The Kennewick courier-reporter. [volume] (Kennewick, Wash.) 1914-1938, 1923-03-01


the fruit is picked until it reached the
storage room are usually as import
ant in determining the conditions
maintained in the storage rooms As
the fruit develops on the trees, up to
the time for picking, there are GER
tain well-defined changes taking place.
Tn most obvious is, of course, an in
crease in size and an increase in the
amount of color on the fruit. AS
sociated with these changes, however,
is a constant increase in the percent
age of sugar in the fruit and a con-
slant decrease in the acidity. Even
more important than these changes,
however, from the storage stand
point, are the changes that occur in
the skin of the fruit.
As the fruit approaches maturity
on the tree, the skin becomes more
waxy or suberized. During the slow
growth on the tree there are certain
pores or lenticels through hte skin
which are always more or less open.
AS the fruit ripens these become
corked over and are sealed. Conse-
quently, when either pears or apples
ar mature on the tree and really ready
for picking, the skin represents al
most an impermeable covering to the
fruit. Moisture will pass through
this only very slowly.
1t is common experience, for ex-
ample, that Bartlett pears picked too
early will tend to wilt in transit or
in storage. Apples picked when i'm
mature will likewise tend to wilt vero
rapidly while in storage. This wax
ing over or sealing Of the skin of the
fruit is associated with color devel-
opment. It will oftentimes be noted
that an apple is badly wilted on the
green side while on the blush side
is till plump and turgid.
From this discussion it can be seen
that the time Of picking is of ire
mendous Importance in the proper
storage of apples and pears. Not on
| ly does immature fruit tend to wilt
badly but it is lacking in quality and
flavor, due to the fact that it has
been removed from the tree before
the sugars and other flavoring COM
pounds have attained full develop
ment. Also such fruits, in the case
of apples, tend to develop storage
scald very readily and in the case OF
pears tend to blacken when held fo1
a long season Of cold storage.
Most of the Bartlett pears shipped
from the Pacific Coast to eastern
markets must be picked so green in
order to arrive on the market in firm
condition that they are not suitable
for long time holding in cold stor-
age. Experimental work has shown
very definitely that it is only the
early picked Bartlett pears which tend
to blacken, or as we have used the
term, develop "pear scald," in cold
storage. The claim has oftentimes
been made that this injury.is the re-
suit of the freezing of the fruit in
storage, but it has been found that
it will develop even more quickly in
fruit held at 35 to 30 degrees F., than
it will in fruit held at 80 degrees.
Following picking, there are GER
tain well-defined changes that occur
in the fruit The starch quickly
changes to sugar and there is rap
id drop in acidity There is also a
continuous softening of the fruit, due
to changes in the cell structure.
These changes occur very rapidly in
fruit held at higher temperatures
it is the purpose of cold storage to
retard these changes as much as pos
sible. They can be entirely stopped
only by freezing and this is what is
accomplished in the frozen storage
of berries, cherries, etc. In apples
and pears, however, these changes,
which we term ripening, can be very