Elements of the theory and practice of cookery

345. Butterine or oleomargarine is made from the olein (oily part) of purified beef and pork fat churned with milk, mixed with butter, and salted and colored as butter is. Good butterine contains about 25 per cent of butter, 30 per cent of " neutral," or lard oil, 25 per cent of olein from beef, and 20 per cent of salt and cream. It is clean, pure, wholesome, and nutritious, and so like good butter that no one eating it can tell the difference. Being cheap to make, it should be sold cheap ; but un- reasonable laws, designed to prevent its being sold as butter, keep it almost altogether out of the market, while bad butter is openly sold for far more than it is worth. For an account of butter and butter-making, see pp. 97-99 ; for lard and other animal fats see section 2 of Chapter VI. 214 THEORY AND PRACTICE OF COOKERY 346. ^QQ^B, particularly nuts and grains, are rich in oil^ some containing 50 per cent or more, stored up, as starch is, to feed the seedling. Fat as Food 347. Fat as food; no diet well-balanced without it. — Knowing fat to be a heat giver, we can understand why we like, in winter, foods containing more fat than we care for in summer, and why arctic explorers come to like whale-blubber and walrus fat. But when we learn that the natives of even tropic India pour melted butter (ghee^ over their rice, we perceive that in any climate, and under all conditions, men need to eat some fat. In a body poorly supplied with this, its proper fuel, pro- teid has to take its place. But proteid is costly, is needed for tissue-building, and, besides, is worth less than half what fat is as a heat giver. So that in burn- ing proteid to keep up our bodily heat, we are like people who, storm-bound on the prairies and out of fire- wood, feed their stoves with furniture and even with grain ; that is, we use for fuel, material intended and needed for other purposes, and which we can ill afford to burn. Girls often dislike fat, particularly the thin, delicate ones who most need it. If possible it should be offered to them in tempting and digestible forms, cream salads dressed with oil, and crisp, fat bacon. But all kinds of fat can be so prepared as to be unobjection- able. Some ways of using it, however, are harmful to health. To see why this is we must understand some- thing about the digestion of fats. FAT FROM ANIMALS AND OIL FROM PLANTS 215 348. How fat is digested. — Fats undergo much less change in the alimentary canal than either proteids or carbohydrates. They pass out of the stomach, indeed, in practically the same state that they entered the mouth. Even in the small intestine they are not dissolved, but are in part emulsified and in part saponified (turned to soap) by the pancreatic juice, bile, and intestinal juice. In this process the fat is divided into smaller and smaller droplets, till these become tiny enough to be sucked up by cells lining the intestine. From these cells the fat is passed on to the lacteals, fine tubes joining eventually in one large one, the thoraeie duct, which empties into the blood streams. In these it is always found in the form of an emulsion, the milkiness caused by the sus- pended globules giving these little tubes their name (§ 174).