108. DRYING consists in removing the moisture contained in foods by
evaporation and thus rendering them less susceptible to the attacks of
undesirable bacteria. _Dried foods_, as foods so treated are called,
will not replace fresh or canned foods. However, they are valuable in
many cases and possess some advantages over such foods. For example, the
weight of dried foods is very greatly reduced, the storage space
required by them is much less, and they are easy to keep without
spoiling and easy to transport. Likewise, the containers for such foods
are less costly than those required for canned foods and they are easily
procured, since paper boxes or paper bags are satisfactory. In fact, the
housewife, by taking care of the bags and boxes that come into the home,
can easily provide all the containers she will possibly need at
practically no cost.
109. The water in food that is to be dried may be evaporated by applying
heat, by bringing the food in contact with moving air, or by subjecting
it to a combination of both of these methods. The heat for drying may be
obtained from the sun, as in the _sun-drying method_, or from the stove,
as in the _stove-drying method_, while moving air for evaporating
moisture may be obtained from an electric fan, as in the _electric-fan
drying method_.
In the application of any of these drying methods, however, it is
important to note that the more surface of food there is exposed, the
more quickly will evaporation take place. Drying should therefore be
done on devices constructed in such a way that air may pass up through
food, as well as across its surface. In drying foods, the racks should
be turned frequently, so that all parts will be exposed equally to the
heat or the currents of air. Also, the food must be turned over often,
in order that all parts will dry evenly.
110. Any fruit or vegetable may be dried if the method is properly
applied, but there is usually more or less change in both the flavor and
the color of the dried food. The more rapidly the drying can be done,
the more natural will the color and flavor remain; whereas, the longer
the process is continued, the greater will be this change.
Foods should be dried when they are in such quantity that they cannot be
used to advantage in the raw state, when there is no market for them,
when the owner cannot afford to give them away, and when home canning
ceases to be practical and profitable. In other words, if it is not
practical to save foods in another way, they should be dried.