Page:Popular Science Monthly Volume 25.djvu/73

Rh No such precautions are demanded in the boiling of vegetables. The work to be done in cooking a cabbage or a turnip, for example, is merely to soften the cellular tissue by the semi-solvent action of hot water; there is nothing to avoid in the direction of overheating. Even if the water could be raised above 212°, the vegetable would be rather improved than injured thereby.

The question that now naturally arises is, whether modern science can show us that anything more can be done in the preparation of vegetable tissue than the mere softening in boiling water. In my first paper I said that the practice of using the digestive apparatus of sheep, oxen, etc., for the preparation of our food is merely a transitory barbarism, to be ultimately superseded by scientific cookery, by preparing vegetables in such a manner that they shall be as easily digested as the prepared grass we call beef and mutton. I do not mean by this that the vegetable we should use shall be grass itself, or that grass should be one of the vegetables. We must, for our requirement, select vegetables that contain as much nutriment in a given bulk as our present mixed diet, but in doing so we encounter the serious difficulty of finding that the readily soluble cell-wall or main bulk of animal food—the gelatine—is replaced in the vegetable by the cellulose, or woody fiber, which is not only more difficult of solution, but is not, nitrogenous—is only a compound of carbon, oxygen, and hydrogen.

Next to the enveloping tissue, the most abundant constituent of the vegetables we use as food is starch. Laundry associations may render the Latin name "fecula," or "farina," more agreeable when applied to food. We feed very largely on starch, and take it in a multitude of forms. Excluding water, it constitutes above three fourths of our "staff of life"; a still larger proportion of rice, which is the staff of Oriental life, and nearly the whole of arrowroot, sago, and tapioca, which may be described as composed of starch and water. Peas, beans, and every kind of seed and grain contain it in preponderating proportions; potatoes the same, and even those vegetables which we eat bodily, all contain within their cells considerable quantities of starch.

Take a small piece of dough, made in the usual manner by moistening wheat-flour, put it in a piece of muslin and work it with the fingers under water. The water becomes milky, and the milkiness is seen to be produced by minute granules that sink to the bottom when the agitation of the water ceases. These are starch-granules. They may be obtained by similar treatment of other kinds of flour. Viewed under a microscope they are seen to be ovoid particles with peculiar concentric markings that I must not tarry to describe. The form and size of these granules vary according to the plant from which they are derived, but the chemical composition is in all cases the same,