pounds of buttermilk with the above test? (Show operation.) Grade 1 1) (5) o's aU cee a ee ee EXERCISE 10. (27) OxssEcT.—To determine the specific gravity of milk. AppaRATus.—Lactometer; lactometer cylinder; thermometer, and sample of milk. Step 1. Thoroughly mix sample of milk and regulate temperature between 60° and 70° F. Step 2. Fill cylinder nearly full of sample of milk. Place lactometer in sample and observe exact reading on lactometer after it has become still. Caution.—Care is necessary to not let the lactometer drop in the _ eylinder, as the lactometer is very easily broken. Step 3. Record exact temperature of sample and lactometer reading. Step 4. Test sample by Babcock method for fat content. SRS NO URNS Ss ‘ y d f d SSN ere Ga aT east | IrASASN =~ «OEE AE Se A fos Lactometer. Lactometer cylinder. (28) EXERCISE 10 (ContinveEp) Report. | Reading corrected for | ? Sample No. | Temperature, J.actometer reading temperature % fat 1. Calculate the solids not fat and the total solids from the above data. (For figuring total solids and solids not fat see rules 6, A and B.) 2. What are solids not fat? 3. What is the specific gravity of normal cows’ milk? 4. Why is it necessary to make the correction in the lactometer when the temperature is other than 60°? 5. When milk is heated, what is the effect on its specific gravity? 6. How does cooling milk affect the specific gravity? EXERCISE 11. (29) Oxssect.—To determine the total solids and the solids not fat in milk. ApparAtus.—Babeock test outfit; lactometer and equipment; a sample of whole milk. Step 1. Regulate temperature of whole milk sample until near 60° F. Pour into cylinder and earefully take lactometer reading. Step 2. Make a Babcock test for fat. Record all data, and by rules 6, A and B figure out the total solids and solids not fat for the sample. Repeat for a second sample. Report. yl Lac. reading een. % fat Deter a : ed for temp. | A 2 B | Solids not fat | Total solids | Sample No. 1........ | | { SN OS a 1. What would be the total solids in a sample having a lactometer reading of 32.6 at 68° F. and a fat test of 3.8 per cent? 2. How many pounds of solids not fat in 400 pounds of this milk? (30) EXERCISE 12. OssEect.—To determine the specific gravity and adulteration of milk. APPARATUS.—Two samples adulterated with water; one normal sample; lactometer and cylinder; thermometer; test outfit; mixing beakers. Step 1. Proceed as in Exercise 11. Step 2. Record data, figure out solids not fat, whether samples are adulter- ated or not. If adulterated, nature and percentage of adulteration. Report. Sample | Temp. | Lact. | Corrected read-| % fat Solids not Adultera- % adultera- No. | reading | ing fat tion tion a ee el a - EXERCISE 12 (Conttnvep) (31) ; 7 1. Calculate the solids not fat in a sample of milk testing 3.6 per cent - fat, with a lactometer reading of 34 at 52° F. 2. What are the solids not fat in a sample of milk testing 2.8 per cent fat, with a lactometer reading of 26 at 60° F.? 3. Is this sample adulterated? 4. If this sample has been adulterated, what has probably been used as an adulterant? 5. What makes you think this? (32) EXERCISE 13 Oxssect.—To determine the effect of not mixing a sample previous to testing. AppaRATUS.—Sample of milk that has stood for an hour or two without being stirred; the Babcock test outfit. Step 1. Without disturbing the sample of milk on the desk, draw two samples from the top. Step 2. Draw two samples from the bottom. Step 3. Mix the milk thoroughly by pouring; take two samples. Step 4. Add proper amount of acid to each, mix and complete the tests. Report. \ Before mixing | = = So After mixing Top | Bottom | A | B A Be A B Bottle No...... | AEC) eee 1. Explain below what would be the losses to a creamery receiving 45,000 pounds of milk daily if the above careless methods were used in test- ing the samples, supposing the sample was taken from the top. 2. What loss to patron if sample is taken from bottom? 3. What would be the percentage of error in the above tests? EXERCISE 14. (33) Ossect.—To determine effect of temperature when reading the fat test. APPARATUS.—Sample of cream; whole milk; skimmilk; Babcock test outfit. Step 1. Measure out two bottles of whole milk, two of skimmilk. Put 9 grams of cream into each of two cream bottles. Step 2. Add proper amounts of acid, mix and complete the tests. Step 3. Take reading as soon as whirling is complete. Step 4. Temper the water bath to 200° F. Insert the bottles so the water comes near the top. After being inserted five minutes, read. Step 5. Lower the water to 150° F., after five minutes read. Step 6. Lower to 130° F. and, after five minutes, read. Step 7. Lower the water to 90° F. and, after five minutes, read. Report. Whole milk Skimmilk Cream A | b Bottle No...... | First reading % 2002 9 fates s.<. OOS OG Tat cic RSOs Sp ifatie. 25.4 OOF OG Talis Sorieas 1. Which is the proper reading and why? 2. What would be the loss to a creamery taking in 30,000 pounds of cream if the test was read, as in step 4, at 200°? 3. What loss to patron if read, as in step 7, at 90°? 4. Give variation in the color of the fat at the different stages. (34) EXERCISE 15. Ossect.—To determine the effect of speed of the tester upon the test. APPARATUS.—Samples of whole milk; skimmilk; Babcock test outfit. Step 1. Prepare three test samples of whole milk. Note.—In this exercise have all conditions alike except speed. Step 2. Prepare three test samples of skimmilk using skimmilk bottles. Step 3. To the skimmilk add a little more than a full measure of acid. Mix as usual. Step 4. Run one bottle of whole milk and one of skimmilk at half speed; one of each at proper speed; one of each at high speed. Report. Whole milk % fat Skimmilk % fat |. ae | | AG ali SpCEd*. ous batts | | At proper speed........ At high speed........... | | At the bottom of the page explain— 1. The effects on the color of the fat. 2. Other effects of insufficient speed. 3. Other effects of too much speed. EXERCISE 16. (35) Oxssect.—To determine the effect of varying amounts of acid in the Babcock test. APPARATUS.—Sample of whole milk; Babcock outfit. Step. 1. To one sample add the regular measure of acid. Step 2. To another add half the regular amount of acid, 8.8 ec. Step 3. To another add 1 1/2 measures of acid, 26.3 ce. Step 4. Mix and test in the usual way. Report. Regular measure Half measure 1 1/2 measure 1. What is the effect of insufficient acid? 2. Of too much acid? 3. Write a full description of clearness, color and correctness. (36) EXERCISE 17. Ossect.—To determine the effect of temperature of milk and incomplete mixing of acid and milk. APppaRrAtTus.—Sample of whole milk; Babcock test outfit. Step 1. Measure out two samples, add acid at once and mix thoroughly (usual method). Step 2. Measure out two samples, place in water bath at 130° for ten min- utes; then add acid and rotate to dissolve curd. Step 3. Measure out two samples, add acid but allow same to stand ten minutes before dissolving curd. Step 4. Complete all tests. Report. Usual method Too hot Stood too long ens Reaeel ey [3h A B iBottleaNow.. .. Cu ateetg: ese. ae Explain below— 1. The effect of having the sample too hot before adding the acid. 2. The effects of allowing the sample to stand with the acid on it before mixing. 3. Give the different colors of fat in the tests above and give reasons for these changes. Grauecwere tee ee a has. cee 1 DEY ite ae ee gets a aa EXERCISE 18. (37) OpsEcT.—To determine the effect of measuring cream as compared with weighing it. ApPARATUS.—Sample of cream; Babcock outfit; 2 9-gram and 4 18-gram cream bottles. Step 1. Measure into each of two 18-gram bottles 17.6 ec. of cream. Step 2. Add 17.5 ce. of acid, rotate well and allow to stand until mixture turns black, then add hot water up to the neck of the bottle. Step 3. Weigh out 18 grams of cream into each of two 18-gram bottles. Add acid and water as in step 2. Step 4. Weigh into each of two 9-gram bottles 9 grams of cream and test in the usual manner. Report. 17.6 ce. cream 18 grams cream | 9 grams cream A B A | B A B Bottle No......| | | 1. Which test should be the correct one? 2. Give the advantages and disadvantages of weighing out cream for a test. 3. With how many pounds of fat would a cream patron be over-credited if he delivered 467 pounds of cream and was allowed the highest test? 4. How much would he be short if paid by the lowest test, butter being worth 30 cents per pound, overrun being 14 per cent? (38) EXERCISE 19. OxssEect.—To determine the effect of adding water before whirling in the 9-gram cream test. APPARATUS.—Sample of cream; Babcock test outfit. Step 1. Weigh into each of two 18-gram bottles 18 grams of cream. Step 2. Weigh into each of two 9-gram bottles 9 grams of cream. Step 3. Add the proper amount of acid to each lot. After standing a few minutes add hot water to one half of each lot. Step 4. Mix and finish the tests. Report. 18 grams | 18 grams | 9 grams | 9 grams no water | with water | no water | with water A ook | ANIL loiee al A 1B je a A B Bottle No. | | les | | Ore 8 Geet | Write a full description of the variations in the above tests with reasons for (a) color, (b) clearness, and (c) correctness of the fat test. EXERCISE 20. (39) Ossect.—To test butter for percentage of fat. APPARATUS.—Sample of butter; Babcock test outfit. Step 1. Preparing sample.—Put a fair sample into a tightly stoppered bottle. Put the bottle into water at 95° F. and shake thoroughly until melted. Then put the bottle into cold water and shake well until butter becomes of a thick, creamy consistency. From this sample small por- tions may be taken for testing. Step 2. Testing—Weigh 9 grams of butter into each of two bottles gradu- ated to 50 per cent, add 10 cc. of hot water, and about 8.5 ce. of acid. ’ Mix until all the curd is dissolved. Add hot water to bring the fat into the neck of the bottle. Whirl in a centrifuge for five minutes and read. The reading multiplied by 2 will be the correct test. Report. le on Bele hi Be rl as A B..) B Bottle: Noe a... Oe: SENG comings Corte 1. If butter contains 80 per cent fat what should be the percentage of overrun? 2. What is the average composition of butter? 3. What is the percentage of butterfat allowed by law? (40) EXERCISE 21. OxssecTt.—To note the acidity of milk products, and to compare the method of determining the acidity. APPARATUS.—Sample of milk; cream; cheese; skimmilk; buttermilk; Far- rington’s, Mann’s and Van Norman’s apparatus; solution for acidity tests. Step 1. Follow the printed directions for the particular test being used. (See rule 6.) SS SS =~: Apparatus for acid test. Farrington’s acid test apparatus. EXERCISE 21 (ContinveEp) (41) Report. Percentage acidity Sample od eehee Farrington's Van Norman's : 1 So Ae 1. 5) 203 mo ae Cream A...... Cream B...... Skimmilk A... | Skimmilk B.... Buttermilk A. . Buttermilk B. . Cheese A...... Cheese Bass. Write the advantages and disadvantages of each test. (42) EXERCISE 22 Ossect.—To standardize milk and cream. APPARATUS.—Sample of milk and cream; Babcock test outfit; sample bottles; cream scales. Step 1. Run test for fat on both cream and milk samples. Step 2. Standardize 100 grams of 4 per cent milk from the tested cream and whole milk samples. Step 38. Standardize 100 grams of 20 per cent cream from the tested whole milk and cream samples. Step 4. Run fat tests on all standardized samples and record data. Report. | Step 2. Grams used Step 3. Grams used zs AS 2B : =| [SAE ae BottlesNomeens oe a Milk Cream | Milk Cream Test of whole milk...: : =. Mest ot Creasm......>....- Test after step 2........ Test after step 3.........| Work out the following problems— 1. One thousand pounds of 3.6 per cent milk is to be raised to 4 per cent milk; how much skimmilk must be taken out? 2. How much 30 per cent cream and skimmilk must be used to make up 1000 pounds of 25 per cent cream? 3. How much 36 per cent cream and 3.6 per cent milk must be used to make up 800 pounds of 25 per cent cream? 4. How many pounds of 40 per cent cream and 4 per cent milk must be used to make up 90 pounds of 20 per cent cream? Da aan, EXERCISE 23. (43) OssEcT.—To prepare a commercial starter. APPARATUS.—A pint bottle, sterilized; a sample of commercial starter; a sterilized graduated cylinder; a sample of pasteurized skimmilk; a thermometer. Step 1. Measure out 25 ee. of the commercial starter into a sterilized pint bottle. Add to it 225 ce. of pasteurized skimmilk at a temperature of 80° F. Step 2. Place cover on bottle and set away in starter box at a temperature of 70° F. for 24 hours. Hold at this temperature until all changes have been noted. Step 3. Record all the changes which a starter undergoes from the time it is made up until observations are complete. 1. Write a full description of a starter and all the changes which take place in its manufacture. 2. Explain as fully as possible the reasons for each change. 3. Give briefly the advantages of using a starter. (44) EXERCISE 24. Oxpsect.—To learn the correct use of milk coolers. APPARATUS.—Quantity of water or milk; milk cooler; supply of milk cans; thermometers. Step 1. Weigh out 100 pounds of the milk or water and have the tempera- ture about that of milk when taken from the barn, 90°. Place in the cooler vat. Step 2. Arrange the cold water inflow to give full flow, take the temperature of inflow, of outflow, and length of time to cool the milk to 50° and the amount of water needed. Record data below. Step 3. Same as step 1 and 2 except have water passing through the cooler with only half pressure. Record data. Step 4. Same as step 1 and 2, only determine the length of time and amount of water necessary to cool to within 3 degrees of the temperature of the water. Take temperature of inflow and outflow in all cases. Report. Temp. Temp. | Temp. Time Amt. water | Temp. when milk inflow | outflow required cooled EXERCISE 25. @ 16, Le. @ SEA) He, 6) Bi ei"e* ON 6) 85a Le) 6. (6, 6) a) a Ogee hgh eae C6 OK a sO er SO) Gi 6) 6 6) Ge 6 C16, wee oes Oxssect.—To make a comparative study of cream separators. APPARATUS.—Separators in separator room. Steps. Record. Study several separators and fill the record columns correctly. . Name of separator bo . Factory number.. . . Size number . Revolutions of bowl per one turn of | PPO DCCOhOls Gran kKwye Aare. sot ees is 4 see » - ae BSD CCONOS DO Weimer minydcan dempamenin 2c VA LEU MCRD ACH Vinisys cats ac sinters « +.) 3 REINO S OlsP Caan ta eatin soviteth. re, ceitaracs slog | INI shin oye na Yee eee Rel aichealOGabedacms can & co sae ces. PT I(Giign 2) ts 90008 01d ee are cea Der WeIrwht OF DOW lss1s 25. acld occas’ ed shee s | PO WLIO Gael ee ate eee ted. < oO 3 . Height of top of receiving tank from . Height of crank spindle from floor.... . . Height of crank handle from floor at. lOWESt DOSITION< . 5a) hy Ne eee ee. pe Minliksenters: DOWle.cs2 c.cu. 2 eee een . Skimmilk leaves bowl... ............ . Which is cream spout?...............] . Pressure of worm gear, down or up?. .. Write a criticism of each machine studied and its disadvantages. give its special advantages radon cate cee Lene Sete ae yee 2 Daten Rey Coen oe (46) EXERCISE 26. OssEecT.—Comparative study of separators. APPARATUS.—Separators In separator room. ProcepurE.—Carefully remove the neck bearing which is located in the upper seating for the bowl. Study the character of the bearing with regard to the points indicated below. When through, carefully replace and adjust the bearings before leaving the machine. Follow the same instructions for the bottom bearing which is located at the lower seat- ing of the spindle. Report. Neck-bearing Bottom-bearing Name of separator Character of spring; crown, spi- Flat or sharp, pin on point, or both, or balls? Is it a weight- carrying or guide-bearing? Ad- justable as to height? ral, wire or ribbon; adjustable or non-adjustable? At the bottom of the page make criticism as to ease of removing and replacing the bearings, of each of the machines studied. Oxssect.—To determine the capacity of separators. APPARATUS.—Two large dippers; 2 fourteen quart pails; a quan- Step 1. See that the milk is at the right temperature, 90° to bo EXERCISE 27. (47) tity of milk. (Two or more students may work together.) 98° F., and that there is a sufficient amount to maintain a full flow during the experimental run. Start separat- ing, and catch the first cream and skimmilk in dippers. When the milk is running a normal flow, take the dippers away and let the skimmilk and cream run into the regu- lar pails for exactly one minute. Take them away and let the rest of the milk run into the dippers. Weigh up the amount of skimmilk and cream which was caught in the one-minute experimental run. Compute the capacity per hour. Flush bowl with warm rinse water. Save samples of skimmilk and cream. Spring balance for weighing milk. Report. INU naaYSs COE ASS) o HUNTON Oe cey Oe ees en oc N eae eg Oe S12, a oe setae res cate hae enveieyey Some he eee ola eR ak, OO ee apt Rac, Ae Rated capacity per hour..................... ee ee eee Record speed of handle three times ............ 00.0. c cece cece eee e eens eae eee ere Temperature of milk at start;..... fa R EAN carat eis ha A atin th. Gover oauly oe EN et Pounds of skimmilk,............. SESTOONLIE eecpt ae se LO UT aes nc Gendarme nee kee Pounds of cream,................ Ba aatnay, ome. -omeag Nl ne) 9 1 Pane ee ee kek eee Pounds Gekimmilkaand cream, 2; timings ..52..1 OUri 2) x. cGauke dean tss a2 ke Below show how long it would take each day to separate the milk from thirty cows, each giving 35 pounds daily, with a machine of a capacity of the above machines. (48) EXERCISE 28. Oxssect.—To adjust height of bowl and position of cream screw. APPARATUS.—Separators in separator room; quantity of whole milk. Step 1. Name of separator. Step 2. See that height of bowl is such as to deliver skimmilk and cream into their respective covers without touching them. Before making any adjustment, study direction sheet for this machine thoroughly. Step 3. With sufficient milk (or water) in supply can to maintain full flow, separate at least one gallon, shut off supply, weigh and compute what proportion the cream is of the total amount separated. Step 4. Adjust cream screw to make the amount of cream between 12 and 14 per cent of the total separated. Step 5. If already correct, adjust so as to make a change of between 4 and 6 per cent. Report. Ist trial 2nd trial | 3rd trial Skammilike MOUNGS© ona satan stiles seine Grea ;POUNGS We neuer eee Gate ENO Ua sO OUT Seer ane ee eee ee tes ore eae | | % of total taken as cream............ | | Explain below— 1. How much change was made in the cream screw? 2. How does the cream screw affect the amount of cream? 3. How does it affect the amount of fat? 4. When water is separated, would the amount of water leaving the cream spout be the same as the amount of cream when milk is separated? 5. Give reason for your answer. EXERCISE 29. (49) Ossect.—To determine the effect of speed variations on the proportion of cream, richness of cream, and on the loss of fat im skimmilk. APPARATUS.—Separators in separator room; quantity of whole milk. Step 1. Have milk at 90° to 98° F. Step 2. Separate half the milk at regular speed. Step 3. Separate remaining half with speed reduced one-third. Step 4. Save sample of whole milk; also samples of cream and skimmilk from both two and three. Report. Natn GraoftceDALAtOLimaiarssiela's clea lets teloiclesiclelere jotelsis) crore) cles aieiersieive sye'sieo se" ¢ SIZG cars aaterohoteteceus a avehentye: siroyere: ievencees | First trial Second trial (nae a | 1st half | 2nd half Ist half 2nd half Pounds of milk used ...... Peis Temperature of milk.......... | | Note speed three times ........ Pounds rinse water used... .... Pounds skimmilk Jo2....g..0:. POuUNGS Grease. setae sie fll Pounds skimmilk and cream .. || Proportionsolecream sa: 26.60; Mestror wholewnilk’ 2355.2: 45 .-| MBEStLOMsCr@atii 4 jc See ees Mhesteon skim ones oe | Pounds butterfat in milk ...... Pounds butterfat in skimmilk . . Pounds butterfat in cream... .. Pounds fat unaccounted for... . %, fat unaccounted for ........ Write the reasons and effects of the variations that you have found in this exercise. Date teen te on Mee SM Ay wt G. (50) EXERCISE 30. OxssEecT.—To determine the influence of the change of inflow on the propor- tion and richness of cream, and the loss of fat in the skimmilk. APpPARATUS.—Separators in separator room; quantity of whole milk. Step 1. Separate half the milk with faucet wide open and speed uniform. Step 2. Separate the other half, starting with faucet wide open, then close till cream becomes noticeably thicker: Note.—Maintain correct and uniform speed. Save samples and test. Report. INiamexofiseparatonercretiam sieitierc cheis closelevese/elels(elsiersleiststeletomys lereie/ rete ie eiecs eae LZ Olena) skclotanhe ehohcieneVenelepoteiate ieaekensestenete First trial Second trial Ist half 2nd half Ist half 2nd half Pounds of milk used .......... ie | Temperature of milk.......... | Note speed three times........ Pounds rinse water used....... Poundstskimmiulk 5.) eee Poundsicresmee- saree ee Pounds skimmilk and cream .. . = — ;——— = ———— — - : ———n Proportion, of creamy... eee eulhestior whole wii ke os) a seen eee | MeStHOMCEEATN Ae ok sane ere Adee Coun tlabeavectlbler, 4 enn esau 6 b~ Pounds butterfat in milk ...... | | Pounds butterfat in skimmilk . Pounds butterfat in cream... .. Pounds fat unaccounted for... . | oar aad : | % fat unaccounted for ........ | | Write the reasons and effects of the variations that you have found in this exercise. EXERCISE 31. © 0@) (@ (eusi.e © 16 je le wsele. 6) @) ¥/'6)(0..0 9 le © 6 6 0s] e's eete’ el elem elie! eve) tw tmp) 60) 0) 1¢):6).0)'8! 616 066; ©. 816 6 (51) OssEcT.—To determine the effect of variations in temperature of milk and proportion and richness of cream and loss of fat. APPARATUS.—Separator in separator room; quantity of whole milk. Step 1. Separate half the milk at about 90° F. Step 2. Separate half the milk at about 50° F. Notre.—Maintain correct and uniform speed. Report. Save samples and test. Nanri GuOtise pare toni ss stereo vetetel suet: fateierais;twhelenslelerore oheveh icuste clic.) acts! lol's ae fate SIZE ss aavereunetetev ei ones tae Welw tere tame ete e Is First trial Sha |. Pounds of milk used Temperature of milk Note speed three times ........ | Pounds rinse water used | Second trial 2nd half Ist half | 2nd half ; —- Pounds skimmuilk Pounds cream Pounds skimmilk and cream .. . Proportion of cream Mestrotawiho lemme on aseaaa ey see Test of cream Test of skimmilk Pounds butterfat in milk Pounds.butterfat in skimmilk . . Pounds butterfat in cream ..... Pounds fat unaccounted for... . % fat unaccounted for Write the reasons and effects of the variations that you have found in this exercise. (52) EXERCISE 32. Ossect.—To churn butter from ripened cream (first churning exercise). AppaRATuUS.—Churn; cream; scales; thermometer; pails; salt; color; ete. (Two or more students may work together in all churning exercises.) Notre.—Students going into the laboratory should first note the work to be done, which will be found on the slip on the bulletin board or on the blackboard. General Instructions for Churning.—The principle of churning is the proper agitation of the cream that the butterfat which is in it is properly and thoroughly separated out. Before churning, the cream should be properly ripened. That is, it should have been held at the proper temperature that the right amount of acidity may have developed in it. The cream should have an acidity of from .3 to .5 per cent and be held at the tempera- ture required for churning at least two hours before churning. The churning temperature will necessarily vary in the different seasons, but should run about 52-54 in the summer and 54-58 in the winter. The churn should be thoroughly scalded out to remove bad odors or taints and then cooled down with cold water. The cream should then be weighed and placed in the churn and the churning process started. If a barrel churn, churn until the butter begins to break in small granules about the size of a grain of corn. Here the churning should stop. It should take not over 30 minutes to reach this stage if the cream was properly handled before starting to churn. If it takes less than 15 minutes it may mean that the churning temperature was too hot. Draw off the buttermilk through a sieve that the small particles of butter may not be lost. Take the temperature of the buttermilk. Pour over the butter, in the churn, about the same amount of water as cream used in the churning and from 4° to 10° cooler than the buttermilk. Rinse the butter in this water for about 15 to 20 revolutions of the churn. Draw off the water, and take the butter out on the working board and salt, using about one ounce of salt to the pound of butter. The salting may be done in the churn if it has a worker. After salting, allow the salt to dissolve, then work the butter until the salt is in all parts and the buttermilk is out. Print and wrap in clean parchment paper. Wash and seald all utensils and leave hot to dry. Student A. Weigh out the cream for churning; get the temperature right, add butter-color if necessary, place cream in churn; make all necessary observations, record data; scald the butterworker and other wooden- ware and then chill thoroughly with cold water; get the necessary rinse water and have it at the right temperature. Weigh the salt and have things ready when churning is done. Draw off buttermilk, rinse butter, place butter on worker, salt, work and print. Finish recording data. (Record all data on the following page.) Student B. Scald the churn with hot water and then chill thoroughly with cold water. Run the churn, take samples of buttermilk and wash up the churn. In washing up the churn rinse with luke-warm water and then wash thoroughly with scalding water and washing powder and EXERCISE 32 (Conrtinvep) (53) seald with clear water. Use brush on the outside of the churn. Leave the churn hot. Wrap the butter, wash the butterworker, other wooden- ware, and pails in the same manner as the churn was washed. See that the floor is clean and dry and that each piece of apparatus is clean and in its place. Unclean or misplaced apparatus will count heavily against good butter making. CHURNENG RECORD —Chiurning: No; cos 2226 ae eee This blank should be neatly and accurately filled out when the product is finished. PON GIGLOMNO I CLEA Ina eee eae net Sek i etee Fhe kee er mee he ek Wines a oe ay ea Bia AgOUNGS (Ole terlme aa tras oem Se satiate, sar ee Blecstaie crac ele Hap eters caw Duadewihclnewes Temperature at which cream was ripened “TEAMTU SHO) Ti OLN eels we Goeeniasg whe whoa WS romeo SMSO ep RCO OR ca ae eee ee eae a ne Length of time held at churning temperature © of fat in cream when churned Kkind and size of churn usec Approximate fullness of churn Temperature churned “IPSS aNE) SHO yaCG) ONDA a sey bse ye ns es gy aaa CIO PHC es CR aad en ee Size of granules when churning stops Hemera ULE TOMO Ut ueriannl Kea seinen ne cicun cess cists Siu Test ENT OUNULOMWAS MEW tChee et apne ree Ani Vera etn sen G2 cee Eee a cg Me Soa Temperature of wash water Amount of salt used Brine or dry salted Butter from churn hard or soft ee pov ad o) el elsaler eo] vie: ©). 06] ,0)/0 16 16, 6.0 ©,eke 0 ‘eles eee 6 0 \0 © 6.6 616) 6)0 6.6.0 0,/0 ee, 0 6 016 Pounds of butter Wiel OVsikeN eile) e)\e! ah aie! ee) efere" 6.6) 6'jereXelere eke. silajie/e\(e 60 e's. 260 0.6.0: «0,0 sce 0.0 0 6, 06 © 0160.0 0 0.0 06 ee Ste" eV 6) ene} (6.6 eee 0! fel ef exe le lu .eticl el 6.6, 61h610 (6)'6 (0.0 «0.1618 6)/e, 6. ice \e iahele(e; 076 600 os: 0 «see 610)0'\a"4 0 .e0'\6 © overrun CECE Suey 0/0/16) a\ a) ate ee lee eee) \e)(e] eel.e)ee\e) ele) ¢| e604) 61\e.je) 01 6 | \0)'0, 6.6.66 0.6 8 oie eel. exe @ 01's! ele, 40 oye) -0, 9lacere Work and observations by Assisted by Make special notes regarding this churning operation. Grades S232 oe oo eee BA Ey ois (54) EXERCISE 33. Oxssect.—To churn and make a good grade of butter from well ripened cream. (Second churning exercise.) AppaARATUS.—The same as for Exercise 32. Step 1. Follow closely Exercise 32. (The two students may trade work.) CHURNING RECORD: —Churning INOvstee sete «lcrteeiels This blank should be neatly and accurately filled out when the product is finished. Conditiontoiceredintys eee ee ae a cere aot econ saa Soave §o master CC an eee coe Dotal Pounds lage ofp sercvcc cup Sa 8. che cpa, Sere. kal oni esos Pets enwuens Corot ee errata Temperaturesat which cream: Was TINE ...2-.. 0: s).,-\sie1c's o iyaitie tie ere eeeyee tree ey ere ean Dias RONS Ht Of2) tid ert ic eee RG ECM Cor ASRS ni er eR ns eRe AIA mR MAT OT he pata d Lengthyof time held: atichurning temperatures: 7 s.42..)s-,5 sane eioeisre oe ates nie ie ete ee COL tavanecreamMs when tGhurned cyrse ccras sey earn iere eerie en ree ie ee ee eee Kind andsizesot chur vised 25 sf.oa 1's. caters anetespe tani e ty eters, 2 che ae ee cet Se ee ee Approximate fullness of Churn) Noi aelgsssin«, ele viale eae ese ches chew seesiale yc Reet a tere emperature chtrned 4. here. o/s vis este terete uta cet ionse sob age he Acs Pee ea aad awe oer ime ‘GOPChurnes. tec eeks ehh I kc ee tc sae one oN ete eae ae eee Size. oheranulesiwhenvchtnnineistopse ra cc sme section tei ects nie recite ie eine ene shemperaturerohbuttermil ken errecr me tac eee tee eae SROSESE.; teteveters tent tare aaieteeere AMOUNt (Of WASH WALED. cs 53 sate clecertenseneceee etete tel es sient otekeie ter ile oar aoe eeoclcke tee oaks Caer eemae Temperature of wash. waters: .. svat csten wis se sates ©) icra ccsre.s 2 Sap oo) ofapele Seige esaaslid peat ater AmOuntrOL Salt-USed Hie tes Soa ceoteasetynora cles pict eooctensces Chae oe eee RUTe Crates aC ee a Brinesor dry salted y. core xatrechus ocr ve re tal aig cleaatei toc, sigan dye cr sttiteee gaia eres eat ee tak eee Buttersfromchurnvhnard\ ors SOltwe cms estes eeeig eicte re ale tone cle orVaateaa ieee nee eerie Poundsrofsbutteray.c yee ciate eae ens ee oe Niele hike ete ote ee Oe eee Pounds Of overruns. 87 ciara assists 2 Go eee eR Sra ie Beets Fae SEO EEO coe eee ig AR Oi 61's GLU 00 On RE CAN Pies SE nS mn Meat ey ier Eat ea NLT ENP eye Biloiwid 2.0 .c Work and observations) Dye css eee ence en caetein ere rae ee MOLES Went s S ASSISLE! Diy s ot ot th, oad Bias vac vath are poe Te aie store, 4 aah aac Ee AS atin eta ne ae oats Make special notes regarding this churning operation. rade @] ey ee eiomt @ ‘et valieve ne le se: 8) ee \s) fevie he .s 6 felte, edeiie ieee. ere knee rw ek ee oe EXERCISE 34.-: (55) Opsect.—To see the effect of churning at a high churning temperature and washing at a low temperature. AppARATUS.—Same as for other churning exercises. Step 1. Have temperature of cream at 58° to 60° F., rinse water 45° to 50°. CHURNING RECORD:-—Churning Nowis...6s.s0c0e.0s This blank should be neatly and accurately filled out when the product is finished. GGndiONeOeChCA ln Meee Sr RNa tas cone he fere oo av otieh/s sianelel Gane hin srsleles RUE eis e Total pounds of fat Temperature at which cream was ripened Time to ripen Length of time held at churning temperature % of fat in cream when churned Kind and size of churn used Approximate fullness of churn Temperature churned CIR TTNERUORG INIT Semen atom ee mers rten ee pet ae rete Tet f eo nty cre tsp apale are sel cae Wiahardeo.9) oueue. aeapeseue o,fehe Gyo ¢ "oes Amount of color used Size of granules when churning stops emperaturerOL buttermilk 2.5 )2 10 sla. lcre ieee le cies ae nies Test FATTYOUTUERO HWS ITV C eee ree Rta ver tae ocean eNS uate rat aise) cc steko lcmeia Nehans loledoacsraue sine eionete oie» ois steve Temperature of wash water me ont alial a larenmpeeleleieheleie ala.é} anal s eT © 10,,0, ¢ (eee; 6,066) 0/4) 016, 0.014) @ i 61 076) 4.6/0) 6h e Amount of salt used siallatelene. sl cis eletete aceke: 416 aj a%6 a .a08' (6: (6) 01.0) 0! (01,619 6,,0, 046) 0.00 6) 0 @) 0 fe le:1e..6, ag6).6) 0, 0 jeite'e! 0: 6) 019, 6) eke Brine or dry salted Butter from churn hard or soft Pounds of butter ciahallelicl Castel elu elenocevelel ic siie ee ele) elej'slteleje 1610) 0) ,4/(0) 6.166) 6.06) 6.6) 6) 6) 610 (0706; C119 4, ¢ ¢. 6.078! 00, ¢..0,0 6.058 Pounds of overrun atetatchec)'e ele sletbiele te. ol @ ies Lele. eo iéle_ ole, 0 d/o lel. .0,/8) 60 6, 67:0) 0110 10 )0s'6, (0/18 10 0) Chore S00. 07.6.6) .6 68" 87 01a Le % overrun Eee otel aie a laitserie ala levers hele et nieie? ba law iefe\ te .0/{e,(e) alee! 6.6 le 6 616 0.6.0 6 00S 6. 8:8) 61/67) 9 67-0: (00 FeO) 0) \0 Bie! ee ae e Work and observations by Eiculetaettelsilelisiiel shel lee), 6! 3/i61e)6) 01,0 6 a0) 00e la) heehee! eyo) 815, Oe) 6 67.00, 6: 6) 0.6.0) 0.6 4) s, 5, 8.0 PRESSES UC Ola Faye ema RENE ePIC ol oPe ores urge. eV, en e/pieie ois ein oid gees «Stal s\ cle se) cin ols gic & ost Make special notes regarding this churning operation. @ras15 (Lemna urs iiiyirer Men ees neo (56) EXERCISE 35. OssEct.—To see the effects of a low churning temperature and a high wash- ing temperature. APpPARATUS.—Same as for other churning exercises. Step 1. Have cream at 48° to 50° F.; rinse water 56° to 58°. Write fully the evil effects of the above practice. CHURNING RECORD —Churning Noes oars sins This blank should be neatly and accurately filled out when the product is finished. @ondition (ofcreameee ee sc vase ce tokectne Chuan ls are a ier eae Ge ee Motalwpound ss olivier ee ccpes ears cuss wits Or eeeato-s Veo de hs /5 lad aie Se ease ret ee eee ner CE Pemperaturevab which creamywas ripened 21.5. <.0o..025)-2 os fom,s em ols slp ee eee A oben eyo ies ote e marberin cece ican eRe ate Pict ae a ior Monae ROS COM OSs hewro0B,0 ode oa bc Length of time held at churning temperature % of fat in cream when churned Kind and size of churn used Approximate fullness:Ob ChUris 5. ciawic oiaris st seereasrentte hays eaeronete se aisuetehererstcte mata skeet nayers ERE PCTALUTE CHUTE bya ieter Sched. oy 5 ain ete occa chal Astrea do cadeael at elec s Msetiona auto siete aecet tee fee oy tee SDriocYsyan ova) Oba diario Sanh Oe oe erie ay in kin iniratro cieciou dd cng Wormdciac KOS tole Solon é jadaTaLVLOUPCoVEN Ole) (8) aA vIIe Mme EO RRO ara Wa ts eped.tc eicicts caoeno ais Ge OGnoo coe Ghb onus Size of granules when churning stops....... Temperature of buttermilks oe ce oes seis wie sas eae Testis tac seater aot ca Oe Amount.ofewashu waibeln rr cpcct-solcne.cuckele:seeteus Gite vonoteekereue ouckovaueters port stave Mima da eoler fone a meres Temperature: of; washi waters is. ceramic tesie ister one forsisiialess breve letra e+ asain tok ieee cor cners Amount4ob sal fased See crs, 25ers Bees etek cone aero dos Sale pee Sue Peco are Brinevor dry Salted: cgices.cs ccc tonscscehode se epeek thers eee wince merrcaspateiere ce omdale cPalers Crane vee ecm teeter Butteriromechurmphardtormsolbecewemin rye acim ee eters cine rare Pounds sof biwtter ssi pe ysvcharacsoteve oh acres cee sarah s aoe oral Sota Pe eae te ie ete ere Sea oeee Pounds of overrun @)'e cele ie] je 00 © @ 050) ©] B's. 670) v, 6 6 6) alee @ 6 © 0 ce) vuole ele elie 6, 6)\o.010\e: ee lake @)\s1(¢ oe elelve sels) 6s % overrun eo cle «6 afene 0 eo wie le wilelfelie «ie 0, 00,0) e1.0 60 es. ous) oe. oe 0: e010, 6) (8i\e.,6).0' e, © [eco (e eels! 07.06! ere (elle! 0:1s\"e) 61ers. si eve, re Work and observations by 6, (87 \\0,'0) 10) 0.0 (0) © 0! 03 6:0) 6,0 |,s \e)e101.0),6 (e\xe!'01,0) 10) (0; e\{e(ei'0/e 0) \e| (0, (00 Fe. (0! w\ Le) (0116/1811 61 6,8 (0; (6 16/01 4) 6 Nee DANSET i o16 bil 0) GENS ae CR eRe er ta ent As ars ty aii ah BiG Oe Oa aeRO Make special notes regarding this churning operation. EXERCISE 36. (57) Oxssect.—To determine the effect of churning very thick cream. APPARATUS.—Same as for other churning exercises. Step 1. Have cream 35 to 40 per cent fat. CHURNING RECORD.—Churning No.....+...++6- ne This blank should be neatly and accurately filled out when the product is finished. Doni One Ole Clen i. eee ete ec ah Pe tens coe awa iw iscecstote Oie'c ar cteveiela, ate sve gavalsosimeanaing Me uplpPOUNGS Of ts brekes ae setens fia: alate cordhane Finsavele a cea as edre Sie SS Sino OAR slalnle eds wie visio was Temperature at which cream was ripened .........-.---- cece cece eee e eee eee e eee eens Tbitiend Gagne tal Ge aere geeekceaher atic yore eI nue icatct torie o ear ee e Length of time held at churning temperature. .......-.... sees eee e cece reece eee teens % of fat in cream when churned... <2... 00.05 s2eceses ccs e cece eee ere rece eeesenees GVEA EST ZENO LAC HULU SG CL rane Pepe nett melcun trate apni esjcove: 2yat ctu) alof'sNe!e! ors eke elas w/eshezeneuesei oss Approximate fullness: of Chur s)fuss eee tdie sinew sore aaa secs oot he hee e eee ae eels ai ane Memperatware: CMUENEG. <2% 5 cleisia tia soe due.sialmie'e els Wales e «injein Gale + cleans oo 604 ead eisieecin ss sedis EIEINGRLOEC INUIT MPN eens ure aes aisle etter sofa eh ctieser spears! seassler ce: sisi eva 2% vires! 01 $.@7i0'-s el af: ele 3 ile ous PUTTER ROR COL OTNUIS CO tere el ence sich vaca rene apa spaniel Oks ila. ile. w thes «5.9, 4.9°6'e ara etateceielw aos Size of granules when churning stopS.....0... 002 ccc c cece cette eee ee cece neces ee ennecs Temperature of buttermilk... .........0ccesecceseseceees ADO Ud gece shayd atch cultivates ee eens PATITOUTIGE OLa was lit WiclUC Lami reeeceae tenets cParshecceereimic sscveie cu avens iecsic, © oiiera)ni, © ae olais mie sidusiela ieyenstedars Memuperature: Of WASH WAGED... 65. sietinscwts asta ccslenescindeceeensesederensesseees PITTOMTNGCOL 1 Sel CHSC setae nase hees cco: ora ob acara foinse e ictet Sumsof tie cians a bs sha. 89 8 b:e ai Giuisie gS Fe A mass 558 Beale ETN GN GLC ey eeHll LEC meter Manat etack se ieverata: 018 arehala coin oielths oat e,f)e12 aac's S:o:nic. wisieeigidle dae aves ae'e ¥ ans BRE Ler she OM CHUrM NATGVOL VBOLG 2 kic.ctere oii ciesisnc|sparele-@ Eo eine oles 0:4 6% 0 isuele/vielpie else a ee. wo ever JP2oribays eral al Sib Hise Se ee ee Sean MeN Mir hes qc] SCR ee eee ee eee ee SOUINOaGhinG V.ELIUT ete ceee cone oie oO ivr. catia eysteie’ «lafas| aise ete in is.0'shereiges ails pe ardiw nue ane aya SE POMCEGUM erate beget pei ene rahe Ge aeid er cagseeetel eye vesevers! fie (a8e, 6.0. s)'s'« wteis ae eos be © emis ¥ Sieh. sstene Work and observations by ops heteletiele, sist el bbe) ehenekeye, et ete) eKelel 6. e) 6:6 © 6.10) 6.'6:.6) © 6) 6 ©) 4) 8.0/8: © 6:14. 0, (000, © ©..0) 00.0 8),e AETEUGSL 55 on GORD Rois DEES SBR aC UR Oe S Ce Ee oe ee Cea Make special notes regarding this churning operation. (58) EXERCISE 37. Ossect.—To see the effects of over-working butter. APPARATUS.—Same as in other churning exercises. Step 1. Churn and otherwise care for the cream as in the first churning exercises until the butter is ready to work. Step 2. Work butter until it seems to be worked enough; note its condition. Break a few lumps and note the grain. Then continue working, noting the condition of the butter every five revolutions of the worker. Con- tinue working until the butter is much over-worked. Record data. Whelllsworcece eee Brees ee eee ese eee Ea EE ee One EO ee ee Nd ditional oamev OlutlonSievas.s oc eis crceesrsne etree ean Uke eee Te ne eee a TQ ¥rev.OlUtiONSy. cesses Sey ere re oe a en ae eee Ona ee oN cee ee Pe VOMIIEIOTIS Stee toe stots teeth tes oe Pe On seen Cag eer ene ace ee a FM TETOLUPGIONS sce vines G5 vith SSN ye ee Pe se ec se ee Rete er STOW OLUItIONS: Sele tehe cco e ie OO ee ee eee Te ee eater nr re ee pde eae ae ee ee Si) revOlutiONS:s Misses bie re ee ee Le ae Ae ORE EOS Tee eer eee Py tisollvi nite] 0: pene i ene RA eee ES RR a GAR ine clio moAaid mid Gwe doo 4 oo aides Make special notes regarding this churning operation. Make record on following page. EXERCISE 37 (Continvep) (59) CHURNING RECORD:—Churning NoOiss oe tai atonciovecs"otsachelc rel suereleMe pe] Choate aerate Buttersfrom\churnvhard or mSOLt seperate ocieccter teterteioreietiay- Se a Sa Bi calle os Sey cae cee emperature ols bubtermille. So oo54 oes vs sk aisles oo ¢ Regt sis stats eeiers eae NEVO UUELUPOL e Vers EN WY GCI cree rey Eiger yA ete Bebe aly lay e fah ld cheat olan Se/ ecehdusr ale canes’ e wide Wate Ghuah wees SEMIMELAUUILLS Oly WAS EW ALC MeN sty aie ne tea Oe chials vale