The Romance of Modern Chemistry

FATS AND OILS The process most in vogue for obtaining animal fats and oils is known as “rendering”; the fatty matter is boiled with water or steamed, and the oil which floats on the surface is removed. In this way it is obtained free from adhering tissue. Attention was drawn in the previous chapter to the fact that fats are one of the principal constituents of human food. Butter, lard, suet, olive oil, and cocoa butter may be mentioned as fats which are used either directly as food or in the preparation of dishes for the table. In this country we import over ^20,000,000 worth of butter alone per annum, in addition to the butter made and consumed at home. Butter, however, is not the only fat which is used directly as human food. Margarine, an artificial mixture of animal fats, with possibly a small amount of vegetable fat, is manufactured in large quantities nowadays, the annual consumption in this country being estimated about .£5,000,000 worth. Its manufacture dates back to the time of the Franco-German war, when the inhabi- tants of Paris were hard up for butter. This fact would seem to indicate that margarine is to be used only by those who are reduced to their last resources, but really no reasonable objection can be taken to this material when made under satisfactory conditions and sold under its own name. A member of Parliament, referring on one occasion to margarine, spoke of “all the greasy rubbish of the world which is being dumped down in this country ; but this description is now quite out of date. Other edible fats turned out in large quantities are the so-called vegetable butters, which are valued by our vegetarian friends, and appear in the market under all sorts of fancy names. In India, where, on religious 239