Besides the cereals already mentioned, a number of products of cereals are extensively used in cookery, chief among them being flour, corn starch, and other starches. Although every housewife should possess knowledge of the uses of each of these, instruction in them is not given until later.
This Section includes particularly the study of grains--whole, cracked, flaked, and those made into grits or meal--and the use and the serving of them, as well as ready-to-eat cereals, which are commonly referred to as breakfast foods.
The only additional foods to which attention is given at this time are macaroni, spaghetti, and foods of a similar nature, for as these are made from wheat they are truly cereal products. In their preparation for the table, the rules that govern the other cereal foods apply also in a large measure to them.
COMPOSITION OF CEREALS
5. The composition of all cereals is similar, yet each one has its distinguishing feature. While all the five food substances--water, mineral matter, protein, fat, and carbohydrate--are to be found in cereals, they occur in different quantities in the various kinds. Some contain large quantities of protein and others practically none, and while certain ones have considerable fat others possess comparatively small quantities.
A characteristic of all cereals, however, is that they contain a large amount of carbohydrate and a small amount of water. It is well to remember, though, that while the food substances of cereals are found in sufficient quantities to sustain life, they will not permit a person to live for long periods of time exclusively on this form of food.
Likewise, it will be well to observe that the foods made from a certain grain will be quite similar in composition to the grain itself; that is, any change in the composition of the foods must be brought about by the addition of other substances.
All grains are similar in general structure, too. The largest proportion of carbohydrate lies in the center, this substance growing less toward the outside of the grain. The protein lies near the outside, and grows less toward the center.
Fat is found in small amounts scattered through the entire grain, but most of it is found in the germ, which is a tiny portion of the grain from which the new plant sprouts. The mineral matter of cereals is found chiefly just inside the bran, or outer covering, so that when this covering is removed, as in the process of preparation for food, a certain amount of mineral matter is generally lost.
PROTEIN IN CEREALS.
The cereals are essentially a carbohydrate food, but some also yield a large proportion of protein. In this respect they differ from the animal foods that produce the principal supply of protein for the diet, for these, with the exception of milk, do not yield carbohydrates. The grain that contains the most protein is wheat, and in the form in which protein occurs in this cereal it is called gluten, a substance that is responsible for the hardness of wheat.
The gluten, when the wheat is mixed with water or some other liquid, becomes gummy and elastic, a fact that accounts for the rubbery consistency of bread dough. Cereals that contain no gluten do not make bread successfully. Next to wheat, rye contains protein in the greatest amount, and rice contains the least. Although protein is the most expensive of the food substances, the kind of protein found in cereals is one of the cheaper varieties.