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we Circular No. 659 L t <o— , t home . _ y

Handling Apples

from Tree to Table

By

D. F. FISHER
Principal Horticulturist
Division of Fruit and Vegetable Crops and Diseases
Bureau of Plant Industry

POOPED ABA ALLLALALAGL AGL ALLL AAG LIAL LALO IAL

For sale by the Superintendent of Documents, Washington, D. C. Price 15 cents

UNITED STATES DEPARTMENT OF AGRICULTURE

WASHINGTON, D. C., AUGUST 1942

Circular No. 659
August 1942 * Washington, D.C.

UNITED STATES DEPARTMENT OF AGRICULTURE

Handling Apples from Tree to Table

By D. F. FisHeEr, principal horticulturist, Division of Fruit and Vegetable Crops
and Diseases, Bureau of Plant Industry

CONTENTS
Page Page
IMprodu Chon esa eee nee eee eae 1 | Factors affecting condition during storage—
The grower’s responsibility__----------------- 2 Continued.
Wihen! to:pick-apples===2== = 222 s222e5 22 2 EIT ETS; GIS CASCS eee ear een ee 14
Criteniaohmatunty.=————— 3 Bruising and other mechanical injuries _ 16
WH enstowpaAcke ap plES=ee ae eens 5 Physiological diseases_____________________ 20
Factors affecting condition during storage _--- (da| AE TreCtSto packaran caesarean tee eee ees 24
Matunityeatinarnvest<2-- = - ee. seas See 7 Prepackaging for the consumer_______ ____ 31
Storage temperatuneses 225 eae 8 | The shipper’s responsibility__________________ 31
Gasistonac ee eee Sie ae ee 11 | The dealer’s responsibility___________________- 34
Atmospheric humidity________-_-__------- 12 | The industry’s responsibility________________- 38
Storage with other products___----------- 14S PIGICERALUINeXCILC Cet roe tne ee ee nines 29
INTRODUCTION

The condition of apples offered for sale by grocers and other retail
vendors 1s sometimes disappointing to the purchaser. To the extent
that the demand for apples is influenced thereby it affects the market
price of the fruit and the returns to the grower. The factors of con-
dition that are most important are the stage of ripeness of the fruit
and its freedom from decay, bruising, and other injuries.

Growers who invest a season’s work in pruning, fertilizing, spray-
ing, and cultivating their orchards with all the care and expense neces-
sary to produce a clean crop of high-quality fruit cannot help being
disturbed by the poor condition of. apples offered by retailers, which
also constitutes one of the greatest handicaps to success of organiza-
tions established by the apple industry to advertise and otherwise
promote the sale and use of apples.

Growers oftentimes are inclined to place the blame for the lack
of quality in the apples offered in grocery stores and other outlets on
the retailers and other intermediate factors in the merchandising
chain. They feel that the retailers and other handlers of the fruit
are not “apple-minded,” that to them apples are just so much perish-
able merchandise which must be handled and priced according to the
risk attached; that, in the absence of knowledge as to how the risks
can be minimized, the retail price of the fruit is often pyramided to a
point at which sales are retarded and the whole industry suffers cor-
respondingly, and that, consequently, customers are often unable to buy
the kind of apples that they would like and turn to competing fruits.

Market men, on the other hand, hold that fr equently the fruit when
received has already deteriorated so much that its value is greatly re-
duced and the hazards of further deterioration while in process of sale

467795° —_42——_1 a

2, CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

are greatly increased. Most retailers are no more interested in apples
than in any other commodity that will yield the same profit; so, if
there are unusual risks in handling apples, this fruit naturally will not
receive the consideration that it otherwise would.

It is the purpose of this circular to present in concise, nontechnical
form the available information on the way in which apples should be
handled from the time of harvest so that they will reach the ultimate
consumer in prime condition, and to give the reasons for the various
recommendations. This information is of special importance under
existing war conditions when provision of adequate supplies of all
kinds of foods is being emphasized. It would be of little use to pro-
duce greatly enlarged crops if they are to be allowed to deteriorate
on the way to market or in storage. Therefore, while carrying out a
program for increased production of essential foods, emphasis should
be given to the avoidance of waste and the proper conservation of the
crops produced. Furthermore, proper handling of apples during har-
vesting and packing, and the use of proper storage methods before
shipment, will lessen the load on transportation facilities already
heavily taxed by war traffic, by avoiding the hauling of fruit to market
which should be left on the farm or taken to nearby byproduct plants.

THE GROWER’S RESPONSIBILITY

In the business of placing good-quality fruit before the consumer
it is the responsibility of the producer to grow a crop of good apples.
Many growers are, however, more interested in growing a good crop
of apples. The difference between the two objectives may seem slight,
but in the general problem of giving the public the kind of apples
that will stimulate demand, it is significant. It is axiomatic that the
orchard must be properly pruned, sprayed, and cultivated to produce
a profitable crop. Every successful orchardist, although alert for
new ideas in apple culture, is already familiar with good cultural
practices and is producing a certain proportion of good apples. Pro-
gressive growers constantly strive to increase the proportion of good
apples as well as to increase the size of the crop.

WHEN TO Pick APPLES

One of the principal causes of the poor condition of apples as they
finally reach the consumer is the failure to pick them at the proper
stage of maturity. If apples are picked too soon, they are more
likely to shrivel, will fail to develop good eating quality, and are
very susceptible to certain functional diseases that develop later, par-
ticularly bitter pit and scald. If they are not picked soon enough,
they will not stand up well in storage and are subject to other func-
tional diseases that often cause serious losses in storage, especially
soft scald and internal break-down. The reason for these failures
is that the apple is a living organism with a more or less definite
potential span of life. If it “lives too fast” either before or after
picking, its vitality is exhausted prematurely, and the time it remains
in good eating condition is shortened proportionately.

While the apple is attached to the tree, it is part of the tree and is
influenced by any factors that affect the growth of the tree. When
the tree suffers from drought, for example, the apple responds by

HANDLING APPLES FROM TREE TO TABLE 3

slowing down its rate of growth; and when the tree is so stimulated
that it makes abnormally fast growth, the fruit grows vigorously and
may become overgrown and punky. As the fruit. grows it accumulates
the various constituents which finally characterize a mature apple.
Not all of these constituents are accumulated at the same rate, and only
at maturity is the final desirable balance reached. As the apple grows,
the fleshy part becomes essentially a reservoir for the materials upon
which its potential storage hfe depends. These are chiefly carbo-
hydrates, malic acid, water, small amounts of aromatic materials
highly important m determining flavor, and vitamins and minerals
important in determining dietetic value. As the apple approaches
maturity, it continues to increase in size but loses acidity and increases
in sweetness. The carbohydrates in the flesh of a green or immature
apple are largely starch, which is almost all converted into sugar as
the fruit ripens. Ripening may occur either before or after harvest
and is accompanied by a softening of the flesh and an increase in
juiciness and aroma.

Some of the sugar, a relatively small proportion, converted from
starch in the apple is used in respiration, being broken down to carbon
dioxide and water, which are given off to the atmosphere. The acidity
is, however, reduced to a much greater extent during ripening than
is the sugar; hence, the flavor becomes progressively more characterless
and less desirable as the apple is held beyond its normal storage season.
Everyone knows that if an apple is left on the tree or held in storage
too long it eventually becomes mealy, flavorless, and soft. When the
life processes of the fruit are carried so far that pectic materials finally
dissolve out of the cell walls, permitting the cells to separate easily,
the mealiness that characterizes the texture of overripe apples is pro-
duced. What remains at the end is an apple in the last stages of senil-
ity, entirely unsuitable for market and undesirable for either culinary
or dessert use. Therefore, while it is essential to allow the fruit to
become mature before harvest in order to develop best quality, the
ripening for the most part should occur after harvest in order to insure
good storage and market quality.

CRITERIA OF MATURITY

The most generally used criteria of maturity are ease of separa-
tion of the fruit from the spur, ground color, and firmness of the fruit
(9)... However, none of these is entirely dependable under all
conditions.

EASE OF SEPARATION FROM THE SPUR

When an apple is ready to pick, it can be separated from the spur
without breaking the stem merely by lifting it in the hand with or
without a slight rotating movement. Since the attachment of the
fruit to the spur is like a hinge, picking should be an unhinging
process. Instead of picking the fruit in this way inexperienced or
careless pickers often pull the fruit from its attachment. This usually
results in breaking the spurs, which cuts down the bearing surface and
reduces succeeding crops, or in pulling out the stem of the apple and
tearing the flesh, which open the way for decay to start.

1 Italic numbers in parentheses refer to Literature Cited, p. 39.

4. CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

Under some conditions apples may start to drop before they are
properly mature. In such cases, of course, they are harvested al-
though they may not be sufficiently mature to develop the best quality
after. ripening. Recently there has been an increase in the use of the
so-called hormone sprays, such as naphthalene acetic acid, to prevent
fruit drop (4). Use of a preharvest hormone spray invalidates the
ease of separation from the spur as a criterion of maturity. As a
result of this treatment the fruit can be retained on the tree longer
to become more mature and riper before harvest than if such sprays
are not used.

GROUND COLOR

The blush or red color of an apple is not a reliable index of maturity,
but with many varieties the ground color is. The quality of a red
apple can ordinarily be judged by the proportion of red to green;
the more red, the better the eating quality. But the ground color is
important in determining maturity, or when the apple should be
picked. As most varieties of apples become mature, the ground
color changes from a green very much lke that of the leaves to a
hghter Slate and eventually to ‘yellowish. With most varieties the
time to pick is when the first signs of yellowing begin to appear, and
ordinarily there is no difficulty in determining when this time comes.
However, this is not always true with some varieties (Grimes Golden,
Jonathan, and Yellow Newtown as grown under certain conditions),
particularly with the various red bud sports that have been developed
in recent years. The latter usually become fully red before they are
mature, with no uncovered ground color left for observation. The
result has been that they have often been picked too soon and have
suffered in popular esteem because they are judged to have poorer
quality than the parent variety. Ground color cannot therefore ordi-
narily be used as an index of maturity in the red bud sports. How-
ever, it has been found that the red bud sports do not differ materially
in their season from the varieties from which they have been selected.
and it is therefore practicable to use the ground color of the parent
varieties for determining when to pick apples of the sports.

PERIOD FROM BLOSSOMING TO MATURITY

The problem of determining proper maturity has been of the most
concern to growers of the various red bud sports of the Delicious, par-
ticularly in 1 the Pacific Northwest, where many plantings of the origi-
nal Delicious variety have been entirely replaced by Starking, Rich-
ared, or other red bud sports. When the difficulty in determining ma-
turity of these all-red varieties by customary indexes became : apparent,
the United States Department of Agriculture began an investigation
to determine whether the length of time that must. elapse from time of
blossoming to optimum maturity for harvest might be used as sug-
gested by Magness and others (10). The investigation has now been
in progress for several years. The results have shown that for satis-
factory eating and good storage quality at least 145 days must elapse
from the time of the first petal “fall until the time of beginning harvest.
Limited observations in the section about W ashington, D. “C. have
indicated the same thing. Therefore, if growers in these sections will
observe the date when petals begin to fall from the earliest blossoms,

HANDLING APPLES FROM TREE TO TABLE 5

they can, by adding 145 days, immediately tell when to plan on start-
ing to pick the Delicious or any of its red bud sports. The study 1s now
being extended to other varieties and other sections, and it is possible
that eventually recommendations as to definite lengths of growing
seasons can be made for all varieties.

FIRMNESS AS DETERMINED BY PRESSURE TEST

Firmness, as indicated by the pressure test, is another index of ma-
turity that can be used. To date the pressure test has been used ex-
perimentally more than in a practical way. However, in conjunction
with other criteria already mentioned, it is an additional useful index
of maturity. Used independently of other criteria, it is of value
chiefly in determining when apples are becoming overmature and too
soft for storage rather than when picking should begin.

As apples approach maturity, they become progressively less resist-
ant to pressure, a characteristic which makes it possible to utilize me-
chanical means of measuring the rate of softening. Several types of
pressure testers have been evolved. The one most commonly employed
is that developed by Magness and Taylor (77), which measures the
pressure required to force a plunger seven-sixteenths of an inch in di-
ameter into the flesh of the apple to a distance of five-sixteenths of an
inch after paring off the skin. Haller (4) has presented the results of
a long series of investigations on the use of the pressure test on apples
and various other fruits and has reviewed the findings of many other
workers. Pressure-test records have been transposed into the ordinar-
ily accepted commercial designations of “hard.” “firm,” “firm ripe,”
and “ripe” by Haller, Lutz, and Mallison (6). The publications re-
ferred to should be consulted for detailed information as to the appli-
cation and limitations of the pressure test.

WiEN TO PACK-APPLES

Ideally, apples should be packed and stored or shipped immediately
after being picked. Danger of blue mold infection is less if this can
be done because the danger of injuring the apples during the packing
operations is much less if the fruit is hard than if it has begun to
soften. Scald can also be controlled much more effectively if oiled
paper is applied soon after the apples are harvested. Unless the oiled
paper is apphed within a month, or 6 weeks at the most, it is in-
effective in controlling scald. Another advantage of prompt packing
is that it gives an opportunity to sort out the culls. which not only
may be sources of infection by rot organisms but which also take up
valuable storage space that may be needed for marketable fruit.

Practically, however, a large percentage of the crop is often kept
from a few days to several months before it is packed for market.
Sometimes this delay is due to lack of sufficient packing facilities to
take care of the fruit as fast as it is picked, and sometimes packing is
intentionally postponed or spread out. If the apples are particularly
susceptible to bitter pit, it may be advisable to delay packing for a
month or 6 weeks to give the disease a chance to become manifest so
that affected apples can be sorted out. When the delay is for more
than a few days, the fruit is ordinarily placed in storage and packed
at the convenience of the owner. Although this has some advantages,

6 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

especially from the standpoint of spreading labor, these are out-
weighed by the disadvantages. When packing houses are congested
and cold-storage space is not available, it is ordinarily preferable to
let the picked fruit remain in the orchard in the shade of the trees;
the boxes should be spaced so that air can circulate freely about them,
and the stacks should be covered so as to protect the fruit from direct
sunlight and rain (fig. 1, 4). The apples will ripen less rapidly than

if stacked in the open in unprotected large piles at the packing house
as is sometimes done (fig. 2).

B

Figure 1.—A, Boxes of apples in the shade of a tree in an orchard. Note that
the boxes are covered to protect the fruit from direct sunlight-and rain and
that the air can circulate freely about them. B, Hauling cull apples from the

packing house. Frequent disposal of culls will reduce sources of infection by
decay fungi.

HANDLING APPLES FROM TREE TO TABLE 7

Figure 2.—Holding apples in large compact stacks outside of a packing house
is not recommended. In such piles, unprotected from sunlight and rain,
ripening is accelerated.

FACTORS AFFECTING CONDITION DURING STORAGE

The sequence of changes in the harvested fruit is much the same
as In apples that are allowed to remain on the tree until they become
overripe, mealy, and insipid; that is, even fruit harvested at the
proper stage of maturity will eventually become mealy and flavorless
if held too long or under improper storage conditions. In fact, unless
the fruit is placed in cold storage promptly, the approach of senility
is more rapid after the fruit is picked than when it 1s left on the tree.
The length of time that apples can be held in satisfactory condition
in storage depends on three factors: (1) Maturity at harvest, (2) the
storage temperature, and (3) the presence of diseases.

Maturity AT HARVEST

Apples picked before they are sufficiently mature generally remain
sour and astringent even after they have ripened and, except for the
red bud sports, are poorly colored. They have a marked tendency to
wilt or shrivel and are susceptible to scald and bitter pit during
storage.

The apples most often picked before they reach the proper stage
of maturity are the solid-color varieties, such as the Grimes Golden
and Yellow Newtown among the green or yellow kinds and the red
bud sports of the Delicious, as alre eady mentioned. When picked at
the proper stage of maturity, all these rate among the best for dessert
quality ; but when picked too soon, they are suitable only for culinary
use, and the Delicious is not particularly good even for that.

When the weather remains warm at harvesttime, particularly at
night, some varieties of red apples are slow to color and there is a

8 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

tendency on the part of growers to delay picking until the apples do
color, with attendant danger of loss from dropping and of the fruit’s
becoming too mature for storage. Because this is particularly true
of Jonathan, Delicious, and Rome Beauty, red bud sports of these
varieties have been eagerly sought and largely substituted wherever
possible. Many large plantings of the original varieties will donbt-
less remain in heavy production, however, and in such cases there
will continue to be problems of color, dropping, and overmaturity.
Use of hormone sprays, which prevent apples from dropping, meets
the problem of slow coloring only in part, since there is danger that
apples thus held on the tree to color may become too far advanced in
maturity or may be fully ripe at time of picking. Overmature apples
are particularly susceptible to water core, soft scald, internal break-
down, and Jonathan spot and are more subject to stem punctures,
bruising, and other mechanical injuries through which blue mold
infection takes place. Blue mold infection through lenticels is also
more likely to occur in overmature apples than in those picked at
proper maturity.

STORAGE [TEMPERATURE

The life processes of apples tliat have to be considered in the suc-
cesstul storage of the fruit after harvest are essentially chemical, and,
as with other chemical processes, the rate at which they proceed de-
pends largely upon the temperature at which they can be carried out;
1. e., upon the temperature of the apples. Apples freeze at. a tempera-
ture of about 28.5° F. (77) ; hence, it is necessary to keep them above
this temperature. In practice, storage temperatures of 30° to 32° have
been found most satisfactory (75).

Magness and others (77) found that the rate of respiration largely
governs the rate of ripening and softening of apples in storage. They
found that at 40° F. this rate is approximately twice as rapid as at 32°,
at 50° it is almost double that at 40°, and at 70° it 1s about twice as fast
as at 50°. At 30°, on the other hand, 25 percent longer time is required
for apples to ripen than at 32°. From these results, therefore, the
extreme importance of quickly cooling apples to the minimum safe
temperature for storage is readily apparent, because the apples will
ripen as much in 1 day at 70° as they will in 10 days at 30°. Holding
apples at 70° for only 8 days after harvest thus will cut off about a
month of their potential storage life at 30°. If 30° storage is not im-
mediately available, every opportunity should be used to cool the fruit,
such as stacking it in the shade and providing good ventilation, espe-
clally at night (fig. 1, 4). The same principle applies after storage.
It is therefore inadvisable to remove from cold storage at one time more
apples than can be used or marketed before they deteriorate seriously.
It must also be remembered that after storage the span of life remain-
ing for the fruit is much shortened, and as the end point is uncertain,
the gamble in holding at warm temperatures is much greater.

Cooling the fruit means the transfer of heat from the fruit to the
air surrounding the fruit. The effectiveness of the cooling depends on
the difference between the temperature of the air and that of the fruit
and the rate at which the air moves over the fruit. In common stor-

HANDLING APPLES FROM TREE TO TABLE 9

age, cooling is accomplished by transferring heat from the fruit to the
outside air. A good ventilating system intelligently operated is neces-
sary to make this method efficient ; the vents should be opened when the
outside air temperature is lower than that of the fruit and closed when
conditions are reversed. In cold storage the heat is transferred from
the air surrounding the fruit to refrigerated pipes or other artificially
cooled surfaces and eventually is transferred to the outside air by the
refrigeration system.

The cooling of the fruit ordinarily is not a rapid process, nor is its
ripening checked instantaneously when it is placed in cold storage.
Time is needed to remove the heat from the fruit because the rate of
cooling is affected not only by the temperature but also by the type
of package, the method of packing, the quantity of warm fruit placed
in the room, the manner in which the packages are stacked, and the
rate of air circulation around the fruit. Table 1 presents results of
tests conducted at the cold-storage laboratory, United States Horticul-
tural Station, Beltsville, Md., to determine the influence of the type
of package on the rate of cooling. In this series of tests the temperature
records were taken at the core of an apple at the center of each of the
various packages. The packages were not stacked and, being freely
exposed on all sides, cooled faster than they would under commercial
storage.

Tasite 1.—Influence of method of packing and storing apples in unstacked
individual packages on their rate of cooling at 32° F. in still air

Temperature at core of apple in center of
package—
Package Packing material

When | After | After | After | After | After
stored |12 hours|18 hours|72 hours! 7 days | 10 days

NE Te oe OF OOF oF
Bushel basket______ IN ON GS ee ee ee, a 63 42 D2 Beg Pe scneaa esl aly oe = ae ene
OS Ses ra | Liner, cushion, shredded oiled 70 59 44.5 41} 33.5 32.5

| __ paper |

Barre ese ee teaNone === 2 =. aa eee eae 66 64 5 Oban 55: | -41 36
Standard box______ Liner, cushion, oiled wraps_____- 71 Gia |eaO0- | 54 41.5 37
114-bushel eastern | Liner, cushion, shredded oiled | 66 Goel pee 6 lecen| 59 54 44

crate. paper.

The results show that the use of liners, cushions, and paper for
packing slows up the rate of cooling. Apples in an open bushel basket
just as they came from the orchard, without liners, wraps, or shredded
oiled paper, cooled from 63° F. to 32° in 18 hours, whereas fruit
packed in lined baskets with a pad under the lid and shredded oiled
paper well distributed throughout required about 10 days to cool from
70° to 32.5°. The relative thickness of the containers doubtless had
an effect on the rate of cooling, but the size of the package or the
mass of fruit enclosed and the tightness of closure apparently were
important factors also as can be noted by comparing the results for
apples packed in the barrel with those in the open bushel basket; it
took only 18 hours to cool the fruit in the middle of the bushel basket
from 63° to 32°, but it required 10 days to cool that in the middle
of the 3-bushel barrel from 66° to 36°. Similar results can also be

467795°—42 2

10 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

noted for the apples packed in the standard box and in the 114-bushel
eastern crate, the packing in both cases, however, including liners
and pads as well as oiled wraps or shredded oiled paper. The eastern
crate contained 20 percent more apples and was the tighter package,
and after 10 days the fruit in its center had cooled only 22°, while
that in the standard box had cooled 34°.

The results shown in table 1 should not be interpreted to mean
that use of pads, liners, and other packing material is undesirable
but rather that these materials insulate the fruit and increase the
requirement for refrigeration if properly packed apples are to be
cooled as quickly as is desirable.

In view of the results shown in table 1 the question arises as to
what would be the effect of lowering the temperature of the air below
32° F. on the rate of cooling. This is done in precooling, which is
the term apphed to the rapid lowering of the temperature of a com-
modity to any desired level. While apples are not commercially
precooled to the same extent as are peaches, pears, plums, and certain
other fruits, in many cases it would undoubtedly be beneficial to
precool them, Delicious in particular because it is so prone to become
mealy and overripe. Records of fruit temperatures, if taken in many
storages, would disclose that most of the fruit is not cooled to 32°
for several weeks after harvest. Meanwhile, the rate of ripening is
being arrested only in proportion to the rate of cooling. The slow
cooling is often due to lack of sufficient refrigerating capacity of the
cold-storage plant, but it may also be due to faulty stowage in the
room, particularly failure to leave space for air circulation through
the stacks and to spread out large receipts of warm fruit.

The greater the difference between the temperatures of the com-
modity and of the cooling medium and the more rapid the rate of
air movement the more rapid the rate of cooling will be. However,
as the temperature of the commodity approaches that of the cooling
medium the rate drops off. These effects are shown in figure 3, which
presents data obtained in another series of experiments conducted in
the United States Department of Agriculture cold-storage laboratory
at Beltsville, Md. The records were taken in the top layer of pack-
ages held at 32° F. and stowed as they would be in commercial prac-
tice. In the middle of the stacks the rate of cooling was slower be-

ae | | | | |
STILL AIR; LINER, PAD, AND SHREDDED OILED PAPER

ela =r | SO STILL AIR; WITHOUT LINER, PAD, OR SHREDDED OILED PAPER

Sali —-—- MOVING AIR; LINER, PAD, AND SHREDDED OILED PAPER

—--— MOVING AIR; WITHOUT LINER, PAD, OR SHREDDED OILED PAPER

ss.

TEMPERATURE (°F.)
oO
{e)

fe) 72 84 96 108 120 132 144 i56 168
ELAPSED TIME (HOURS)

FIGURE 3.—Rates of cooling of apples packed in bushel baskets and stored at
32° F. in still and in moving air. Velocity of the moving air was approxi-
mately 200 feet per minute. The thermometer was located in centermost
fruit in each container.

HANDLING APPLES FROM TREE TO TABLE Iba

cause the air could not circulate as freely as over the top of the stacks.
From figure 3 it will be seen that the apples cooled more in the first 12
hours than in the next 12 and that the rate of cooling fell off pro-
gressively thereafter as the temperature of the fruit approached that
of the air in the storage room. The insulating effect of the liners,
pads, and the shredded oiled paper ordinarily used is brought out in
these results as well as in those in table 1. The effect of air movement
in increasing the rate of cooling is also brought out clearly in figure 3.
When the rate of air movement was about 290 feet per minute, the
apples without packing material cooled to 32° in 36 hours, while in
still air.they required more than 96 hours to reach this temperature.
In the baskets with liners, pads, and shredded oiled paper similarly
packed apples required 57 hours in the air moving at 200 feet per
minute and more than 156 hours in still air.

Some people are afraid of pessible ill effects of cooling fruit too
quickly; they fear that it may produce some kind of “shock” from
the rapid change of temperature. No apprehension of such effects
is justified. The more rapidly fruit can be cooled to the proper
storage temperature, the more quickly will the deteriorating processes
of ripening be arrested, and the longer the fruit can be kept in good
condition,

Gas STORAGE

In England, some varieties of apples, particularly the leading culi-
nary variety, Bramley’s Seedling, will not endure ordinary cold stor-
age without developing low-temperature break-down. .'The same situ-
ation exists to a limited extent in certain parts of the United States,
particularly with Yellow Newtown apples grown in the Pajaro Valley,
Calif., and with McIntosh grown in New York State, in which brown
core may develop excessively during storage at 32° F. The so-called
gas-storage method was developed by Kidd and West (7) in England
to meet this problem. To utilize this method an airtight storage
chamber is required and the carbon dioxide produced in the respira-
tion of the apples is allowed to build up to the desired concentration
while the oxygen content of the storage air is reduced. ‘The tempera-
ture of the storage room is usually held at 40° to 45° ; so ordinarily some
refrigeration is required in addition to the gas treatment. Since
different varieties respond best to different ratios of carbon dioxide to
oxygen, different chambers may be required for different varieties. The
desired ratio is obtained either by pumping the storage air through
a lye solution to absorb the excess carbon dioxide or Dy ventilating
the chamber periodically to admit fresh air and build up the oxygen.
Since the vast bulk of the American apple crop can be held satis-
factorily in cold storage and most varieties are not benefited by the

gas treatment, it is not like ly that this method of storage will have
wide application i in this country because of the added cost and extra
work that it entails. However, for special situations it may be utilized
profitably despite the extra cost. Several gas storage rooms have
been put into operation in New York for the storage of McIntosh
apples in accordance with the recommendations of Smock and Van
Doren (/6).

12 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

ATMOSPHERIC HumuipIty

Keeping the apples from wilting and shriveling is as important as
keeping them from getting overripe and can be done by controlling
the humidity in the storage space. A certain amount of moisture is
continuously lost by the apples through the process of transpiration
(evaporation).

Although it can be cut down by reducing the temperature, it is par-
ticularly serious in apples which are not properly matured and on
which lenticels are not normally corked over and the wax coating is not
sufficiently developed. The natural barrier to loss through evapora-
tion is the waxy skin of the fruit. Any injury to the skin or the re-
moval of the wax, as in some washing processes, facilitates moisture
loss and increases the severity of wilting. Careful handling to avoid
bruising and injury of the skin and the use of proper washing processes
are important therefore in preventing excessive wilting or shrinkage
in storage as well as blue mold rot and other types of decay. The drier
the air the greater is the degree of wilting. The faster the air is moved
over the apples the more moisture will be removed from the fruit. The
extent to which this occurs in apples has not been determined exactly,
but in grapes Allen and Pentzer (/) found that doubling the air
movement increased moisture loss by about one-third and was equiva-
lent to about a 5-percent drop in relative humidity. If the relative
humidity of the storage is maintained at 85 percent or higher, which
is the approximate water content of apples, the “pull” on the fruit for
moisture or the evaporating power of the air will be slight and shrink-
age of the fruit will be correspondingly lessened. Observations in
commercial cold storage plants have shown that the relative humidity
in the apple storage rooms is frequently less than 85 percent, sometimes
as low as 70 percent.

To maintain desirable humidity conditions and to reduce chances of
wilting, it is always desirable to fill the storage rooms, thus reducing
as much as possible the ratio of air to fruit. In such cases, however, it
is essential to have a gentle air movement through and around the
stacked fruit to insure proper cooling. This is not a serious problem
when apples are packed in bushel baskets (fig. 4), but it 1s when boxes
or crates are used. In the latter event, the stacks should be spaced an
inch or two apart and laths or other dunnage strips should be used to
separate the boxes or crates in each stack. When a storage room is
completely filled with apples, the humidity will be almost automati-
cally adjusted at the desired level.

It is desirable to have sufficient coil surface in a cold-storage room
to provide the desired cooling without using excessively low tempera-
ture in the cooling medium. The greater the difference in temperature
between the cooling surface and the air of the storage room, the more
the air will be dried by the freezing out of moisture and the greater
will be the pull on the fruit with corresponding wilting effects. If
there is sufficient coil surface to permit use of the cooling medium at
not more than 7° or 8° F. below the desired temperature of the room,
the freezing out of the moisture from the air onto the coils will be
minimized.

HANDLING APPLES FROM TREE TO TABLE 183

Ficure 4.—Method of stacking bushel baskets of apples and staggering them by
placing each basket on the edges of those beneath to keep pressure away from
centers of lids. Stacking baskets as shown, instead of putting alternate baskets
upside down as is sometimes done, permits better air circulation. Permitting
the workmen to stand or walk on the baskets is not desirable.

It is difficult to raise the humidity in a cold-storage room kept within
the most desirable temperature range for apples, 30° to 32° F., because
the moisture is so quickly condensed and frozen. However, if it be-
comes necessary to raise the humidity, it can be done best by using a
humidifying apparatus that introduces steam into the air of the
storage room. A simple humidifier of this type can be made by plac-
ing a shallow pan on some strip heaters, operation of which is con-
trolled through a humidistat. An electric fan should be arranged to
blow over the surface of the water. The efficiency of the apparatus can
be increased somewhat if absorbent toweling is looped into the water
from a series of parallel supports placed 8 to 10 inches above the sur-
face of the water. In this arrangement the air current from the fan
should pass through the loops of the wicking. Adding moisture to
raise the humidity by any method must be regarded as only an expedi-
ent rather than as the most satisfactory method of controlling wilting
and shrinkage. All that can be accomplished by evaporating ‘moisture
into the storage air is to supply some of the moisture requirement of
the air rather than to permit it all to be taken from the apples. The

14 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

moisture requirement of the air cannot be satisfied so long as the tem-
perature of the cooling surfaces remains markedly lower than that of
the air.

STORAGE Wi1TH OTHER PropucTs

Apples absorb odors very readily, and it is therefore undesirable
to store them with other products that have pronounced odors. This is
particularly true of potatoes and other root crops, which often impart
an “earthy” flavor to apples. Since apples give off ethylene, a gas that
stimulates respiration and ripening, the potential keeping quality of
other products stored with apples may be adversely affected. This is
particularly true of cut flowers, which may be caused to shed their
petals or are otherwise injured by ethylene (78).

Funcus DIsEASES

There are many fungus diseases of apples that can cause serious
losses under certain conditions. Fortunately, however, most of these
are primarily orchard diseases and are controlled on the harvested
fruit by the sprays that good growers apply to control them in the
orchard. However, if they are present on the stored fruit, they
respond to storage temper atures about the same as do the physiological
processes of the fruit already discussed (p. 8). AII of them develop
rapidly and are most destructive at warm temperatures, whereas at
30° to 82° F. many will not develop at all, or at the most very slowly,
particularly if the apples are not ripe. The spores of most rot organ-
isms will not germinate at 30° to 32°, but if infection has already
occurred when apples reach this temperature, most of the rots will
persist during storage and the causal organism will resume growth
after the fruit is removed to a warm temperature. Detailed informa-
tion regarding the diseases of apples in storage can be found in United
States Department of Agriculture Miscellaneous Publication 168 (23)
and Farmers’ Bulletin 1160 (3). Discussion can be limited here to a
relatively few diseases that are especially influenced by harvesting,
handling, and storage operations; most of these are not due to fungi
but are functional or physiological in nature.

The storage disease responsible for most of the decay in apples
after harvest is blue mold rot. caused by the fungus Penicillium ex-
pansum Link. It is primarily a wound parasite and ordinarily re-
quires some kind of mechanical injury to infect an apple. This rot
is very soft and watery and has a pronounced musty odor. It gets its
name from the bluish masses of spores that appear on the surface of
affected areas (fig.5,A). This fungus is omnipresent wherever apples
are grown, and its spores are found in large numbers on the surfaces
of apples as they are picked and brought in for packing. Since the
fungus is ordinarily incapable of penetrating the sound, uninjured
skin of the apple, careful handling of the fruit at all times is a prime
requisite in preventing infection. Bruising and other mechanical
injuries lead to blue mold infection.

Although blue mold enters apples most often through mechanical
injuries, it sometimes enters thr ough open lenticels in the skin,
through the stem, especially when this is enlarged or fleshy and has

HANDLING APPLES FROM TREE TO TABLE es

Cc D

FIGURE 5.—A, Blue mold rot, which is soft and watery, has a pronounced musty
odor and frequently is covered with bluish masses or spores. B, Very slight
bruises, which show prominently on a peeled apple, the emphasizing need for
careful handling at all times to keep the apples from being bruised. C, Bit-
ter pit, which occurs as brownish spongy or corky spots or pits in the flesh just
under the skin and usually is most prevalent on the blossom end. JD, Jona-
than spot, a superficial skin disease that gives the apple a freckled appearance.

been broken or injured, and also through dead calyx lobes resulting
from spray Injury, washing injury, or other causes. Infection is more
likely to occur in ripe apples than in those which are still hard, and
also it is most likely to occur at points of contact with another fruit.
When apples are washed, the spores of decay organisms, especially
blue mold, accumulate in the washing solutions and infection of both
mechanical injuries and open lenticels is increased. The spore load
of the washing solution should be kept as low as possible by sorting
out rotten apples before washing, by careful handling to avoid in-
juries, by the periodic renewal of the washing solution, and, where
possible, by the use of a copious fresh water rinse.

In the reduction of loss from blue mold rot good sanitation in and
around the packing house and storage rooms is important. Since culls
are potential sources of infection for other fruit, they should be
stacked outside of the packing house and then disposed of to by-

16 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

product plants or otherwise at frequent intervals (fig. 1,2). Storage
rooms should be kept clean and sanitary at all times, and prior to
each season’s use they should be either whitewashed or well disin-
fected or otherwise thoroughly cleaned and aired before any apples
are brought in. Whitewashing is simpler and generally preferable to
other measures that can be taken. If copper sulfate is added to the
whitewash, its disinfectant properties can be increased somewhat, but
from a practical standpoint this is of questionable value. It is espe-
cially desirable, however, to clean and disinfect the floor, which is not
whitewashed. Thorough scrubbing with water containing 2.5 percent
sodium hypochlorite and a suitable wetting agent is recommended.
There are a number of commercial preparations on the market suit-
able for this purpose.

For disinfection sulfur dioxide, the gas produced by burning sulfur,
can be used. The proportion ordinarily used is 1 pound of sulfur
to 1,000 cubic feet of space. It should be burned in a metal vessel
placed on bricks or otherwise held off the floor. All openings should
be kept tightly closed for an hour or so in order to permit the maxi-
mum concentration of sulfur dioxide to be utilized. Ordinarily
formaldehyde candles can likewise be burned as in household disinfec-
tion, but formaldehyde is less satisfactory than sulfur dioxide because
of the persistence of the odor, and thorough airing out for a con-
siderable period afterward is required. Both sulfur dioxide and
formaldehyde are toxic and injurious to apples, and no fruit
should be placed in the rooms until all traces of gas have dis-
appeared. They are likewise strong irritants to eyes and mucous
membranes, and care must be exercised to avoid contact with the
fumes during or after fumigation. Doors or windows should be
opened to air the rooms thoroughly after fumigation and before
they are entered by workmen. For this reason it is feasible to
fumigate only during the season when the storage space is not
in use.

BRUISING AND OTHER MEcHANICAL INyURIES

The importance of bruising and other mechanical injuries in blue—
mold infection emphasizes the need for preventing such injuries.
Pickers, sorters, and packers should wear gloves or cut their finger-
nails closely to prevent fingernail punctures, and care should be exer-
cised to remove all sand, splinters, and projecting nails in the fruit
boxes or baskets. Pickers should be provided with containers having
rigid sides rather than with picking bags (fig. 6) in order to prevent
bruising the apples when the picker leans against the container, as he
often does in picking from a ladder or in the tree. Pickers should be
required to empty the fruit carefully into the field boxes and should
never be allowed to drop apples more than an inch ortwo. Field boxes
should be filled less than level full, in order to prevent bruising the
fruit when stacked (fig. 7), and care should be exercised in lidding
the market packages to prevent the apples from being cut or badly
bruised. Use of adequate grading and sizing machinery, which moves
the fruit gently on belts or rollers, is an important factor in the reduc-
tion of bruising damage (fig. 8). Bad bruising often results from
not taking adequate precautions in handling the fruit in the packing

HANDLING APPLES FROM TREE TO TABLE ik

“I

FIGURE 6.—Picking buckets are preferable to picking bags, because they afford
more protection against bruising and stem punctures. In emptying, the con-
tainers should be lowered to bottom of the field box so that the apples will
Slip out gently. The boxes should not be filled so full that they cannot be
stacked without injuring the apples as would happen with the improperly filled
box Shown.

house, particularly when the fruit is dumped into the washing or sizing
machinery. If it is poured out of the field crates and allowed to drop
or if it is poured or rolled around in large piles, it is likely to be
bruised and stem-punctured. Unless the apple- handling machinery is
properly adjusted bruising may also occur.

A certain amount and degree of bruising during packing and han-
dling probably are inevitable, but most of the bad dam: age can be elimi-
nated by careful handling, which in turn can ordinarily be secured

467795°—42—_-8

18 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

only by adequate supervision and the use of proper equipment. As an
illustration, the records obtained in some of the United States De-
partment of Agriculture’s studies in the Pacific Northwest on damage
during picking are cited in table 2.

In orchard A the pickers were working without special supervision.
In orchard B there was a picking foreman exercising close supervision
over the work; the very marked reduction in bad bruises and skin
punctures is doubtless due in some measure to this fact. However,
it is probable that it was due in even greater measure to the use of pick-
ing buckets. This is brought out strikingly in the results for orchard
C where there was also a picking foreman exercising as close super-
vision of the pickers using bags as of those using buckets (fig. 6).
The advantage of the bucket was very great in the prevention of
bruising and skin punctures.

NS
NS
RS
BS
S
S
x
\
N
S

FicurE 7.—Field boxes properly filled and stacked to prevent damage to the fruit
and to facilitate cooling on the receiving platform of a packing house. Note that
the individual lots are identified by tags held to the top box by a spring clothes-
pin.

HANDLING APPLES FROM TREE TO TABLE 19

TaRLeE 2.—Comparison of injuries to apples picked into bags and into buckets’

Slightly Badly Skin-

Orchard Picking container Not injured neaieead eniscd punctured
Percent Percent Percent Percent
gaa ies ee tae TS Aaah eee La eRe ee tS oe ee el 34. 1 13.9 50. 2 1.8
Bie ee Bucke ja = eee eee) oe 96. 1 253 133 .3
Cc {pee GE RNa ce ie ae ae See Ey ae 30. 1 24. 2 41.2 4.5
TERS Tate IBUCKCE Se sean ee amet ee 92.5 Teal 8 0

! Unpublished data obtained by R. R. Pailthorp, senior marketing specialist, Agricultural Marketing
Administration.

The apples with slight bruises (table 2) would not be discrim-
inated against on the market, for all such bruises were small and
shallow and did not damage the outward appearance or the keeping
quality of the fruit; however, even slight bruises show up rather
prominently when an ‘apple i Is peeled (fig. 5, B). The bad bruises and
skin punctures, on the other hand, were serious hazards to the keeping
quality of the apples. Even if they did not decay, consumers would
be dissatisfied with them because so much of the fruit would be unfit
to eat. Skin-punctured apples are generally regarded as culls be-
cause it is well known that they are likely to become infected with blue
mold and in consequence are suitable for immediate use only. It is not

Ficure 8—Use of adequate grading and sizing machinery, an important factor
in the reduction of bruising. All the sorters should wear gloves.

20 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

as commonly recognized that apples with bad bruises should be culled
out. Bad bruises not only detract from the sales appeal of the fruit
but are also potential avenues of blue mold infection to almost the
same extent as are skin punctures.

PHYSIOLOGICAL DISEASES
BITTER PIT

Bitter pit, Baldwin spot, or stippin, as it is variously called, is a
physiological disease that 1s found all over the world where apples | are
grown. It occurs as brownish spongy or corky spots or pits in the
flesh Just under the skin and usually is most prevalent at the blossom
end (fig. 5,@). Occasionally the pits are deep-seated and are not evi-
dent reat cutting the apple. The affected part often has a some-
what bitter taste, which accounts for the name “bitter pit.” Bitter
pit does not impair the keeping quality of the apples, but since the
affected parts have to be pared away it reduces the value of the fruit
and of course detracts from its appearance.

No variety is entirely immune, but bitter pit is particularly prevalent
in Baldwin, Gravenstein, Arkansas (Mammoth Black Twig), De-
licious, Yellow Newtown, Rhode Island Greening, and Northern Spy.
The disease is most likely to occur in light-crop years, and apples
grown on young trees are particularly susceptible. Susceptibility to
the disease is also increased when late-season growth is stimulated
by heavy irrigation or rains, fertilization, heavy pruning, or other
means. Bitter pit may begin to appear before the apples are picked
and seems to develop to the greatest extent if they are picked before
they reach proper maturity, Dut as the disease is ‘seldom fully mani-
fested by the time of harvest it is impossible at that time to sort out
all of the apples which will show the pitting. Ordinarily, however,
the diseased apples can be detected within a month or 6 weeks after
they are picked, and if susceptible crops are held until then before
sorting and packing the pitted fruit can be eliminated. If this pro-
cedure were more generally followed, there would be less likelihood of
having to repack affected lots or suffer heavy market losses because of
bitter pit.

JONATHAN SPOT

Jonathan. spot is a superficial skin disease characterized by small
black or brown spots resembling “freckles” scattered over the apple,
particularly on the well- colored part (fig. 5, D). In later stages
these spots may become sunken and the flesh immediately beneath
becomes brown and spongy as the tissue dries out. This disease
affects the appearance and sales value of the fruit rather than its
keeping quality. Jonathans are very susceptible, but the disease
occurs also on many other varieties. The same kind of spot or one
closely resembling it often seriously detracts from the appearance
of Rome Beauty apples. Jonathan spot is only skin deep except in
late stages when underlying flesh tissue becomes brown and dried.

Jonathan spot is a physiological or functional trouble. It occurs
to some extent on highly colored apples left on the tree until they
become overripe, but primarily it is a storage disease that 1s most

HANDLING APPLES FROM TREE TO TABLE yA

serious on apples held at warm temperatures. Ordinarily its pres-
ence is an indication that the apples are ripe or well advanced toward
full ripeness and that their further potential storage life is not long.
It can be prevented almost entirely by picking ‘the apples at the
proper stage of maturity and storing them promptly at a tempera-
ture of 30° to 32° F. The greater the delay in reaching cold storage
the more serious the disease. Storage at temperatures higher than
the range 30° to 32° tends to increase the severity of the disease.

WATER CORE

Water core is a functional disease that appears in the apples before
harvest and gives the flesh a water-soaked or glassy appearance due
to the gorging of the tissues and intercellular. spaces with sap (fig.
9,4). Since it usually becomes worse as the apples reach maturity,
its appearance sometimes causes growers to pick the fruit earlier
than would otherwise be desirable. It is usually most severe on the
highly colored and most exposed apples in the tops of the trees,
while the poorly colored shaded fruit may be entirely free.

When water core extends to the skin of the apple it is easily de-
tectable and such fruit is seldom packed. However, it is often hard
to detect shght water core, especially if it does not come to the skin,
and consequently affected apples sometimes get into storage uninten-
tionally. Growers who are not aware of the hazard likewise may store
water-cored crops.

Since water core predisposes apples to internal break-down (fig.
9, B), it is always hazardous to store affected fruit for late market-
ing. Slight water core in the long-season, hard-textured varieties,
Winesap and Yellow Newtown particularly, may disappear in
storage without leaving any trace; but in the shorter season, softer
varieties, even slight water core is usually followed by internal
break- down, and this almost always happens with more severe water
core in even the harder varieties.

INTERNAL BREAK-DOWN

Internal break-down is a senility disorder that marks the end
of the storage life of apples. It is characterized by brownish
discoloration of the flesh, development of mealiness, and loss of flavor.
in advanced stages the skin of the apple cracks as though from
internal pressure and one can easily press the thumb deep into the
flesh. In earlier stages, however, there may be no outward symptoms
except possibly a dull color of the skin, often confined to the affected
area. Upon cutting, however, a brown discoloration will be found
in the flesh (fig. 9, B), sometimes only in the core region, sometimes
throughout the whole interior, and sometimes localized on only one
side of the fruit. Sometimes, also, the break-down will be found at
severe bruises. In such cases it doubtless is due to the localized
stimulation of respiration, which follows the injury. This is another
reason for careful handling to avoid bad bruises or for sorting out
badly bruised apples.

Since internal break-down is a senility disease, its presence in a
storage lot can ordinarily be taken as an indication that the apples
either were overmature when picked or have become overripe in

22 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

C D

Fictre 9—daA, Water core, characterized by a giassy or water-soaked appearance
of the flesh around the core or main vascular bundles. Such affected apples
are predisposed to internal break-down. 5, Internal break-down, character-
ized by a general mealiness and brownish discoloration of the flesh. C, Soft
scald, which makes apples look as if they might have been rolled on a hot
stove. D, Soggy break-down, which is brought about by causes similar to
those which produce soft scald.

storage. Further holding of such lots is hazardous. As already sug-
gested, the best means of preventing internal break-down is to
harvest the fruit at the proper stage of maturity and to retard its
life processes as much as possible thereafter by holding it at a temper-
ature of 30° to 32° F.

SOFT SCALD AND SOGGY BREAK-DOWN

Some varieties of apples are particularly subject to soft scald or
soggy break-down in cold storage. These diseases are very similar
in nature and cause but differ in their manifestation.

Apples affected by soft scald look as if they might have been rolled
on a hot stove (fig. 9, C). Strips or large spots “of the outer tissues
are affected; the skin is dead and brown but tightly stretched with
a very definite demarcation of the margin. The underlying flesh
is brown and discolored but only in late stages is it more or less

HANDLING APPLES FROM TREE TO TABLE 23

dried out. Earlier, it is soft and juicy. Frequently, rot fungi invade
the fruit through the dead skin. They make black or brown spots
of decay and soon destroy what is left of the apple. Blue mold and
Alternaria are the most common invaders of soft scald tissue. Jona-
than, Rome Beauty, and McIntosh are the varieties most often
affected with soft scald, but it occurs sometimes on other varieties
as well.

While much experimental work has been done on this disease, very
little has been discovered to explain its nature and cause, except
that it is a low-temperature disorder. As a result, no categorical
statements can be made regarding its control. In general, however,
its incidence appears to be reduced or prevented by early harvest and
prompt cold storage at 30° to 32° F. Delay up to 10 days or 2 weeks
in placing the fruit at 30° to 32° seems to increase the tendency to
the disease, but after longer delays the susceptibility of the fruit de-
creases. Well-matured or overmature fruit is more susceptible to soft
scald and should not be stored at temperatures below 36°. The dis-
ease is erratic In its occurrence and may be bad one year and absent
the next.

Soggy break-down is most serious in Grimes Golden and Golden
Delicious and appears to be the manifestation in these varieties of
the same disorder exhibited by soft scald in others. Soggy break-
down differs from soft scald chiefly im its location, being typically a
disease of the flesh, whereas soft scald is confined to the skin and
adjacent flesh. Soft scald has a sharply defined margin in the skin;
in soggy break-down there is a more extensive involvement of the
flesh beneath, without the sharp margin between the sound and the
affected tissues (fig. 9, )). It seems to be associated with the same
storage conditions under which soft scald occurs.

SCALD

Scald occurs in storage and is a more or less generally diffused
browning of the apple skin. At first it is superficial, but eventually
the skin may become soft and slough off and then the flesh beneath
either dries out or is opened to infection by rot fungi. The green or
unblushed portions of the fruit are most affected, and immature apples
are more susceptible than those picked later.

Scald can be understood best by thinking of it as a disease induced
by suffocation or auto-intoxication; that is, it appears to be caused
by products given off by the apple itself. The particular products
involved apparently are connected with the odorous constituents of
the apples.

Scald itself affects the appearance and not the dessert or culinary
quality of the fruit. However, when scald is found, it means that the
further storage life of the fruit is limited because scalded skin is
dead and offers no further protection to the fruit. The disease is
likely to spread rapidly until almost all the surface, particularly the
green-colored areas, is involved. It does not ordinarily begin to
appear until 60 days or more after harvest and commonly is more
serious on apples in cold storage than on those in common storage.
Sometimes it does not become manifest until after the apples are
removed to a warmer temperature and usually it becomes more serious

24 CIRCULAR 659, U.S. DEPARTMENT OF AGRICULTURE

Figure 10.—Control of scald on Grimes Golden cae by use of wraps carrying
odorless, colorless mineral oil to at least 15 percent of their dry weight.

after such transfer, but in such cases it is due to conditions that pre-
vailed during storage, just as when it is found during cold storage.
In the prevention of scald, picking the fruit at proper maturity
is important ; selecting only the best-colored fruit for long-time stor-
age is also important, “but in preventing loss from the disease further
measures must be taken. Since it is due to auto-intoxication effects
in storage, storage practices must be adapted to prevent its occurrence.
If it were practical to provide continuous aeration of every apple,
the injurious odorous emanations could be removed in this way and
scald control could be secured, but it is not possible to do this in com-
mercial packages or under commercial cold- storage practices. The
only feasible method of scald control is the use of oiled paper (fig. 10)
as developed by Brooks, Cooley, and Fisher (2). The oiled paper
can be used either in the form of fruit wraps or shredded. The oiled
paper absorbs the odorous emanations from the fruit and at the same
time to some extent reduces moisture loss from the fruit. Its use is
recommended for all fall and winter varieties of apples. For best
results the apples should be packed in the oiled paper as soon as pos-
sible after harvest. Oiled paper for this purpose is now obtainable
in all apple-growing districts, but growers should make sure that it is
properly prepared and properly used. It should car ry at least 15 per-
cent of its dry weight in an odorless and tasteless mineral oil. When
shredded oil paper is used, at least 14 pound per bushel is required,
and it should be well distributed through the package so that every
apple is in contact with it.

EFFECTS OF PACKAGING

Packaging practices have an important bearing on the subsequent
condition of apples especially as to bruising, and particularly when
apples are displayed to the consumer. It is a strange commentary on

HANDLING APPLES FROM TREE TO TABLE 25

the apple industry that after exercising great care to cull out all skin-
punctured and badly bruised fruit, many packers package their apples
in such a way as to bruise and puncture a large proportion of the good
fruit remaining. Surveys conducted in retail stores in various parts
of the country reveal that the outstanding defect in the apples offered
for sale is bruising—often very bad bruising. In self-service stores
customers naturally do not select badly bruised apples and in other
types of stores such apples are heavily discounted. The offering of
bruised fruit discourages the interest of both seller and buyer, at the
expense of the producer. Often the industry as a whole suffers in con-
sequence, not only because of low profits but also because consumers
turn to more attractive competing fruits, fresh, frozen, or canned,
which may be available in the same store.

Examination of the apples before they are removed from the original
container shows that much of the bad bruising occurs after the fruit
is packed. The greatest single factor in producing this damage is the
insistence of “the trade” on a high bulge or heavy pack so that apples
can be bought by the package and sold by the pound. <A high-bulge
pack will usually bring the producer a few cents more than one that
is merely tight (as distinct from a slack pack) ; so many growers make
it a rule to put on the high bulge. Since such packs are favored in
the wholesale trade but ultimately result in slowing down retail sales.
their widespread use points to a notable lack of coordination among
the various factors concerned in the handling of the commercial apple
crop. However, for the reasons indicated, it is not likely that this
situation can be corrected without an industry-wide effort. If the
grower or packer could reach the consumer directly, the practice would
be abolished very quickly, but when they contact each other only
remotely, and then through intermediaries whose interest in apples as
such is only incidental, the problem is made very difficult.

Results of a survey conducted in the winter of 1940-41 by P. C.
Crandall * in the retail stores of Columbus, Ohio, reported as fol-
lows, show the extent to which bruising is found in apples offered
for sale in retail stores:

In determining the various types of damage, the following classification was
used: 1. Slightly bruised—(Enough damage to affect the external appearance) ;
2. Severely bruised—(Many small bruises or large bruises an inch or more in
diameter) ; 3. Undecayed skin breaks; 4. Decayed skin breaks.
the average grocer’s display [of apples was found to contain the following :]

NOUMMGe totes a ee re nera tee an OO HOU
Slrehtive-Druised = 22-2 a SB Sp Ry Se a ce a SEA AAS,
Severely bruised ____ as = es Ses, ERE ieee Se remac a | (ar: |
Skin breaks, undecayed gee cee ae eZ
Skin breaks, decayed_____ ___ noe fg LSS Nips Be 32.6

. . . Since almost all of the fruit examined came either from the West Coast
or from Ohio, a check was made of the extent and type of damage prevalent
on the fruit from these two regions.

Ohio Western
SiichitlyecDrUiSed ss eS) 2052 24.1
Severely bruised___ eae eae pares pee S551" () 15.3
kine DREAKSe oo 5 so ie Ee Ee es ieee 3.5
Decaved skin: breaks: —< = = = pape < SERS 4.4 2Ot
SOUS erecta BPE a Mee ems Semen tye Te G().O 4. 3

? Reported in: NOLD, TRUMAN. HOW APPLES DECLINE IN VALUE. National Apple Institute,
Columbus, Ohio, Bul. 35, [3] pp. 1941. [Processed.]

26 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

.. . The Western fruit showed a large percentage of bruises caused by high
pressures ... Some boxes of fruit came through with very few if any pres-
sure bruises while others had as high as 50 percent severe bruising. Much of
the damage is due to over-packing the boxes in an effort to secure a heavy
packer.

The Ohio-grewn apples showed severe bruises that were evidently caused,
for the most part, by careless handling. Some of the severe bruising can be
attributed to the packing methods and containers...

The practice of overpacking alone accounts for many of the bruises present
on the apples in the grocers’ displays. For every apple added to form an extra
large bulge, there is at least one severely bruised apple and several slightly
bruised ones. The extra weight added in the form of a large bulge is more
than off-set by the waste and falling-off in condition due to over-packing ...

The type of package used has an important bearing on the preva-
lence and severity of bruising that occurs in the handling of packed
fruit. The continuous stave bushel basket is so generally recognized
as being unsuitable for fruit that it is not necessary to cite experimental
results to prove the point. Nevertheless, this package is still used
to some extent for apples. It is impossible to get and keep a firm
tight pack in this type of basket. The nonrigidity of any side of the
package makes it give under pressure and permits the apples to be
bruised or punctured in much the same way that they are when a bag
is used as a picking container (p.16). The nonrigidity of such baskets
is especially objectionable when they are stacked in storage or during
transit.

Figure 11—Bruised and cut Stayman Winesap apples from the top layer of
tub type bushel basket that was packed too tightly. Note that all apples
except one, which are arranged to show injuries, were cut or badly bruised.

HANDLING APPLES FROM TREE TO TABLE Del

The export tub is much superior to the continuous-stave type of
bushel basket. It has rigid sides and bottom, and the lid provides
enough tension to keep the pack tight when it is properly packed.
Overfilling this package is likely to result in rim cuts as well as in
bad bruising from pressure of the ld (fig. 11). Use of a liner
around the sides and a cushion or pad under the lid, although retard-
ing cooling as shown in table i: is always desirable with bushel
baskets, in order to reduce the hazard of puncturing the apples by
sharp edges of the staves and the ends of the staples, which some-
times project on the inside.

Close sizing of the fruit and “place packing,” or regular alinement,
of the fruit in the box are important in reducing the amount of
bruising in packed apples (fig. 12,8). Western apple packs are far
superior to the usual eastern packs, because for the most part me-
chanical sizing machines are used in the West and variations of more
than one-fourth of an inch in the diameter of apples in a package is
rare. Each size is packed according to a mathematical pattern.
Also each apple is wrapped separately : this affords considerable
protection against bruising. In the East, on the other hand, apples
are often separated into not more than two sizes, those larger or
smaller than a stated minimum, usually 21% inches, 93/, inches, or
3 inches in diameter. Packages may be faced with apples of approxi-
mately the same size, but the “jumble fill” gives opportunity for a
eood deal of bruising both because the apples are not placed and
because when different-sized apples are packed together there is an
uneven pressure of one fruit against another that results in bad bruis-
ing of some of the apples. Table 3 presents typical results obtained

TABLE 3.—Comparison of bruising of Stayman Winesap apples packed in standard
apple box (northwestern box) and 115-bushel eastern crate

Apples badly bruised—

Package
Against each Ageinst
other package
Percent Percent
SE OTOL GL oxo p eae es has SENT ce ne PS a EO GS Ia an aetr
1 De USMElEGASTOMMaCT A Le tees ete ae ee Se ie lh ee ee. & 12 2 29

1 The distribution of this bruising was as follows: Top and bottom layers (against padded lids), 1 percent;
sides and ends (no pads, but paper liners over sides), 13 percent.

2 The distribution of this bruising was as follows: Top layer (against pad), 1 percent; bottom layer (no
pad), 12 percent; sides and ends (cardboard liners but no pads), 16 percent.

in studies made by the United States Department of Agriculture of
bruising of apples packed in a 114-bushel eastern apple crate as com-
pared with packing in a standard apple box. The apples were from
the same lot and were packed at the same time in a Virginia orchard,
after which they were hauled by truck to Washington, D. C., and
held in cold storage for several months before final examination.
Those packed in the standard box were sized to pack 100 per box,
whereas those in the eastern crate were sized “3 inches larger” in
accordance with commercial practice. In the standard box the apples
were wrapped in oiled paper, while in the eastern crate shredded
oiled paper was used. Both packages had liners. Both likewise

CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

28

‘SOpIS posing UO Sexog Suryovjs AQ posnvs sosTn.aq SuIMOYs OAV] VpPIS ‘9 5 yA oy JO
Surzis uadoun AQ posvoasouT jNq IAL] ISA JO ovanssaid AQ posnwVod SasTnaqd Pvq JO SouT[JNo SULMOYS JaAvT PuOdeS ‘g ‘ped vB Aq pojo}0I1d
uveq eARvy plnod YyoryM ‘aofvl doz posTnaq A[OIIAVG

‘

VY :@L oansy ut soy} oxy!] ‘xoq prepueys PoT[JIoAo WOT sofddv postnig—'Z[. anol

HANDLING APPLES FROM TREE TO TABLE 29

had pads under the
lids, but only the
standard box had a
pad in the bottom, in
accordance with cus-
tomary practice in the
eastern United States.
The data in the foot-
notes of table 3 indi-
cate clearly that to
prevent bruising it is
beneficial to place a
pad on the bottom as
well as on the top of
the package.

When western ap-
ples are found to be
badly bruised, it is
usually because of
poor sizing, poor aline-
ment, or overfilling the
boxes (fig. 13), as al-
ready pointed out, or
because of the jolting
which they experience
in the bottom layers ! =
of the car during ship- Figure 13.—Bulging of top, bottom, and sides of
ment. It is not un- standard boxes because of Nee ae ee se
SOTTO to find every Sade We oats oh apples in B atace with
apple in contact with the sides as well as the lids.
the bottom side of the
bottom layer flattened by the vibration or pounding of the floor of
the car (fig. 14). As pointed out by Rose and Lutz (/4), this type of
injury, sometimes mistaken for freezing damage, can be prevented

y use of a resilient cushion liner between the apples and the side
of the box. Some packers customarily use the so-called 4-way pads
that are effective in preventing this damage.

Sometimes apple boxes are overfilled to such an extent that they
bulge on the sides, which are supposed to be rigid, as well as on the
top and bottom (fig. 13). When a standard apple box rocks in a
stack, the fruit is sure to be badly bruised before it reaches the
market. Figure 12, A and C, shows the common appearance of
such fruit when it is unpacked for sale.

Various types of fiberboard containers are likewise in use to some
extent. Some of these are packed similarly to the standard box
and are especially designed to eliminate bruising due to pressure of
top and bottom lids (fig. 15). Others, particularly in eastern sec-
tions, have egg-crate-type cells for the individual apples (fig. 16).

These probably afford maximum protection against bruising, but
because of the diversity of shape required to package different-sized
apples it is difficult to load these satisfactorily in refrigerator cars
or trucks for shipment or to stack them economically in cold storage.
Corrugated fiberboard is a good insulating material and, conse-

30 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

FicurRE 14.—Rome Beauty apples showing typical flattened bruises produced by
jolting or vibration of the standard box against the car floor. Such injury
can be prevented by a cushion liner,

HANDLING APPLES FROM TREE TO TABLE 31

quently, it is some-
what harder to cool
apples packed therein
than in ordinary wood
boxes, especially when
they are sealed up
tightly (fig. 15).

This is especially
true when the cartons ©
are stacked tightly to-
gether like _ bricks,
with no chance to get
cold air around each
package. Another ob-
jection which militates
against the wide- ©
spread use of fiber- Ficure 15.—Corrugated fiberboard box, packed in
board packages is the the Same way as the standard box. Note how this
fact that containers container takes care of the bulge and that when

: ; the package is closed there is no opportunity for
made of this material wentilation®

hold the fruit less rig-

idly in place than wooden containers. Since they are not ordinarily
moistureproof, the high humidity desirable for apple storage causes
fiberboard containers to soften during the storage season. Thus when
the apples come out ripe and in greatest need of protection against
pressure, fiberboard containers are usually even less rigid than in the
fall and are less capable of affording protection than those made of
wood.

PREPACKAGING FOR THE CONSUMER

There have been recurrent attempts to market apples packed in small
containers of various sizes. These have varied from one-half bushel
down to six or eight individual apples packed for the retail trade.
As a rule, apples so packed are not subjected to as much hazard of
bruising as in larger containers, but they are likewise more difficult to
cool quickly and adequately and often are not protected against scald
by use of oiled paper. Ordinarily the fruit is not displayed as well
as in larger packs, and, unless the packages are opened for examination,
customers do not know the condition of the fruit until it has been
taken home. In consequence of these and other factors, unless the
apples are freshly packed it is not probable that use of such packages
can be looked to as a solution of the problem of getting apples to the
consumer in the best condition.

THE SHIPPER’S RESPONSIBILITY

Many apples are shipped to markets long distances from producing
areas and frequently are in transit from 1 week to 2 or 3 weeks before
being unloaded. Most of the shipments are made in refrigerator cars.
The type of protective service that they receive in transit depends on
what is ordered by the shipper. It may be ventilation, refrigeration,
or protection against freezing by heater service.

32 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

Because apples are not a highly perishable fruit, like the peach or
strawberry, for example, and move during the cool seasons of the year,
many shippers order their cars shipped under ventilation. Under this
service no particular control of the temperature of the load is possible,
the vents being kept open at all times when the outside temperature is
above a stated minimum, usually 32° F., and are closed when the outside
temperature drops to this minimum. If the fruit is warm when it is
ioaded, cooling in transit depends entirely on encountering colder out-
side temperatures. If the fruit is colder than the outside temperature,

Figure 16.—Egg-crate type of fiberboard containers, which afford maximum
protection against bruising. The diversity of shapes required for different-
sized apples is a disadvantage.

the load will warm up. This is particularly hkely to occur with ship-
ments from cold storage. Such shipments should never be forwarded
under ventilation service. If transit refrigeration is not desired,
they should be billed “Plugs in. Vents closed to destination.” Thus
the refrigeration stored up in the cold load can be utilized throughout
the trip.

Movement under ventilation is the cheapest service available to the
shipper. From the standpoint of the condition of the fruit, the use
of ventilation 1s justified only with apples that are intended for im-
mediate use. With apples intended for storage at destination, ven-
tilation service jeopardizes their potential storage life because of the
rapidity with which the ripening process proceeds at warm tempera-
tures, as already pointed out (p. 8). Consequently, as a rule, apples
that move under ventilation are not worth as much as those that are
refrigerated in transit. This does not mean that ventilated ship-
ments necessarily sell for less than refrigerated consignments, but it

HANDLING APPLES FROM TREE TO TABLE 33

does mean that they are likely to give less satisfaction to the con-
sumer, thereby doubtless indirectly affecting the market for apples
in general. Shippers who use ventilation service indiscriminately
are to that extent increasing the hazards of the industry and inviting
dissatisfaction among consumers, which must affect the demand for
apples.

Shipments can be billed to move under standard refrigeration or
various modifications thereof. Under standard refrigeration the
bunkers of the car are initially iced to capacity and are refilled at all
regular icing stations en route (usually at least once every 24 hours),
and the car is delivered with bunkers at least three-fourths full.
When shipments are precooled or are loaded out of cold storage and
move under standard refrigeration, maximum protection is secured.

Sometimes modified refrigeration services can be utilized to effect
savings in cost without sacrificing efficiency of refrigeration, and
shippers are utilizing such services to an increasing extent. It is
possible, however, that some apple shippers are going too far in this
direction. The apple does not ripen as rapidly as some other fruits,
but every day that it is kept above the optimum storage temperature
means a progressive shortening of the time before it will become full
ripe, and presently thereafter, overripe and undesirable or unsalable.
Consequently, the use of protective services providing relatively warm
temperatures during the transit period interjects an element of
hidden damage to the potential storage quality of the fruit. The
degree to which this damage may be hidden, or the time at which
it will become apparent in the ripening of the fruit depends on the
condition of the apples at time of shipment and their temperature
while in transit. It is more likely to be serious with varieties like
the Jonathan, Rome Beauty. and Delicious, which are often left on
the trees until past proper picking stage in order to get more red
color, than with later keeping varieties, such as Winesap and Yellow
Newtown.

The effects of hidden damage of the type described are probably
seen to the greatest extent in shipments that move under heater
service. Mallison, Gorman, and Hukill (72) found that the use of
heater service often means the occurrence of temperatures in the car
during cold weather that call for the use of refrigeration during
warmer weather. Such inconsistency is due to the impossibility of
closely regulating the amount of heat supplied and the distribution
of that heat in the car with ordinary heating devices and the method
of using them now commonly employed. As pointed out by Mallison
and others (72), much improvement should be possible in heater
service by the use of thermostatically controlled car heaters or of
manually controlled heaters operated upon the basis of temperatures
inside the car, rather than of outside temperatures. Under present
practices freezing temperatures are sometimes found in the bottom
of the load when temperatures are up to 60° F. or higher in the upper
layers. Unquestionably a great deal of damage has been done to
winter shipments of Delicious and other varieties, which are espe-
cially prone to become mealy, by the heater service used to protect
the fruit against freezing while in transit. This is particularly true
of apples grown in the Pacific Northwest and shipped to eastern

markets.

34 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

THE DEALER'S RESPONSIBIEM Y

From the foregoing discussion it might appear that the condition
and quality of the apples have been predetermined by what has hap-
pened to the fruit before it reaches the dealer. This is true in large
measure, but there are a number of things that the dealer can do to
reduce deterioration of the apples that he buys for resale. To list
them would be for the most part to repeat the factors already enu-
merated, but with special applcation to conditions under the dealer’s
control.

It should be unnecessary to emphasize further that apples begin
to deteriorate as soon as they are mature and begin to ripen. The rate
of deterioration varies with the variety and particularly with the
way in which the individual lot of apples is handled, especially with
the temperature at which it is held. It should be axiomatic then that
apples do not improve in storage and that the best that can be done
is to slow up the rate at which. they will deteriorate. Even if they
are good and sound when stored, they are bound to be less so when
they are removed for sale.

The first responsibility of the dealer should be to buy good
front; but this does not necessarily mean buying fruit marked “Extra
F ancy” or “U.S. No. 1.” These grade designations, even though they
may have honestly described the quality of the fruit at the time of
packing, do not reflect changes in condition, such as ripeness, decay,
and scald, that have taken place during the storage period. The buyer

Figure 17.—Retail display of apples mostly in their original containers, in which
they keep best, and away from potatoes and root crops, from which they may
absorb odors, and from leafy vegetables, which are sprinkled to keep them
fresh.

HANDLING APPLES FROM TREE TO TABLE 35

fot) Apples

@.
a eA 7h
A 2 G Ss &; od wd
an

aoe of the QPEWARD

Juicy

Figure 18.—Attractive mass display of apples. Careless handling and piling of
such large masses of apples May cause bad bruising and stem punctures and
result in decay unless the fruit is consumed quickly.

should have the apples inspected at the time he intends to purchase
them in order to determine the extent to which deterioration has
progressed since the apples were graded and packed. Most dealers
make such inspections themselves or have the opportunity to do so.
Hence, if they buy fruit that is badly bruised, overripe, more or less
decayed, misshapen, wormy or scale infested, or culls, presumably
they do it with the intent to offer that class of fruit to customers.
Next to bad bruising, overripeness is the greatest cause of complaint
among retail purchasers. How often is heard the criticism ; ‘‘Nice-
looking large red apples, but mealy and tasteless.” That always
means overripe apples. How fast do apples get overripe? The
answer depends on the temperature—in the retailer’s store as well as
in commercial storage or in the hands of the grower after harvest.
As pointed out earlier (p. 8), apples ripen about twice as fast at
70° as at 50° F., twice as fast at 50° as at 40°, and twice as fast at 40°
as at 82°. If they are ripe when bought for sale, some kinds (Deli-
cious in particular) can become overripe and mealy in 2 or 38 days at
ordinary store temperatures and in even less time if they are piled
behind windows for display and are not protected against hot sun-
shine. The safest procedure for a retail merchant is to regard apples
from cold storage late in the season as being as perishable as peaches
at the height of their season and to move the apples into consumers
hands before they have a chance to get overripe and out of condition.
Apples purchased 1 in small lots usually cost more than those obtained
in large quantity ; hence, retailers may buy more than they can dispose

36 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

of before the fruit gets overripe. Unless refrigeration facilities can
be utilized, the merchant who would sell only apples not beyond their
prime should obtain fresh stock from cold storage at intervals of not
over 2 or 3 days rather than hold a surplus at warm temperature. If
some of the fruit must be held over, especially during warm weather,
the best place to keep the apples is in a retrigerator. Some stores
have a special walk-in refrigerator for fruits and vegetables; others
utilize space in the meat cooler. If refrigeration is not available, the
apples will benefit by being held in a cool, well-ventilated place,
perhaps in the stockroom where screened or barred windows can be
left open or in a cool basement room.

Packed boxes should always be stacked on the side (fig. 13), never
on the top, which is bulged to hold the fruit in place, or on the ends,
as this will concentrate the weight on a smaller area and increase the
chances of bruising. Only when the top is removed and pressure is
released, is it safe to let the boxes rest on the bottom lid. Bushel
baskets should be staggered by placing one basket on the edges of two
others, keeping all pressure away from the center of the lids (fig. 4).
To provide good air circulation, which is needed to keep the fruit cool
In warm weather, containers of apples should be kept away from out-
side walls and should be placed on a false floor or slatted platform with
3 or 4 inches of air space beneath. These measures will also reduce
danger of freezing damage in cold weather.

In displaying apples the fruit should be kept away from potatoes,
onions, and other root crops from which they may absorb odors.
Apples should also be kept away from wet, green leafy vegetables
that are sprinkled to keep them fresh, and of course the apples them-
selves should never be sprinkled, as this may stimulate decay. How-
ever, apples deteriorate rapidly when exposed in warm, dry air; hence,
most of the stock should be kept in the original containers (fig. 17).
Displays should not be made near radiators, stoves, or sunny windows,
and they should be of such size that they will have to be renewed
frequently with fresh stock.

Frequently dealers make mass displays of apples (fig. 18), remov-
ing them from the contamers and piling the fruit in pyramids or
otherwise in large lots. This contributes to bruising damage unless
very carefully done. In self-service stores, where customers are free
to select the fruit that they purchase and where in consequence it may
be handled over a good deal, the bruising is increased considerably
after the apples are put on display. The extent of this damage, of
course, varies, but that it may be serious is shown by the conditions
observed in one of the stores covered by Crandall in his survey.’
He examined the fruit in original containers just as it was delivered
to the store and also some of the same lots as they were displayed for
sale. The results presented in table 4 show that, although handling
in the store increased the damage considerably, most of the bruising
was present when the apples were unpacked.

These results reported by Crandall are in general agreement with
those reported by Kross and Slamp,? who made a somewhat similar
study in New Jersey. They examined apples on display in retail

2 See footnote 2.
*Kross, JOHN I., and Stamp, K. R. SELLING APPLES DIRECTLY TO RETAIL STORES. N. J.
Agr. Col. Ext. [unnumbered], 9 pp. New Brunswick, N. J. 1941. [Processed.]

HANDLING APPLES FROM TREE TO TABLE BV

TABLE 4.—Condition of apples before they were unpacked and after display

for sale
Sound in ;
Variety original patel ee

package prey.

Percent Percent
ONS thats e ene eee e em tn See So Ce el eee Meme Se ae 64
CLoldenah) Cli Cts eee ee ee ee Se eee. 72 48
TREN hi ta ee EN a ee Oe ee er eS ee ee 93 | 43
CREGET TNO eee eee han ee eee ee Bs ees ine et 2 2 eee eee ere 71 56

stores and found that 42 percent of the apples showed old bruises and
only 8 percent had fresh bruises, apparently as a result of handling
in the stores.

If the retailer would give his trade the kind of apples that will
stimulate demand, he must consider the variety as well as grade and
condition. In order to make even such a rough classification as eating
apples and cooking apples, as is frequently done in grocery stores, the
dealer needs to know something about the principal ‘commercial varie-
ties so that, for example, Rome Beauty, York Imperial, or even Ben
Davis will not be offered as eating apples or Delicious as a good
baking apple because it has good size. He also needs to know when
each is in season. It is not uncommon to find Jonathans and Wine-
saps offered together. In the fall only the former could give satis-
faction, but in late spring the Winesap would be preferred.

While there are upwards of 200 varieties of apples grown more or
less in the United States, the list of those that may be regarded as the
principal commercial kinds is comparatively short and is given in
table 5 where they are classified as to color, whether they are best for
eating or cooking, whether their flesh is soft or firm, and when they
are in season or can be expected to be at their best. More information
on apple varieties can be found in Farmers’ Bulletin 1883 (8).

The information in table 5 is needed for the intelligent buying and
handling of apples. Some of the varieties listed are good ‘for both

eating out of hand and for sauce, pie, or other culinary - purposes, but
others are best adapted to one or the other of these uses. Yellow
Transparent, for example, is too acid to be appreciated by most people

TABLE 5.—Characteristics of principal commercial varieties of apples

Flesh
Variety Color Principal use when Marketing season
ripe
Yellow Transparent__.____| Yellow_.__| Cooking ________________ Soff=2s2=" July to August.
Gravenstein._____________ Striped___ __.| Eating and cooking_____|___do_______| July to September.
Wealthy ese FC Gees | ae GO 222 A ee TS eae OO ee September to December.
INEGInT os hese ae eo |e doe | 2 dOL2{ 2252 | eee dos = September to January.
Grimes Golden___________ Vellowz-2=|=0—= 002222 2 ee ee Nig! Do.
Jonathantes=tee ere Redes asses (Rec ae GG sect ae Sa eeeee | Bare dos s= September to February.
ID YE) WO ee re doses Hating 2s See eee a doe September to April.
Rhode Island Greening__| Green____- Cooking = 2s oe wanianeen ie dose October to March.
Golden Delicious_________ Yellow____| Eating and Cookin oes | send Ouse October to April.
ork7impenial<-/3-=> =< = Reda — Cooking__ ee AR ard October to March.
Stayman Winesap_-___-___]__-do_______ Eating and. cooking ___ || Dita se Ss November to April.
Baldwin_ Been ets ets (1 Qa es OY 2 2 se ee Be do Do.
Rome Beauty. <ei oe a ee Gdosesa: Cooking_ aoe pad _do_______| Novemberto May.
Yellow Newtown_-_-_-___- Green or | Eating and cooking _ ee lerar diss =°¢ January to June.

yellow. |

38 CIRCULAR 659, U. S. DEPARTMENT OF AGRICULTURE

for eating out of hand, but for sauce or pie it is considered one of the
best. Delicious, on the other hand, is so lacking in acidity that it is not
adapted for most culinary uses but is the leading variety for the fruit-
stand trade.

The character of the flesh of a variety when ripe is an important
consideration for all handlers of apples, since in general it indicates
the susceptibility of the fruit to bruising and how it will withstand
handling, especially in bulk or in the retailer’s bins. Important in
this connection also is the color of the fruit. Those listed as “soft”
in table 5 are most likely to become badly bruised, while those listed
as “hard” are less likely to be damaged by ordinary handling. Those
marked “firm” are intermediate in this respect. As a rule varieties
that are solid yellow or green show bruising much more readily than
red or striped varieties, although actually they may not be bruised
to any greater extent. Consequently they have to be handled much
more carefully if the appearance of the apples is not to be affected.

The marketing season indicated for the different varieties in table 5
is the period during which commercial supplies of these apples should
be at their best. If found on the market earlier the apples are likely
to be unsatisfactory either because of immaturity (being picked too
soon) or because they have not had a chance to ripen sufficiently.
If they are offered later than their normal marketing season they
may still be in good condition and may still give consumer satisfac-
tion if they have received exceptional care in handling and storage
but the hazards of their soon becoming overripe or of quick break-
down are greatly increased. Much of the complaint about overripeness
in apples is due to their being stored beyond their normal marketing
season.

THE INDUSTRY'S RESPONSIBILITY

The most practical approach to the problem of getting good apples
to the consumer seems to lie in a close coordination of all elements
in the industry to apply good handling methods at all times during
the marketing process according to the principles outlined herein.
For any such effort to succeed will doubtless require the initiative
to be taken by apple producers and shippers. They are not only the
most immediately concerned but also possess the requisite knowledge
and appreciation of the technical requirements in handling the apple.
Their business is often tied up closely with apples alone, whereas
to others in the trade apples are only one item of merchandise.
Success of such an undertaking also is dependent on sustained in-
dustry-wide cooperation rather than on the sporadic initiative of
individuals. It can perhaps best be attained through the specialized
organizations that have been set up for the purpose of promoting
the sale of apples generally. With adequate support of these organi-
zations by growers and shippers, and close-knit cooperation between
such organizations in different parts of the country particularly,
much could be done. Success would require an educational or demon-
stration program based on two fundamentals that apply to all m
the industry: (1) The intrinsic worth of the apple as an article of
diet and (2) the necessity of keeping apples in good condition to
maintain their intrinsic worth as food.

(7)

(8)

(9)

(10)

(11)

(12)

(13)

(44)

(15)

(16)

(17)

(18)

LIFERATURE-CIGED

ALLEN, F. W., and PENTZER, W. T.
1936. STUDIES ON THE EFFECT OF HUMIDITY IN THE COLD STORAGE OF FRUITS.
Amer. Soc. Hort. Sci. Proc. (1935) 33 : 215-223, illus.
Brooks, C., Cooiey, J. S., and FISHER, D. F.
1919. NATURE AND CONTROL OF APPLE-SCALD. Jour. Agr. Res. 18: 211—240.
CooLEy, J. S.. and FisHer, D. F.

1920. DISEASES OF APPLES IN STORAGE. U.S. Dept. Agr. Farmers’ Bul. 1160,

20 pp., illus. (Revised 1935.)
GARDNER, F. E., MARTH, P. C., and BATJER, L. P.

1940. SPRAYING WITH PLANT GROWTH SUBSTANCES FOR CONTROL OF THE PRE-
HARVEST DROP OF APPLES. Amer. Soc. Hort. Sci. Proc. (1989) 37:
415-428.

HALLER, M. H.
1941. FRUIT PRESSURE TESTERS AND THEIR PRACTICAL APPLICATIONS. U. S.
Dept. Agr. Cir. 627, 22 pp., illus.

Lui, J. M., and MAtrison, E. D.

1941. THE RELATION OF FIRMNESS TO RIPENESS OF EASTERN-GROWN APPLES.
U. S. Dept. Agr. Cir. 579, 22 pp., illus.

Kipp, F., and WEST, C.
1935. THE REFRIGERATED GAS-STORAGE OF APPLES. [Gt. Brit.] Dept. Sci. and
Indus. Res., Food Invest. Leaflet 6, 12 pp., illus.
MaGeness, J. R.
1941. APPLE VARIETIES AND IMPORTANT PRODUCING SECTIONS OF THE UNITED
STATES. U.S. Dept. Agr. Farmers’ Bul. 1883, 32 pp., illus.
DIEHL, H. C., and HALLER, M. H.
1926. PICKING MATURITY OF APPLES IN RELATION TO STORAGE. U. S. Dept.

Agr. Dept. Bul. 1448, 20 pp., illus.

DIEHL, H. C., HALLER, M. H., and others.

1926. THE RIPENING, STORAGE, AND HANDLING OF APPLES. U. S. Dept. Agr.
Dept. Bul. 1406, 64 pp., illus.

and TAYLor, G. F.

1925. AN IMPROVED TYPE OF PRESSURE TESTER FOR THE DETERMINATION OF FRUIT
MATURITY. U.S. Dept. Agr. Dept. Cir. 350. 8 pp., illus.

MALLISON, E. D., GORMAN, E. A., JR., and HUKIIL. W. V.

1937. PROTECTION OF APPLES AND PEARS IN TRANSIT FROM THE PACIFIC NORTH-
WEST DURING THE WINTER MONTHS. U.S. Dept. Agr. Tech. Bul. 550,
5d) pp.. illus.

Rose, D. H., Brooks, C., FISHER, D. F., and BraTLey, C. O.
1933. MARKET DISEASES OF FRUITS AND VEGETABLES : APPLES, PEARS, QUINCES.
U. S. Dept. Agr. Misc. Pub. 168, 71 pp., illus.

and Lutz, J. M.

1933. BRUISING AND FREEZING OF APPLES IN STORAGE AND TRANSIT. U. S.

Dept. Agr. Tech. Bul. 370, 15 pp., illus.

WRIGHT, R. C., and WHITEMAN, T. M.

1933. THE COMMERCIAL STORAGE OF FRUITS, VEGETABLES, AND FLORISTS’ STOCKS.

U. S. Dept. Agr. Cir. 278, 40 pp. (Revised 1941.)
Smock, R. M., and VAN DoREN, A.
1941. CONTROLLED-ATMOSPHERE STORAGE OF APPLES. N. Y. (Cornell) Agr.
Expt. Sta. Bul. 762, 45 pp., illus.
Wricur, R. C.
1942. THE FREEZING TEMPERATURES OF SOME FRUITS, VEGETABLES, AND FLO-
RIsTs’ stocKs. U.S. Dept. Agr. Cir. 447, 12 pp. (Revised.)
LuMspbEN, D. V., WHITEMAN, T. M., and ByRNEs, J. W.
1941. SOME EFFECTS OF APPLES AND OTHER FRUITS ON THE STORAGE LIFE OF CUT
FLOWERS. Ice and Refrig. 100: 149-150, illus.

39

U. $. GOVERNMENT PRINTING OFFICE: 1941