In no par t of our dail y wants do we show our dependence on the vegetable kingdom so much as in our food. All our food is, directly or indirectly, of vegetable origin; although we eat the flesh of certain animals, the animals themselves derived their support, all through their lives, from plants of one kind or another.
Man, in every part of the globe, makes bread of some kind his staple food and, although the bread is not always made of the same sort of material, it is in every case a vegetable substance.
The cereals, or corn grains, form the bread-making materials for the greater part of civilized mankind. Indeed, they provide the staple food of more than four-fifths of the population of the globe. These grains contain two important food materials-starch and gluten. One, you already know, is valuable as a fuel-food, the other as a tissue-forming food. The various corn grains owe their relative importance as food-stuffs chiefly to the amount of gluten which they contain.
The gluten of the grain always resides in the outer part, immediately under the skin or husk. This explains whythe bran of English wheat, which consists largely of this outer skin, contains more gluten than the finest white flour. Fine white flour is obtained only by sifting the meal through sieves after it is ground. The sifting removes all the particles of bran. Sometimes the meal is used without sifting, just as it leaves the mill, in fact. It is then known as whole-meal.
The bran of English wheat contains 16 percent gluten;the whole-meal 12 percent; fine white flour rarely contains 10 percent. Bread, therefore, made from whole-meal is more nutritious than that made from fine, sifted, white flour.
Reference has been made to the relative value of the corn grains, and it will be well now to compare them one with another. Oatmeal is very rich in gluten; it contains about 16 percent of this substance-that is, about the same proportion as we find in the bran of English wheat.
Barley and rye contain about the same proportion of gluten as is met with in wheaten flour, but the meal of both is coarser in flavor and color, and the bread made from them, instead of being light and spongy, is heavy and close. Rye forms the chief food of the masses in Russia. In this country it is grown, and cut green for feeding horses.
Rice is remarkable among the corn grains for containing the smallest proportion of gluten. Even in the undressed rice, or paddy, such as is eaten by the people of the East, there is not more than 7 or 8 percent-about half theamount we find in oatmeal, and the grain as we use it contains much less, because, with the removal of the outer skin, much of the gluten is also removed.
Maize contains only about 9 percent gluten, but it is richer in fatty or oily matter than any of the other grains. This makes it more easy of digestion, and it is well adapted for fattening animals.
Let us see now how Nature suits her foods to the requirements of the various populations of the world.
