Of all the different methods of cooking starches, by far the most common, and, therefore, the most important, is the process called baking. While it is not possible in this volume to go into the subject with the thoroughness that it deserves, the principal points deserve some mention. They may be briefly stated as follows:
(1) The flour must be made into a dough in which are incorporated substances that produce a gas called carbon dioxide, which, forming in innumerable small bubbles throughout the mass, cause the whole to swell; when this is completed the bread is said to have "risen." Of course the object of this is to produce a thorough breaking up of the sticky dough--with the result that when the bread is finally cooked it is light and fluffy, and can be readily masticated.
(2) After the process just described has been completed the bread should be thoroughly cooked, for reasons which have already been explained.
(3) After cooking has been accomplished the bread should be thoroughly dried, either by keeping it hot until this occurs, or, what is better, permitting it to remain warm for a time and then allowing the process to be completed in a natural way by putting the bread aside for several days. It is necessary for bread to be dried in order that it may be thoroughly soaked in saliva during the process of chewing.
If the principles above enunciated be properly followed out, good wholesome bread will result. There are, of course, many details connected with the preparation of food known to expert cooks into which it will not be possible for us to go here, and for which the reader is referred to any good cook-book.
Some starchy foods such as rice and potatoes, do not lend themselves readily to the production of breads, and are consequently usually cooked in some other manner. It cannot be too strongly insisted upon that they should be rather _steamed_ than boiled,--the process being usually carried out by placing a small amount of water with them and allowing it to boil away; we should remember also that the principles just insisted upon in connection with making bread apply here with equal force--we should cook thoroughly and serve both as dry as is possible.
_Cooking of Meats._--Here again it is necessary to insist upon the necessity of thorough cooking. The error has long prevailed that raw meats are wholesome, but within recent years it has been clearly demonstrated that this old view is erroneous. The muscle-fibers that constitute the bulk of the nourishment of meats are separated from each other by a substance which cannot be acted upon by the juices of the stomach until it has been heated to a temperature which results in the cooking of the entire mass. It is true that the muscular substance proper may be digested without heat--resembling in this way the white of the egg, to which it is chemically closely related; by scraping meat with some dull instrument the muscle fibers may be separated in a more or less pure state--leaving the substance that requires heat in order to become digestible behind--and after having been removed in this way, of course, may be eaten in a raw or semi-cooked condition without ill effects. In preparing meat it is not absolutely essential that it be cooked until thoroughly "done"--a slight tinge of red being allowable.