10. MINERAL MATTER IN CEREALS.--Cereals contain seven or eight of the minerals required in the diet. Such a variety of minerals is sure to be valuable to the human body, as it is about one-half of the whole number required by the body for its maintenance. Since, as has already been explained, much of the mineral matter lies directly under the coarse outside covering, some of it is lost when this covering is removed. For this reason, the grains that remain whole and the cereal products that contain the entire grain are much more valuable from the standpoint of minerals than those in which the bran covering is not retained. If a sufficient percentage of minerals is secured in the diet from vegetables, fruits, and milk, it is perhaps unnecessary to include whole cereals; but if the diet is at all limited, it is advisable to select those cereals which retain the original composition of the grain.
11. WATER IN CEREALS.--Cereals contain very little water in their composition. This absence of water is a distinct advantage, for it makes their nutritive value proportionately high and improves their keeping quality. Just as the strength of a beverage is lowered by the addition of water, so the nutritive value of foods decreases when they contain a large amount of water. On the other hand, the keeping quality of cereals could scarcely be improved, since the germs that cause foods to spoil grow only in the presence of water. This low proportion of water also permits them to be stored compactly, whereas if water occurred in large amounts it would add materially to their bulk.
12. CELLULOSE IN CEREALS.--In addition to the five food substances that are found in all cereals, there is always present another material known as cellulose, which, as is pointed out elsewhere, is an indigestible material that occurs on the outside of all grains, as the bran covering, and covers the starch granules throughout the inside of the grain. In fact, it forms a sort of skeleton upon which the grains are built. As long as the cellulose remains unbroken, it prevents the grain from being digested to any extent. However, it forms a valuable protective covering for the grain and it has a certain value, as bulk, in the diet, a fact that is ignored by some persons and overrated by others. It is well to include at least some cellulose in cereal foods when they are taken in the diet, because its presence tends to make food less concentrated.
13. TABLE SHOWING COMPOSITION OF CEREALS.--Not all grains, or cereals, contain the same amount of food substances and cellulose; that is, while one may be high in protein it may be lacking in some other food substance. The relation that the various grains bear to one another with regard to the food substances and cellulose is clearly set forth in Table I. In this table, under the various food substances and cellulose, the grains, with the exception of millet, are mentioned in the order of their value, ranging from the highest down to the lowest in each of the food substances and cellulose. Thus, as will be seen, wheat is highest in protein and rice is lowest, oats are highest in fat and rye is lowest, and so on. Also, as will be observed, while wheat is highest in protein, it is, as compared with the other cereals, sixth in fat, fourth in carbohydrate, fourth in cellulose, and fifth in mineral matter. In this way may be compared all the other cereals to see in just what way they are of value as a food.
TABLE I
| COMPOSITION OF CEREALS | ||||
| Protein | Fat | Carbohydrate | Cellulose | Mineral Matter or Ash |
| Wheat | Oats | Rice | Oats | Oats |
| Rye | Corn | Rye | Buckwheat | Barley |
| Oats | Barley | Corn | Barley | Buckwheat |
| Barley | Buckwheat | Wheat | Wheat | Rye |
| Corn | Rice | Barley | Rye | Wheat |
| Buckwheat | Wheat | Buckwheat | Corn | Corn |
| Rice | Rye | Oats | Rice | Rice |
CEREALS AS A FOOD
USES OF CEREALS