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RTMENT OF AGRICULTL

_ BUREAU OF PLANT INDUSTRY—BULLBTIN NO. 40.
: ae - B. T. GALLOWAY, Chief off Bureau. i: :

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| COLD STORAGE, WITH SPECIAL REFER
| . ENCE TO THE PEAR AND PEACH.

fps eel ic BY La ee

2) HAROLD POWELL

Assistant Pomo.oeist In Cuarcr or Kirip INvESsTIGATIO

ch

Po hee NUP oe , ‘ SAND
'S. H. FULTON,

ASSISTANT IN PomoLoey.

©. as x

POMOLOGICAL, INVESTIGATIONS. :

Issurp SerremBer 18, 1903,

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WASHINGTON (000 #9 Uae
ete GOVERNMENT PRINTING OFFICE. cf oaks SING Saas
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| a ae Gardens and Gr ounds, aa of one were a bara
mei and also: Seed and Plant: Introduction end Distribution, the eae oe p

me No. sie ‘The Relation of Lime. ined “Manede to Plant Growth, »L Liming: of So
me from a Physiological Standpoint. I. Experimental Study of the Bee
_ of Lime and Magnesia to Plant Growth. 1901. Price, 10 cents. — ,
meenae 2. Re jeraukstonbats and Fecundation of: Zamia. 1901. (Price; 20 cents.
a ae 3. Macaroni Wheats. 1901. Price, 20 cents.
4. Range Improvement in Arizona. (Cooperative Experiments wae the ri
zona Experiment Station.) 1902. Price, 10 cents.
6. Seeds and Plants Imported Through the Section of Seed and Plant. Intro:
—- duetion for Distribution in Cooperation with the Agricultural Experimen
% é - $tations. Inventory No. 9, Numbers 4351-5500. 1902. Price, 10 cents. a
~~» 6. A List of American Varieties lof Peppers. 1902..oPrice, 10 cents. S29 77 Si
7. The Algerian Durum Wheats: A Classified List, with Descriptions.
Price, 15 cents.
Gee Collection of Economic aod Giher Fungi Prepared for Distribution.
“Uv . Price-10 cents. tg
9. The. North American Species of Spartina. 1902. Price, 10 cents. Ui
10. Records of Seed Distribution and Cooperative Experiments with Grasses a
Forage Plants. 1902.. Price, 10 cents. .~
ara Johnson Grass: Report of. Investigations Made During the Season of 1901, %
Poy 1902. <-Price, 10° cents. a
aie. Stock Ranges of Northwestern California: Notes on the Grasses and Forage:
| Plants and Range Conditions. 1902... Price, 15 cents. Rae
“1B. Experiments and Range Improvements i in Central Texas. 1902. | Price, ai
Ba aS A een ts. fe
i 14. ears Decay of Timber and ‘Methods of Preventing Mtl 1902. Price, 5b cents, :

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eyes Report upon Investigations Made During July and Aaa 1901, 3 in ‘the
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05". ¢Control, Il. A Cowpea Resistant to Root Knot (Heterodera Radicicola).
1902... Price, 10 cents. te:
18. Observations on the Mosaic Disease of Tobaceo.. 1902, Price, 15. cents, ee
, 19. oe es Bluegrass Seed: Harvesting, Curing, and Cleaning. Be Price,
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20. Manutachire of Semolina and Macaroni. 1902. Price, 15 cetas cap ah
21. List of American Varieties of Vegetables for the Years ee te 1902.
pe See ties 35 cents.

[Continued on p. 3:0f cover.)

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Bul. 40, Bureau of Plant Industry, U. S. Dept. of Agriculture, PLATE |.

ELBERTA PEACHES, STORED FOR TWO WEEKS IN A TEMPERATURE OF 36° F. (UPPER
FIGURE) AND 32° F. (LOWER FIGURE.) NATURAL SIZE.

oo Diva i vMENT OF AGRICULTURE.
BUREAU OF PLANT INDUSTRY—BULLETIN NO, 40.

B. T. GALLOWAY, Chief of Bureau.

COLD STORAGE, WITH SPECIAL REFER-
ENCK TO THE PHAR AND PEACH.

BY

G. HAROLD POWELL,
ASSISTANT POMOLOGIST IN CHARGE OF FIELD INVESTIGATIONS,
AND

Se Ee UE LON,

ASSISTANT IN POMOLOGY.

POMOLOGICAL INVESTIGATIONS.

IssuED SEPTEMBER 18, 1903.

Nw

WASHINGTON:
GOVERNMENT PRINTING OFFICE,
LA DOROr,

BUREAU OF PLANT INDUSTRY.
B. T. Gauttoway, Chief of Bureau.
POMOLOGICAL INVESTIGATIONS.
SCIENTIFIC STAFF.

G. B. BracKkerr, Pomologist.

Wma. A. Taytor, Pomologist in Charge of Field Investigations.

G. Haro_p PowEL.L, Assistant Pomologist in Charge of Field Investigations.
H. P. Gouxp, Assistant Pomologist in Charge of Fruit District Investigations.
GEORGE C. HusMann, Expert in Charge of Viticultural Investigations.

S. H. Fuuron, Assistant in Pomology.

PER Obs ANS MITTAL

U.S. DepaRTMENT OF AGRICULTURE,
Bureau oF Puant InpustTrY,
OFFICE OF THE CHIEF,
Washington, D. C., May 11, 1903.

Str: I have the honor to transmit herewith a paper entitled ‘‘ Cold
Storage, with Special Reference to the Pear and Peach,” and respect-
fully recommend that it be published as Bulletin No. 40 of the series
of this Bureau.

This paper was prepared by Mr. G. Harold Powell, Assistant Pomo-
logist in Charge of Field Investigations, and Mr. S$. H. Fulton, Assist-
ant in Pomology, and has been submitted by the Pomologist with a
view to publication.

The illustrations which accompany this report, comprising’ five col-
ored and two half-tone plates, are considered essential to a full under-
standing of the text.

Respectfully,
B. T. GaLtLoway,
Chief of Bureau.
Hon. JAMES WItLson,
Secretary of Agriculture.

Go

eke eC he

The protection of fresh fruits, through the agency of low tempera-
tures in cold storage houses, against their normal deterioration and
decay has become in recent years one of the most important factors
affecting the prosperity of the commercial orchardists of the United
States. Practical experience has demonstrated the necessity for more
complete and accurate knowledge regarding the possibilities of pre-
serving fruit in wholesome condition in this way and the underlying
principles that govern the behavior of fruits thus stored, as well as
the effect of different cultural and climatic conditions upon the behavior
of stored fruit.

The investigation of different phases of this subject was begun in
the summer of 1901 and is still in progress. While the completion of
these important investigations, which involve repeated experiments
with different varieties of fruit grown under the varying climatic con-
ditions of different parts of the country and stored in different ware-
houses, will of necessity extend over a considerable period of time,
the important economic results thus far attained make the publication
of this preliminary report upon the subject advisable at this time.
In this report certain general principles are stated for the benefit of
fruit growers, dealers, and storage men, and such specific application
is made of these principles to the peach and pear in storage as experi-
ence thus far has proved desirable. Other phases of the work are in
progress and will be discussed in future publications.

This bulletin has been prepared by Mr. G. Harold Powell, Assistant
Pomologist in Charge of Field Investigations, and Mr. 5. H. Fulton,
Assistant in Pomology, as the result of investigations made by them
under the direction of Mr. William A. Taylor, Pomologist in Charge
of Field Investigations. The work, in so far as these fruits are con-
cerned, has been closely associated with the experimental export ship-
ments of fruits, which will be reported upon in a future bulletin.

G. B. BRACKETT,
Pomologist.

OFrFIcE oF PomoLogicaL INVESTIGATIONS,

Washington, D. C., March 19, 1903.

CONTE NICS.

Page.

Mneaiinichlonol colds storage ss: 25.3. 2-06 ea tee eek Le cee eee 9
Meg ouEpoOsesvonminultstorages 2.26001 ooh eS a ee 10
imMilwence Of cold'storage:on the pear industry #22222 /0222 223 252 bis 11
rccuical. diunewlttes im pearstOrage 2552. 22.08 he! eee ens 11
Outlineoexperiments in pear storage. 225 2 ses fae nee ee oe Se 12
The influence of the degree of maturity on keeping quality ..........--- 13
The influence of delayed storage on keeping quality .........--.--.----. 14
The influence of different temperatures on keeping quality............-- 15
The influence of the type of package on keeping quality.............--. 16
The influence of a wrapper on keeping quality ........---.--------..--- 18
The influence of cold storage on the flavor and aroma of the Pant te ; 19
The behavior of the fruit when removed from storage ............------ 20
STON DOU OVEN AY RS Sis ASE 8 ee GN cg Ao sear eee 21
imiuence ot cold storage on the peach industry --.-..!.-2.-.----..---+----- 23
Practical difficulties in peach storage... --.. Toren serene MIE Me ontans Cyd 23
Minulineotexperiments im peach storace = 6 22224. 2- 2). : 24
Generalsstatement ol results. fo. 8 wt ea oe ee knees ee tied cides eae 24
WESCRIOUOMeOlap ALES aye eens eee een eee Sees ae eit ee 28

7

PLATA SaEeATE Oss:

3 Page.

Pirate J. Elberta peaches stored for two weeks in a temperature of 36° F. (upper
figure)-and 32°2h4(lower eure). 22 eee Frontispiece.

‘Il. Kieffer pear, March, 1902. Fruit picked October 21, 1901, and
placed in storage the following day at a temperature of 52° F____- 28

Ill. Kieffer pear, January, 1902. Fruit. picked October 21, 1901, and
placed in storage ten days later at a temperature of 32° F_____.-- 28

IV. Wrapped Kieffer pears, removed from cold storage on March 38, 1902.

Fig. 1.—Fruit in both boxes picked October 21, 1901, that on the

right being placed in storage on the following day at a temperature

of 32° F., while that on the left was not stored for ten days. Fig.

2.—Fruit in both boxes picked October 21, 1901, and stered on the

following day, that on the right at a temperature of 32° F., and that
on: leftiat' S602 R 2 joes oe Nee oe ee eh a 28

V. Kieffer pears, March 3, 1902. Fruit picked October 21, 1901, and
stored on the following day at a temperature of 36° F__.....-.--- 28

VI. Bartlett pears, one week after being placed in cold storage. The

upper figure shows the average condition of the fruit in center of
barrel; the lower figure, that near the outside of the barrel ....-- 28

VII. Kieffer pears removed from cold storage on January 20, 1902. Fruit

picked October 21, 1901, and placed in storage on the following day.

Nearly 50 per cent of the unwrapped fruit decayed, while that
wrapped in parchment and news paper kept in perfect condition- - 28

8

B. P. 1.—58. Pom. I.—17.

COLD STORAGE, WITH SPECIAL REFERENCE TO THE
PEAR AND PEACH.

THE FUNCTION OF COLD STORAGE.

Fruit is placed in cold storage to retard the life processes which as
they progress cause it to ripen and decay. The ripening goes forward
more slowly in low temperatures, but still continues in the lowest tem-
peratures in which the fruit may be safely stored. Fruit is stored also
to prevent the rapid spread of fungous diseases which cause its prema-
ture decay.

A fruit is a living organism, with a life history extending from its
earliest growth to final decay, and the cold-storage treatment is
designed to retard development: without injuring its usefulness in
other respects. The rapidity of ripening in the storage temperature
depends principally on the habit of the fruit, the degree of maturity
at which it enters the storage house, and the temperature and other
conditions in which it is stored. It is influenced also by other factors
during its growth and by the treatment it receives before it reaches
the storage house.

The warehouse is expected to supply a uniform temperature of the
desired degree of cold through the storage compartments during the
storage season. It is expected to be managed in other respects so that
an unusual loss in the aroma and flavor of the fruit, in texture or in
color, or through decay, may not be attributed to a poorly constructed
or installed plant, or to its negligent or improper management. If the
temperatures are maintained reasonably uniform at the point desired
by the fruit storer, if the rooms are kept pure and sweet and laden
with sufficient moisture, and if the fruit is handled properly within the
warehouse, the storage house fulfills its function in the preservation of
fruits. If, on the other hand, the temperatures fluctuate unduly and
the fruit freezes to the point of injury, or is made to ripen prematurely,
or the rooms are not properly managed, or if ordinary care is not exer-
cised in other respects in the management of the house or the handling
of the fruit, the storage house fails to fulfill its proper function.

The warehouseman does not insure the fruit against natural deteriora-
tion. He holds it in storage as a trustee, and in that relation is bound
to use only that degree of care in the management of the warehouse

9

10 COLD STORAGE OF THE PEAR AND PEACH.

that a man of ordinary prudence would exert under the circumstances
in protecting the goods if they were his private property.

It is frequently assumed that the cold-storage house in some mys-
terious way levels the differences that naturally exist in the fruits of -
a given kind, causing all.the apples of a variety, for example, to keep
alike. No assumption, however, could be more fallacious, and it is
probable that no one aspect of the storage business has led to more
misunderstandings between the men who store fruit and the ware-
housemen than this unfortunate impression. Cold storage can not
improve the physical condition of fruit, and is in no way responsible
for the deterioration that may arise from improper picking, grading,
packing, and handling before the storage house is reached.

Fruits of all kinds are profoundly modified by the climate, the soil,
the age and health of the trees, and the conditions to which they are
subjected during their development, and these acquired differences
will manifest themselves in the storage rooms just as they do in nor-
mal storage ripening, except that they usually appear later.

THE PURPOSES OF FRUIT STORAGE.

In the consideration of any storage problem it is important to pay
due attention not only to the influences which affect the keeping
quality of fruits and to the function of the cold-storage plant, but also
to the purpose for which the fruit is stored. The fruit dealer may not
always desire to retard the development of the fruit to the greatest
possible extent. For the Holiday trade it may be advisable to have
certain varieties of apples or pears in condition for immediate con-
sumption during the Christmas season, though the same varieties might
be retarded until April if stored in a lower temperature. The
fruiterer who takes the fruit from the storage house to the fruit stand
from day to day may desire it to ripen and color considerably before
it leaves the storage house. The dealer, on the other hand, who stores
the same varieties in large quantities for export trade or for late
domestic markets has a different object in view, and the two distinct
purposes would influence the storage treatment of each. |

It is equally important to consider the requirements of the market in
the storage of different fruits. The commercial use of a particular fruit |
is limited principally to the season when people are in the habit of
buying it, and beyond that period the demand is restricted, unless |
there is a failure in the supply of other fruits that normally fill the
market at that time. It is possible to hold many varieties of pears till
late winter or early spring, but the usual demand for them at that time
would not warrant their storage in large quantities, as apples and
oranges are then at the height of their season. In fact, it is doubtful
whether it is advisable to store pears of any kind in large quantities |

INFLUENCE OF COLD STORAGE ON PEAR. INDUSTRY. 11

after the middle of November. For the same reason it is usually not a
good plan to hold apples in large quantities later than the Ist of May,
when fresh vegetables and the new crop of Southern fruits begin to
fill the markets. The general principles, therefore, which govern the
preservation of fruits and their relation to the markets can be under-
stood only when these various factors are considered together.

INFLUENCE OF COLD STORAGE ON THE PEAR INDUSTRY.

Before the advent of the cold-storage business the supply of summer
pears frequently exceeded the demand. ‘This condition of the markets,
which were demoralized in hot, humid seasons, pertained especially to
the early varieties, like the Bartlett, which ripen in hot weather and
need to be sold in a short time to prevent heavy losses from rapid
decay. The introduction of the refrigerator car and of the cold-storage
warehouse, together with the rapid growth of the canning industry,
has done much to improve the pear situation by artificially establish-
ing a well-regulated and more uniform supply of fruit throughout a
longer period of time. The pear acreage of the country has more than
doubled within a decade, and is enlarging the relative importance of
cold storage to the pear-growing business, though a large part of the
increase, especially in California, along the Atlantic coast from New
Jersey southward, in Texas, and in the Central West, is primarily
related to the canning industry.

Pear storage has developed most largely in the Kast. In New York
and Jersey City from 60,000 to 100,000 bushels of summer pears,
30,000 to 60,000 bushels of later varieties, and many cars of California
pears are stored annually. In Boston, since 1895 there have been
stored each year from 5,000 to 15,000 bushels of early pears, principally
Bartlett, and from 7,000 to 20,000 bushels of later varieties, such as
Anjou, Bosc, Angouleme (Duchess), Seckel, and Sheldon. In Buffalo
10,000 bushels are sometimes stored in a single season, and in Phila-
delphia from 30,000 to 35,000 bushels. While there are no accurate
statistics available and the quantity fluctuates from year to year, it is
probable that as many as 300,000 bushels are stored in a single year
throughout the country at large.

PRACTICAL DIFFICULTIES IN PEAR STORAGE.

There are many practical difficulties in pear storage. The early-
ripening varieties which mature in hot weather, like the Bartlett,
often ‘‘slump” before they reach the storage house, or are in soft
condition, especially if they have been delayed in ordinary freight
cars in transit. They may afterwards decay badly in storage, break
down quickly on removal, or lose their delicate flavor and aroma.
When stored ina large package like the barrel, the fruit, especially of

12 COLD STORAGE OF THE PEAR AND PEACH.

the early varieties, often softens in the center of the package, while
the outside layers remain firm and green. Frequently no two ship-
ments from the same orchard act alike, even when stored in adjoining
packages in the same room, and the warehouseman and the owner, not
always knowing the history of the fruit, are at a loss to understand
the difficulty. It has been the aim in the fruit-storage investigations
of the Department of Agriculture to determine as far as possible the
reasons for some of the pear-storage troubles, and to point out the
relation of the results to a more rational storage business.

OUTLINE OF EXPERIMENTS IN PEAR STORAGE.

The investigations in pear storage are of a preliminary nature
only. The experiments undertaken have been planned with a view to
determining the influence in the storage room of various temperatures,
of the character of the storage package, of a fruit wrapper, of the
degree of maturity of the fruit when picked, and of other factors in
relation to the ripening processes in the storage house, and also to
ascertain the behavior of the fruit and its value to the consumer when
placed on the market.

The Bartlett and the Kieffer pears principally were used in the experi-
ments, but several other kinds have been under limited observation.
The Bartlett represents the delicate-fleshed, tender pears, ripening in
hot weather, which are withdrawn from storage before the weather
becomes cool. The Kieffer, on the other hand, is a coarse, hard pear,
ripening later in the fall in cooler weather, and in which the normal
ripening processes are slower. It is a longer keeper, and like other
fall varieties is withdrawn in cool weather.

The Bartlett experiments extended through the season of 1902.
The fruit was grown by Mr. F. L. Bradley, Barker, N. Y:, in a twelve-

year-old orchard on a sandy loam, witha clay subsoil. The orchard |
is a half mile from Lake Ontario and is 50 feet above the level of the ©
lake. The fruit, which was full grown, but green, was picked early in |

September, and was packed in tight and ventilated barrels, in 40-pound

closed boxes, and in slat bushel crates. Part of the fruit in each lot |
was wrapped in unprinted news paper, and an equal amount was left |
unwrapped. Part was forwarded at once by trolley line to the ware-
house of the Buffalo Cold Storage Company at Buffalo, N. Y., anda

similar quantity was held four days before being stored. The fruit
reached the storage house within ten hours after leaying the orchard.

The Kieffer experiments have extended over two years. In 1901,
the fruit was grown by Mr. M. B. Waite, Woodwardsville, Md., in a
Norfolk sandy soil, on rapidly growing five-year-old trees, from which |
the fruit was large, coarse, and of poor quality. It was stored in the cold-
storage department of the Center Market at Washington, D.C. In

“th

EXPERIMENTS IN PEAR STORAGE. 13

1902 the fruit with which the experiments were made was grown by
Mr. S. H. Derby, Woodside, Del., on heavy-bearing ten-year-old
trees on sandy soil with a clay subsoil. The fruit was smaller, of finer
texture, and of somewhat better quality than that used the previous
year. It was stored in the cold-storage department of the Reading
Terminal Market in Philadelphia, Pa.

The Kieffers were picked at three degrees of maturity: First, when
two-thirds grown, or before the fruit is usually picked; second, ten
days later, or about the time that Kieffers are commonly picked, and
third, ten days later, when the fruit was fully grown and still green,
but showing a yellowish tinge around the calyx. In each picking,
part of the fruit was shipped to storage and was placed in rooms with
a temperature of 36° and 32° F. within forty-eight hours. Equal quan-
tities stored in each temperature were wrapped in parchment paper, in
unprinted news paper, and were left unwrapped. <A duplicate lot of
fruit remained in a common storage house ten days in open boxes,
when it was packed inasimilar manner and sent to storage. This fruit
colored considerably during the interval, but was still hard and appar-
ently in good physical condition on entering the storage house. The
pears were stored in 40-pound closed boxes and in five-eighths bushel
peach baskets. One hundred and fifty bushels were used in the
experiments.

THE INFLUENCE OF THE DEGREE OF MATURITY ON KEEPING QUALITY.

The experiments with the Kieffer pear show that under conditions
similar to those in Delaware and eastern Maryland this variety may
safely be picked from the same orchard during a period of at least
three weeks, or when from two-thirds grown to full size, and that the
fruit in all cases may be stored successfully until the Holidays, or
much longer if there is still a demand for it. It is absolutely essential
that the fruit be handled with the greatest care, that it be sent at once
to storage after picking, that it be packed carefully to prevent bruis-
ing (preferably in small packages, like a bushel box), and that it be
stored in a temperature not above 32° F. if it is desired to hold it for
any length of time. If stored by the middle of October, the fruit,
by the latter part of December, will take on a rich, yellow color when
kept in a temperature of 32° F., and earlier if a higher temperature
is used. The fruit may be withdrawn during the Holidays, and will
stand up, i. e., continue in good condition, for ten days or longer if the
weather is cool, and will retain its normal quality if the rooms have
been properly managed. While the later picked fully grown pears
keep well, they are already inferior in quality at the picking time, as
the flesh around the center is filled with woody cells, making it of less
value either for eating in a fresh state or for culinary purposes. These
coarse cells in the Kieffer and some other late varieties do not develop

14 COLD STORAGE OF THE PEAR AND PEACH.

in the early-picked fruit to so large an extent. Pears of all kinds need
to be picked before they reach maturity and to be ripened in a cool tem-
perature if the best texture and flavor are to be developed. It is a mat-
ter of practical judgment to determine the proper picking season, but
for cold storage or other purposes the stem should at least cleave easily
from the tree before the fruit is ready to pick. Many trees bear fruit
differing widely in the degree of maturity at the same time, and in
such cases uniformity in the crop can be attained only when the orchard
is picked several times, the properly mature specimens being selected
in each successive picking. This practice not only secures more uni-
formity in ripeness, but the fruit is more even and the average size is
larger than when all the pears are picked at the same time.

THE INFLUENCE OF DELAYED STORAGE ON KEEPING QUALITY.

Pears ripen much more rapidly after they are picked than they do
in a similar temperature while hanging on the tree. The rapidity of
ripening varies with the character of the variety, the maturity of the
fruit when picked, the temperature in which it is placed, and the con-
ditions under which it has been grown. If the fruit is left in the
orchard in warm weather in piles or in packages, if it is delayed in
hot cars or on a railroad siding in transit, or if it is put in packages
which retain the heat for a long time, it continues to ripen and is
considerably nearer the end of its life history when it reaches the
storage house than would otherwise be the case. The influence of
delay in reaching the storage house will therefore vary with the
season, with the variety, and with the conditions surrounding the
fruit at this time. A delay of.a few days with the quick-ripening
Bartlett in sultry August weather might cause the fruit to soften or
even decay before it reached the storage house, though a similar
delay in clear, cooler weather would be less hurtful. A delay,.of a
like period in storing the slower-ripening Kieffer would be less in-
jurious in cool October weather, though the Kieffer pear, especially
from young trees, can sometimes be ruined commercially by not stor-
ing it at once after picking.

From the experiments with the Bartlett and the Kieffer pears, from
which these general introductory remarks, are deduced, it was found
that the Bartlett, if properly packed, kept in prime condition in cold
storage for six weeks, provided it was stored within forty-eight hours
after picking in a temperature of 32° F.; but that if the fruit did not
reach the storage room until four days after it was picked there was a
loss of 20 to 30 per cent from softening and decay under exactly simi-
lar storage conditions.

The Kieffers stored within forty-eight hours in a temperature of
32° F. have kept in perfect condition until late winter, although there
is little commercial demand for them after the Holidays. The fruit

EXPERIMENTS IN PEAR STORAGE. 5)

grown by Mr. Waite on young trees in 1901, which was still hard and
greenish-yellow when stored ten days after picking, began to discolor
and soften at the core ina few days after entering the storage room,
though the outside of the pears appeared perfectly normal. After
forty to fifty days the flesh was nearly all discolored and softened,
and the skin had turned brown. The fruit from the older trees on
the Derby farm in 1902, which was smaller and finer in texture,
appeared to ripen as much as the Waite pears during the ten days’
delay. This fruit, however, did not discolor at the core and decay
from the inside outward, but continued to ripen and soften in the
storage house and was injured at least 50 per cent in its commercial
value by the delay. Plate II shows the condition of the Kieffer pears
stored in a temperature of 32° F. as soon as picked and withdrawn in
March. Plate IIT shows the condition of fruit picked at the same time
and stored in the same temperature ten days after picking, when with-
drawn in January. (See also Pl. IV, fig. 1.)

The results of the experiments point out clearly the injury that may
occur by delaying the storage of the fruit after it is picked, and empha-
size the importance of a quick transfer from the orchard to the storage
house. If cars are not available for transportation and the fruit can
not be kept in a cool place, it is safer on the trees so far as its ulti-
mate keeping is concerned. It is advisable to forward to storage
the delicate quick-ripening varieties, like the Bartlett, in refrigerator
cars. The common closed freight car in warm weather soon becomes
a sweat box and ripens the fruit with unusual rapidity. The results
show clearly that the storage house may be responsible in no way for
the entire deterioration or even for a large part of the deterioration
that may take place while the fruit is in storage, and that the different
behavior of two lots from the same orchard may often be due to the
conditions that exist during the period that elapsed between the time
of picking and of storage.

THE INFLUENCE OF DIFFERENT TEMPERATURES ON KEEPING QUALITY.

There is no uniformity in practice in the temperatures in which
pears are stored. Formerly a temperature of 36° to 40° F. was con-
sidered most desirable, as a lower temperature was supposed to dis-
color the flesh and to injure the quality of the fruit. The pears were
also believed to deteriorate much more rapidly when removed to a
warmer air. In recent years a number of storage houses have carried
the fruit at the standard apple temperatures, i. e., from 30° to 32° F.
Large quantities of Bartlett, Angouleme, and Kieffer pears have been
stored in 32° and 36° F. in the experiments of the Department. The
fruit of all varieties has kept longer in the lower temperature and the
flesh has retained its commercial qualities longer after removal from
the storage house. Bartlett pears were in prime commercial condition

16 COLD STORAGE OF THE PEAR AND PEACH.

four to five weeks longer, Angouleme two months longer, and Kieffer
three months longer in a temperature of 32° F. Plates I] and V show
the condition of Kieffer pears in March, 1902, in 32° and 36° F., the
two lots having received similar treatment in all respects except in
storage temperatures. (See also Pl. IV, fig. 2.)

In the higher temperature the fruit ripens more rapidly, which
may be an advantage when it is desirable to color the fruit before it
leaves storage; but the fruit in that condition is nearer the end of its
life history and breaks down more quickly on removal to a warm
atmosphere.

There is a much wider variation in the behavior of pears that have
been delayed in storage or that‘are overripe when they enter the stor-
age room at 32° and 36° F. than in pears stored at once in these tem-
peratures. In the higher temperature the fruit that has been improp-
erly handled ripens and deteriorates more quickly. The lower
temperature not only keeps the fruit longer when it is stored at once,
but it is even more essential in preventing rapid deterioration in fruit
that has been improperly handled.

THE INFLUENCE OF THE TYPE OF PACKAGE ON KEEPING QUALITY.

Pears are commercially stored in closed barrels, in ventilated barrels,
in tight boxes holding a bushel or less, and in various kinds of venti-
lated crates. The character of the package exerts an important influ-
ence on the ripening of the fruit and on its behavior in other respects,
both before it enters the storage house and after it is stored, though
this fact is not generally recognized by fruit handlers or by ware-
housemen. The influence of the package on the ripening processes
appears to be related primarily to the ease with which the heat is ra-
diated from its contents. The greater the bulk of fruit within a
package and the more the air of the storage room is excluded from it
the longer the heat is retained. Quick-ripening fruits, like the Bart-
lett pear, that enter the storage room in a hot condition in large,
closed packages, may continue to ripen considerably before the fruit
cools down, and the ripening will be most pronounced in the center of |
the package, where the heat is retained longest. The influence of the
package, therefore, will be most marked in the hottest weather and
on fruits that ripen most quickly.

In the experiments of the Department of Agriculture- the Bartlett
pears were stored in tight and in ventilated barrels, in closed 40-pound
boxes, and in slat bushel crates. After three weeks in the storage
house the fruit that was stored in barrels soon after picking in a tem-
perature of 32° F. was yellow in the center of the package, while the
outside layers were firm and green. Plate VI shows the average condi-
tion of the fruit in these two positions one week after storing. After

EXPERIMENTS IN PEAR STORAGE. if

five weeks in storage the fruit in the center of the barrel was soft and
of no commercial value, while the outside layers were still in good
condition. The difference was still greater in a temperature of 36° F.,
and was more marked in both temperatures in fruit that was delayed
in reaching the storage house.

In both the closed 40-pound boxes and the slat crates the fruit was
even greener in average condition than the outside layers in the bar-
rels, and it was uniformly firm throughout the entire package.

There was apparently no difference between the fruit in the com-
mercial ventilated pear barrel and the common tight pear barrel. |

With the Kieffer, which enters the storage room in a cooler condi-
tion and which ripens more slowly, a comparison has been made
(in 1902) between the closed 40-pound box and the barrel, and while
the difference has been less marked the fruit has kept distinctly bet-
ter in the smaller package. The fruit in barrels was the property
of Mr. M. B. Waite, and was under observation by the Department
through his courtesy.

There is a wide difference of opinion concerning the value of venti-
lated in comparison with tight packages for storage purposes. No
dogmatic statements can be made that will not be subject to many
exceptions. The chief advantage of a ventilated package for storage
appears to lie in the greater rapidity with which the fruit cools, and
the quickness with which this result is attained depends on the tem-
perature of the fruit, its bulk, the temperature of the room, and the
openness of the package. The open-slat bushel crate, often used for
storing Bartlett pears, with which rapid cooling is of fundamental
importance, may be of much less value in storing later fruits that
are cooler and which ripen more slowly, and it may be of even less
importance to Bartletts in cool seasons.

The ordinary ventilated pear barrel does not appear to have sufli-
cient ventilation to cool the large bulk of fruit quickly.

The open package has several disadvantages. If the fruit is to
remain in storage for any length of time its exposure to the air will
be followed by wilting, which, in fruits held until late winter or
spring, may cause serious commercial injury. The ventilated pack-
age, especially if made of slats, needs to be handled with the utmost
care to prevent the discoloration of the fruit due to bruising where it
comes in contact with the edges of the slats.

There was little difference in the behavior of the Bartletts in the
closed 40-pound boxes and the slat crates at the end of five weeks, and
it would appear that a package of this size, even though closed, radi-
ates the heat with sufficient rapidity to quickly check the ripening.
Therefore the grower who uses the 40-pound or the bushel pear box
for commercial purposes can store the fruit safely in this package, but

26073—No. 40—03

)

18 COLD STORAGE OF THE PEAR AND PEACH.

if the barrel is used as the selling package, and the weather is hot, it
is a better plan to store the fruit in smaller packages, from which it
may be repacked in barrels at the end of the storage season. While
this practice is followed in several storage houses, it is not to be
encouraged, as the rehandling of the fruit is a disadvantage. Rather
the use of the pear box should be encouraged as a more desirable pack-
age, both for storage and for commercial purposes.

The fruit-package question, as it relates to the storage house, may
be summed up by stating that fruits like the Bartlett pear and others
that ripen quickly and in hot weather may be expected to give best
results when stored in small packages. If the storage season does not
extend beyond early winter, an open package may be of additional
value, though not necessary if the package is small. But fruits like
the winter apples and late pears, which ripen in the fall in cool
weather and remain in storage for a long period, should be stored in
closed packages to prevent wilting. In such cases the disadvantages
of a large package, like a barrel, are not likely to be serious.

THE INFLUENCE OF A WRAPPER ON KEEPING QUALITY.

The life of a fruit in cold storage is prolonged by the use of a fruit
wrapper, and the advantage of the wrapper is more marked as the
season progresses. In Plate VII is shown the average quantity of
Kieffer pears in unprinted news paper and in parchment wrappers in
comparison with the quantity of commercial unwrapped pears in boxes
in January. Nearly 50 per cent of the unwrapped fruit had decayed at
that time. Early in the season the influence of the wrapper is not so
important, but if the fruit is to be stored until late spring the wrapper
keeps the fruit firmer and brighter. It prevents the spread of fungus
spores from one fruit to another and thereby reduces the amount of
decay. It checks the accumulation of mold on the stem and calyx in
long-term storage fruits, and in light-colored fruits it prevents bruis-
ing and the discoloration that usually follows. )

Careful comparisons haye been made of the efficiency of tissue,
parchment, unprinted news paper, and waxed papers, and but little
practical difference has been observed, except that a large amount of
mold has developed on the parchment wrappers in a temperature of
36° F. A double wrapper has proved more efficient for long keeping
than a single one, and a satisfactory combination consists of an absorb-
ent, unprinted news paper next to the fruit, with a more impervious
parafiin wrapper outside.

- The chief advantage of the wrapper for the Bartlett pear, which is
usually stored for a short time only, lies in the mechanical protection
to the fruit rather than in its efficiency in prolonging its season. Its
use for this purpose is advisable if the fruit is of superior grade and

EXPERIMENTS IN PEAR STORAGE. 19

designed for a first-class trade. For the late varieties the wrapper
presents the same advantages, and has an additional value in increas-
ing the commercial life of the fruit. It is especially efficient, if the
package is not tight, in lessening the wilting.

THE INFLUENCE OF COLD STORAGE ON THE FLAVOR AND AROMA OF
THE FRUIT.

There is a general impression that cold storage injures the delicate
aroma and characteristic flavors of fruits. In this publication the
most general statements only can be made concerning it, as the subject
is of a most complicated nature, not well understood, and involving a
consideration of the biological and chemical processes within the fruit
and of their relation to the changes in or to the development of the
aromatic oils, ethers, acids, or other products which give the fruit its
individuality of flavor.

It is not true that all cold-storage fruits are poor in quality. On the
contrary, if the storage house is properly managed the most delicate
aromas and flavors of many fruits are developed and retained for a
long time. The quality of the late fall and winter apples ripened in

_ the cold-storage house is equal to that of the same varieties ripened
— out of storage, and the late pears usually surpass in quality the same
_ varieties ripened in common storage.

The summer fruits, like the peach, the Bartlett pear, and the early
apples, lose their quality very easily, and in an improperly managed
storage house may have their flavors wholly destroyed. Even in a
room in which the air is kept pure the flavor of the peach seems to
be lost after two weeks or more, while the fruit is still firm, much as
the violet and some other flowers exhale most of their aromatic proper-
ties before the flowers begin to wilt. ;

It is probable that much of the loss in quality may be attributed to
overmaturity, brought about by holding the fruit in storage beyond
its maximum time; but it should be remembered that the same change
takes place in fruits that are not ripened in cold storage, the aroma
and fine flavor often disappearing before the fruit begins to deteriorate
materially in texture or appearance.

On the other hand, it is certain that the quality of stored fruits may
be injuriously affected by improper handling or by the faulty manage-
ment of the storage rooms. Respiration goes on rapidly when the
fruit is warm. If placed in an improperly ventilated storage room,
_ in which odors are arising from other products stored in the same
| compartment or in the same cycle of refrigeration, the warm fruit
may absorb these gases and become tainted by them, while the same
fruit, if cool when it enters the storage room, will breathe much less
actively, and there will be less danger of injury to the quality, even

| 3 : =

20 COLD STORAGE OF THE PEAR AND PEACH.

though the air is not perfectly sweet. The atmosphere of the rooms,
in which citrus fruits or vegetables of various kinds—such as cabbage,
onions, and celery—are stored, is often charged with the odors arising
from these products, if the ventilation is not thorough. In small
houses, in which a single room can not be used for each product,
fruits are often stored together during the summer months, and at
this period the storage air is in greater danger of vitiation, since it
is more difficult to provide proper ventilation.

The summer fruits, therefore, being generally hot when placed in
the storage room, are in condition to absorb the odors which are likely
to affect the rooms during the warm season, and as the biological and
chemical processes are normally more active in the case of such fruit
than in fruits maturing later, the flavors deteriorate more quickly,
even in well-ventilated rooms. The fruits that are picked in cool
weather and enter the storage rooms in a cooler and less active condi-
tion are not in.the same danger of contamination.

From the practical standpoint it may be pointed out that summer
fruits should be stored in rooms in which the air is sweet and pure.
They should not be stored with products which exhale strong aromas,
and the danger of contamination is lessened if the fruit can be cooled
down ina pure room before it is placed with other products in the
permanent compartment provided for it. For the same reason the
winter fruits should be stored in rooms in which the air is kept pure,
and preferably in compartments assigned to a single fruit.

The experiments furnish no evidence that the quality deteriorates
more rapidly as the temperature is lowered. On the contrary, all of
the experience so far indicates that the delicate flavors of the pear,
apple, and peach are retained longer in a temperature that approaches
the freezing point than in any higher temperature.

THE BEHAVIOR OF THE FRUIT WHEN REMOVED FROM STORAGE.

There is a general impression that cold-storage fruit deteriorates
quickly after removal from the warehouse. ‘This opinion is based on
the experience of the fruit handler and the consumer, and in many
eases is well founded, but this rule is not applicable to all fruits in
ali seasons. The rapidity of deterioration depends principally on the
nature of the fruit, on its degree of maturity when it leaves the
warehouse, and on the temperature into which it is taken. A Bartlett
pear, which normally ripens quickly, will ripen and break down in a
few days after removal. If ripe or overmature when removed, it will
decay much more quickly, and in either condition its deterioration
will be hastened if the weather is unusually hot and humid. In the
practical management of this variety it is fundamentally important
that it be taken from storage while it is still firm and that it be kept

EXPERIMENTS IN PEAR STORAGE. OF

as cool as possible after withdrawal. It is probably true that all
fruits from storage that are handled in hot weather will deteriorate
quickly, but it appears to be equally true that similar fruits that have
not been in storage break down with nearly the same rapidity if they
are equally ripe. The late pears, which ripen more slowly, if with:
drawn in cool weather will remain firm for weeks when held in a cool
room after withdrawal. If overripe they break down much sooner,
and a hot room hastens decay in either case. The same principles
hold equally true with apples. The winter varieties, if firm, may be
taken to a cool room and will remain in good condition for weeks or
months and retain their most delicate qualities, but in the spring,
when the fruit is more mature and the weather warmer, they naturally
break down more rapidly.

In commercial practice fruits of all kinds are often left in the stor-
age house until they are overripe. The dealer holds the fruit fora
rise in price, and removes it, not because the price is more satisfac-
tory, but because a longer storage would result in serious deterioration.
If considerable of the fruit is decayed when withdrawn, the evidence
is conclusive that it has been stored too long. Fruit in this condition
normally decays in a short time, but the root of the trouble lies not in
the storage treatment, but rather in not having offered it for sale
while it was still firm. In the purchase of cold-storage fruit, if the -
consumer will exercise good judgment in the selection of sound stock
that is neither fully mature nor overripe, he will have little cause to
complain of its rapid deterioration.

SUMMARY.

A cold-storage warehouse is expected to furnish a uniform temper-
ature in all parts of the storage compartments throughout the season,
and to be managed in other respects so that an unusual loss in the
quality, color, or texture of the fruit may not.reasonably be attributed
to improper handling or neglect.

An unusual loss in storage fruit may be caused by improper matur-
ity, by delaying the storage after picking, by storing in an improper
temperature, or by the use of-an unsuitable package. The keeping
quality is influenced by the various conditions in which the fruit is
grown.

Pears should be picked before they are mature, either for storage
or for other purposes. The fruit should attain nearly full size, and
the stem should cleave easily from the tree when picked.

The fruit should be stored at the earliest possible time after picking.
A delay in storage may cause the fruit to ripen or to decay in the
storage house. The effect of the delay is most serious in hot weather
and with varieties that ripen quickly. (See Pls. I, II], and IV, fig. 1.)

22 COLD STORAGE OF THE PEAR AND PEACH.

The fruit should be stored in a temperature of about 32° F., unless |
the dealer desires to ripen the fruit slowly in storage, when a temper- |
ature of 86° or 40° F., or even higher, may be advisable. The fruit
keeps longest and retains its color and flavor better in the low tem- |
perature. It also stands up longer when removed. (See Pls. H, IV,
fig. 2, and V.)

The fruit should be stored in a package from which the heat will be |
quickly radiated. This is especially necessary in hot weather and with |
quick-ripening varieties like the Bartlett pear. For the late pears that —
are harvested and stored in cool weather it is notso important. Bart- |
letts may ripen in the center of a barrel before the fruit is cooled down. |
A box holding not more than 50 pounds isa desirable storage package, |
and it is not necessary to have it ventilated. The chief value of a
ventilated package lies in the rapidity with which the contents are |
cooled, but long exposure to the air of the storage room causes the |
fruit to wilt. -(See Pl. VI.) |

Ventilation is essential for large packages, especially if the fruit is
hot when stored and ripens quickly.

A wrapper prolongs the life of the fruit. It protects it from bruis-
ing, lessens the wilting and decay, and keeps it bright in color. A
double wrapper is more efficient than a single one, and a good combi-
nation consists of absorptive unprinted news paper next to the fruit,
with a more impervious paraflin wrapper outside. (See Pl. VII.)

The quality of a pear normally deteriorates as it passes maturity,
whether the fruit is in storage or not, or it is never fully developed if
the fruit is ripened on the tree. The quality of the quick-ripening
summer varieties deteriorates more rapidly than that of the later kinds.
Much of the loss in quality in the storage of pears may be attributed
to their overripeness. The quality is also injured by impure air in the |
storage rooms, and the warm summer pears will absorb more of the
odors than the late winter varieties. The fruit will absorb less if cool
when it enters the storage room. ‘The air of the storage room should
be kept sweet by proper ventilation.

The rapidity with which the fruit breaks down after removal depends
on the nature of the variety, the degree of maturity when withdrawn,
and the temperature into which it is taken. Summer varieties break
down normally more quickly than later kinds. The more mature the
fruit when withdrawn the quicker deterioration begins, and a high
temperature hastens deterioration. If taken from the storage house
in a firm condition to a cool temperature, the fruit will stand up as

(long as other pears in a similar degree of maturity that have not been
in storage.

It pays to store the best grades of fruit only. Fruit that is imper-
fect or bruised, or that has been handled badly in any respect, does not

_ keep well.

COLD STORAGE OF THE PEACH. 23

INFLUENCE OF COLD STORAGE ON THE PEACH INDUSTRY.

Cold storage has not materially influenced the development of the
American peach business, and it is not likely to do so to any extent in
the future. In the early days of peach growing the industry was
localized in sections like the Chesapeake Peninsula, New Jersey, and
Michigan. The use of the fruit in considerable quantities was then
limited to a few near-by markets and to a short time in July, August,
and September. Now peach growing is rapidly extending to all parts
of the country where the climatic conditions and the facilities for
transportation are favorable. The refrigerator-car service has brought
the peach belts and the distant markets close together, and whenever
the crop is general the New York or the Chicago trade may be sup-
plied almost continuously from May till late October with fruit from
Florida, Texas, Georgia, the Chesapeake Peninsula, New Jersey, the
Ozark Mountain region, Michigan, New England, California, West
Virginia, western Maryland, and other peach-growing sections.

The chief value of cold storage to the peach industry will probably
lie in the temporary storage of the fruit during an overstocked mar-
ket, when, however, there is a reasonable prospect of a better market
within two or three weeks. It might be useful also in filling the gaps
between the crops of different regions, especially when there are local

failures which prevent a continuous supply. It is not now profitable
to store the fruit for any length of time, nor under any circumstances
unless the condition of the fruit and the storage conditions are most
favorable. The life processes in the peach and the weather conditions
in which it is handled make it even more critical as a storage product
than the delicate Bartlett pear. In normal ripening it passes from
maturity to decay in a few hours in hot, humid weather. The aroma
and flavor are most delicate in character and are easily injured or lost,
and the influence of any mismanagement of the fruit in the orchard,
in transit, or in the storage house is quickly detected by the consumer.

PRACTICAL DIFFICULTIES IN PEACH STORAGE.

Under the most favorable conditions known at present, peach stor-

-age is a hazardous business. Before the fruitis taken from the storage

house the flesh often turns brown in color, while the skin remains
bright and normal. Tf the flesh is natural in color and texture it fre-
quently discolors within a day or two after removal. There is a rapid
deterioration in the quality of stored peaches when the fruit is held
for any length of time, the delicate aroma and flavor giving way to an
insipid or even bitter taste. Sometimes the flesh dries out, or under
other conditions it may become ‘‘ pasty.” Dealers in storage peaches
frequentiy sell them in a bright, firm condition, and shortly after-
wards the purchasers complain of the dark and worthless quality of

24 COLD STORAGE OF THE PEAR AND PEACH.

the flesh. It has often been noticed that fruit in the various packages
in the same room does not keep equally well, some of it ripening and
even softening while the fruit in other packages is still firm. In fact,
the difficulties are so numerous that few houses attempt to store the
fruit. | ,

It has been the aim in the cold-storage investigations of the Depart-_
ment of Agriculture to determine, as far as possible, the cause of the
peach-storage troubles and to indicate the conditions under which the
business may be more successfully developed. |

OUTLINE OF EXPERIMENTS IN PEACH STORAGE.

The investigations have been conducted in the cold-storage depart-
ment of the Reading Terminal Market in Philadelphia, Pa., with —
Elberta peaches from the Hale Orchard Company, Fort Valley, Ga., |
and in the warehouse of the Hartford Cold Storage Company, Hart- |
ford, Conn., with Elberta and several other varieties grown by J. H.
Hale at South Glastonbury, Conn.

In Georgia the fruit was packed in the Georgia peach carriers, left
unwrapped, and divided into two lots, one representing fruit that was
nearly full grown, well colored, and hard; the other, highly colored
fruit, closely approaching but not yet mellow. Three duplicate ship-
ments were forwarded at different times in the two bottom layers of
refrigerator cars, and in each shipment part of the fruit was placed in
the car within three or four hours after it was picked, and an equal
quantity delayed in a packing shed from ten to fifteen hours during
the day before it was loaded. Equal quantities of each series were
stored in temperatures of 32°, 36°, and 40° F. The transfer from the
refrigerator car to the storage house was made by wagon at night, the
interval between the car and storage varying from two to five hours.

‘In Connecticut the fruit represented two degrees of maturity, simi-
lar to the Georgia shipments, except that the most mature fruit was ©
mellow when stored. This fruit was grown at an.elevation of 450 feet —
on trees six years old. It was medium in size, firm, highly colored, |
and of excellent shipping quality. Equal quantities were wrapped in_
California fruit paper and left unwrapped, and packed in the Connec- |
ticut half-bushel basket, in Georgia carriers, and in flat, 20-pound—
boxes, holding two layers of fruit. The peaches were forwarded by —
trolley to the storage house, which was reached in two hours after the
fruit left the packing shed. Duplicate lots of all the series were stored —

7 in temperatures of 32°, 36°, and 40° F. |

GENERAL STATEMENT OF RESULTS.

The general outcome of the experiments, both with the Georgia and_
the Connecticut fruit, is similar and may be summed up as follows: |
The fruit that was highly colored and firm when it entered the stor-_
age house kept in prime commercial condition for two to three weeks”

EXPERIMENTS IN PEACH STORAGE. 25

in a temperature of 32° F. The quality was retained and the fruit
stood up two or three days after removal from the storage house, the
length of its durability depending on the condition of the weather
when it was removed. After three weeks in storage the quality of
the fruit deteriorated, though the peaches continued firm and bright
in appearance for a month, and retained the normal color of the flesh
two or three days after removal. If the fruit was mellow when it
entered the storage house it deteriorated more quickly, both while in
storage and after withdrawal. If unripe it shriveled considerably.

In a temperature of 40° F. the ripening processes progressed rap-
idly, and the flesh began to turn brown in color after a week or ten
days in storage. The fruit also deteriorated much more quickly after
removal, as it was already nearer the end of its life history. It began
to lose in quality at the end of a week.

In a temperature of 36° FE. the fruit ripened more rapidly than in
32°, and more slowly than in 40° F. It reached its profitable commer-
cial limit in ten days to two weeks, when the quality began to dete-
riorate, and after this period the flesh began to discolor. (See Pl. I,
frontispiece. 3

The fruit kept well in all of the packages in a temperature of 32° F.
for about two weeks, after which that in the open baskets and in the
Georgia carriers began to show wilting. In the 20-pound boxes, in
which the circulation of air is restricted, the fruit remained firm
throughout the storage season.

It is necessary that the fruit be packed firmly to prevent bruising
in transit, but if the peaches pressed against each other unduly it was
found that the compressed parts of the flesh discolored after a week in
storage. A wrapper proved a grea‘ protection against this trouble,
especially in the baskets of the Georgia peach carrier, and in all of the
packages the wrapped fruit retained its firmness and brightness for a
longer time than that left without wrappers.

The fruit should be removed from storage while it is still firm
and bright. The peach normally deteriorates quickly after it reaches
maturity, and the rapidity of deterioration is influenced by the nature
of the variety, by the degree of ripeness when removed, and by the
temperature into which it is taken. A quick ripening sort, like
Champion, is more active biologically and chemically than the Elberta
variety, and the warmer the temperature in which either is placed
the sooner decomposition is accomplished. It is advisable therefore
to remove the fruit while firm and keep it in the coolest possible
temperature.

The peaches in the top of a refrigerator car that has been several
days in transit in hot weather are sometimes overripe and need to be
sold as soon as the market is reached, while at the same time the fruit
in the bottom layers may still be firm. The rapidity with which the

26073—No. 40—03——3

26 COLD STORAGE OF THE PEAR AND PEACH.

fruit cools down in the car depends on the care with which the car is
iced, and on the temperature at which the fruit enters the car. Fruit
that is loaded in the middle of a hot day and that has been picked ina
heated condition may be 20 or more degrees warmer than fruit picked
and loaded in the cool of the morning. Such warm fruit ripens much
more rapidly, consumes more ice in cooling down, and takes longer
to reach a low temperature. When the temperature in the top of the
car is higher than that of the lower part the ripening of the upper
layers of fruit will be hastened. If the fruit is destined for cold
storage, these upper layers, if more mature, should be piled sepa-
rately, and sold as soon as their condition warrants it. Under these
conditions if the fruit from this position is mixed in with the rest
of the load it may begin to deteriorate before the remainder of the
fruit shows mellowing.

The general principles outlined in former pages for the handling of
the Bartlett pear apply to the storage of the peach, except that the latter
fruit is more delicate and the ripening processes are even more rapid.
Every condition, therefore, surrounding the peach in the orchard, in
transit, in the storage house, and at withdrawal must be most favor-
able. The fruit must be well-grown and well-colored but firm when
picked. The packing must be done with care to prevent bruising.
If the fruit is to be transported in refrigerator cars, it should be
loaded soon after picking, and preferably before it loses the cool night
temperature. The peaches should be transferred from the cars to
the storage house, or from the orchard to the storage house if the
latter is near the orchard, in the quickest possible time. The air of
the storage room should be kept sweet and pure. The fruit should
always be removed to the coolest possible temperature, usually at the
end of two weeks, while it is still firm, and it should be placed in the
consumer’s hands at once. |

If the fruit is overripe when picked, or becomes meliow from
unfavorable handling before it enters the storage house, it is already
in a critical condition and may be expected to deteriorate quickly.

If the conditions outlined are observed in the handling of the peach,
it is possible to store it temporarily with favorable results.

x

DESCRIPTION OF PLATES.

PuatTE I. (Frontispiece.) Average condition of Georgia Elberta peaches two weeks
in storage aiter forty-eight hours’ withdrawal to a warm room. The upper
specimen represents the average condition of fruit stored in a temperature of
36° F. The lower specimen represents the average condition of the fruit stored
in 382° F. The lower temperature gave better results in every respect. (Natural
size. )

Puate Il. Average condition of Maryland Kieffer pears, March, 1902. This fruit
was picked from young trees on October 21, 1901, and was stored the following
day in a temperature of 32° F. Under these conditions the fruit kept well until
late in the spring. (Reduced one-fifth. )

Puiate III. Average condition of Maryland Kieffer pears on January 15,1902. This
fruit was picked from young trees October 21, 1901, and stored in a firm condi-
tion ten days later in a temperature of 32° F. The delay in the storage caused
the fruit to decay from the core outward. (Reduced one-fifth. )

Puate IV. Fig. 1 shows the influence of immediate and delayed storage on Mary-
land Kieffer pears. The fruit in the box at the right represents the average con-
dition of pears picked October 21, 1901, stored October 22, and withdrawn March
3, 1902. Storage temperature 32° F. The fruit was wrapped in parchment
paper. It was in prime commercial condition when withdrawn from storage.
The fruit in the box at the left represents the average condition of pears picked
from the same trees at the same time. It was stored in the same temperature
ten days later and withdrawn March 3, 1902. All of the fruit had decayed.
Fig. 2 shows the influence of 35° and 32° F. storage temperature on the keeping
of Kieffer pears. The fruit in both packages was picked October 21, 1901, and
stored October 22, 1901. The package at the left represents the average con-
dition of the fruit when withdrawn March 3, 1902, from a temperature of 36° F.
Ail of the pears were soft and discolored, and some of them decayed. The fruit
in the package at the right, kept in a temperature of 32° F., was bright yellow,
firm, and in prime commercial condition.

Pirate V. Average condition of Maryland Kieffer pears March 3, 1902. Picked
October 21, 1901; stored October 22, 1901. Temperature 36° F. In this tem-
perature the fruit did not keep well after December 1. (Reduced one-fifth. )

Prarre VI. The upper figure shows the average condition of western New York Bart-
lett pears in the center of a barrel one week after being placed in storage. In
this position the fruit cools more slowly than that near the staves or ends and
it therefore ripens considerably before the temperature is reduced. The lower
figure shows the average condition of the pears one week after storing at top and
bottom and next to the staves ef the same barrel. In these positions the fruit
cools quickly and the ripening processes are retarded. For quick ripening fruits
that are handled in hot weather small packages are preferable. (Natural size.)

Piate VII. Illustration of the influence of wrappers on the keeping of the Kieffer
pear. This fruit was picked October 21, 1901, stored October 22, 1901, in a tem-
perature of 32° F., and withdrawn January 20, 1902. Nearly 50 per cent of the
unwrapped fruit was decayed, while there was no loss in the fruit wrapped in
news paper or in parchment paper (lowest figure).

28

O

Bul. 40, Bureau of Plant Industry, U. S. Dept. of Agriculture. PLATE Il.

KIEFFER PEAR, MARCH, 1902. (FRUIT PICKED OCTOBER 21, 1901, AND PLACED IN
STORAGE THE FOLLOWING DAY AT A TEMPERATURE OF 32° F.) REDUCED ONE-FIFTH.

ee ae

ae

Bul. 40, Buréau of Plant Industry, U. S. Dept. of Agriculture. PLATE III.

KIEFFER PEAR, JANUARY, 1902. (FRUIT PICKED OcToBER 21, 1901, AND PLACED IN
STORAGE TEN DAYS LATER AT A TEMPERATURE OF 32° F.) REDUCED ONE-FIFTH.

Bul. 40, Bureau of Plant Industry, U. S. Dept. of Agriculture.

PLATE IV.

FiG. 1.—WRAPPED KIEFFER PEARS, REMOVED FROM COLD STORAGE (32° F.) ON
MARCH 3, 1902.

Fruit in both boxes picked October 21, 1901, that on the right being placed in storage on the
| following day, while that on the left was not stored for ten days.

Fic. 2.-WRAPPED KIEFFER PEARS, REMOVED FROM COLD STORAGE (36° aND 32° =)
ON MARCH 3, 1902.

Fruit in both boxes picked October 21, 1901, and stored on the followin
at a temperature of 32° and that on the left at 36° F.

g day, that on the right

”

on

=<

t-

Bul. go, Bureau of Plant Industry, U. S. Dept. of Agriculture. PLATE V

KIEFFER PEARS, MARCH, 1902. (FRUIT PICKED OcToBER 21, 1901, AND STORED
ON THE FOLLOWING DAY AT A TEMPERATURE OF 36° F.) REDUCED ONE-FIFTH.

Bul. 40, Bureau of Flant Industry, U. S. Dept. of Agriculture, REATGEOV:

BARTLETT REARS, ONE WEEK AFTER BEING PLACED IN COLD STORAGE. (THE UPPER
FIGURE SHOWS THE AVERAGE CONDITION OF THE FRUIT IN CENTER OF BARREL; THE
LOWER FIGURE THAT NEAR THE OUTSIDE OF THE BARREL.) NATURAL SIZE

Bul. 40, Bureau of Plant Industry, U. S. Dept. of Agriculture. PLATE VII.

KIEFFER PEARS, REMOVED FROM COLD STORAGE ON JANUARY 20, 1902.

Fruit picked October 21, 1901, and placed in storage on the following day. Nearly
of the unwrapped fruit decayed, while that in parchment wrappers (
unprinted newspaper kept in perfect condition,

00 per cent
lowest figure) and in