Bouillons are made by soaking finely cut meat for a time in water so that the extractives, the salts, and a little gelatin may be dissolved out. It is then slowly heated and cooked and finally brought quickly to a boil. When the liquid is poured off, it is rich in meat flavor, but contains little nutriment. If it is allowed to cool, fat will accumulate upon the surface. This should be skimmed off. The remainder will be found to consist of two layers - the upper and thicker of clear fluid, the lower of a turbid fluid. The turbidity of the latter is due to minute particles of coagulated albumin, which is almost the only nutrient material in it. If a clear bouillon or soup is prepared, this is strained off. The liquid that is swallowed contains only a minute amount of protein. Although it is not nutritious to an appreciable extent, it is agreeable to the taste, often whets the appetite, and promptly stimulates the secretion of gastric juice. It is, therefore, an excellent introduction to a more solid meal. If soup is to constitute the chief dish at a meal, it should be made more nutritious by the addition of vegetables or cereals or by stirring into it an egg. From such a thick soup the particles of coagulated albumin should not be strained off as they are when a clear bouillon is made.

Beef-tea, mutton broth, chicken broth, and similar preparations so frequently given to invalids are bouillons and especially poor in nutrient ingredients. They should be used only to whet the appetite and to act as feeble stimulants. When sipped as hot drinks, as coffee, tea, and even hot water, they will make the heart beat stronger and faster. The salines that broths contain are sometimes useful. The extractives or flavorings are not nutritious. They are mostly waste-products that are eliminated by the kidneys during the life of animals, and if they are eaten, must similarly be gotten rid of by man. They may thus in some cases act partially as diuretics, but under some conditions of renal failure may become toxic.

Beef-extracts, such as Liebig's, are concentrated bouillons, and when eaten, are diluted to the consistence of broth. Their composition and value are the same. Liebig's extract contains approximately 30 per cent, of protein and gelatin. When made into beef-tea, a pint of the latter will contain less than thirty grains of these ingredients. The experiment of starving one set of animals and of feeding another upon beef-extract has been made, with the result that both died in the same length of time. So thoroughly are medical men convinced of the insignificant food value of bouillons and beef-extracts that it is hardly necessary to emphasize the fact. They are still, however, household panaceas.

Beef-juice is made at home by lightly broiling a thick, juicy steak, cutting it into fine pieces, and squeezing it in a lemon-squeezer or, better, in a meat press. The extractives, the blood, and some of the proteins of the meat are thus extracted. Round steak can be made to yield nearly 7 per cent, of coagulable protein. If finely chopped raw meat is heated in a bottle kept for two or three hours in hot water, from 2 to 3 per cent, of coagulable protein can be extracted. Care must be taken not to boil the juice or heat it greatly, or the albumin in it will coagulate and will be precipitated. The commercial beef-juices, such as Valentine's, Wyeth's, and Armour's, are made by subjecting chopped meat to a strong pressure. The juice that is thus obtained is concentrated in vacuo to prevent coagulation of its protein. These preparations contain from about 2 to 30 per cent, of protein; most of them, from 4 to 5 per cent.

The following table of commerical extracts will give information as to the percentage of nutrients and some other important ingredients:1

Solid Meat Extracts

Fluid Meat Extracts

Miscellaneous Preparations

1 Compiled from Bulletin No. 114, Bureau of Chemistry, U. S. Department of Agriculture

White of egg contains 12 per cent, of egg-albumen. It is, therefore, much more nutritious than most of these juices and much less expensive. Meat juices have, however, both a positive and a negative value. Like bouillon, they often whet the appetite of invalids and excite the stomach to greater work. When bread, crackers, or rice are soaked in them, they make an agreeable dish and one that is nutritious. They should, therefore, be regarded as adjuncts to more nutritious food, and not as staple articles of diet. Their negative value in those cases of illness in which food must necessarily be withheld for a time, is that they permit 'nourishment' to be given that satisfies the family and does not materially harm the patient. Their use as temporary stimulants will be set forth in another connection.

Meat powders of various kinds are upon the market and are more or less useful to strengthen or increase the nutritive value of other foods. Beef powder can readily be made by drying boiled beef upon a water-bath and powdering it in a coffe-mill. The powder thus made can best be given in chocolate or milk. It is useful when it is necessary to administer food in a concentrated condition.

Mosquera's beef meal is a powdered beef that has been partly digested by pineapple juice. Somatose consists chiefly of albu-moses. A variety of 'peptone' preparations in powder form, or predigested powdered meat, are upon the market. Some of them are also offered in liquid form with and without alcohol. The following analyses of certain preparations tabulated by Hutchinson make plain the general nutritive value of the class:

Carnrick's peptonoids consist chiefly of starch and milk-sugar. Meat jellies are agreeable, especially during convalescence from illness, and are slightly nutritious. Their basis is gelatin. Glue is a crude form of gelatin. Its purest form is isinglass, which is obtained from the swim-bladders of fishes. The connective tissue of young animals is especially rich in it. Calves, feet when boiled yield 25 per cent, of gelatin and a little more than 11 per cent, of fat. Gelatin jellies, whether flavored with meat, fruit, or wine, rarely contain more than 2 per cent, of it. Gelatin is very soluble and easy to digest. It is not, as was explained in a former chapter, a builder of tissue as are proteins, but it possesses about the same power to produce energy. It is a protein sparer - that is, it prevents protein waste. It is estimated that it will save half its weight of tissue protein. It has been calculated that not more than twenty-five or thirty grams of gelatin can conveniently be taken in a day, and rarely more than a small fraction of this is eaten. If the former quantity were taken, it would effect a saving of only a little more than an ounce of flesh. Its value in fevers as a protein saver is therefore slight.

Fish is an economic kind of protein food. It is for the most part easy of digestion. The fat fishes, such as salmon, are less digestible than those whose flesh is of shorter, smaller fiber and less rich in fat. Fish is highly nutritious, but because it contains more water than most other meats it is weight for weight of less nutritive value. Lobster and crab meat are relatively indigestible because they are coarse and tough.

The oyster is the most highly prized shell-fish. When raw, it is more digestible than when cooked. It is nutritious and wholesome unless, as in some cases, contaminated with typhoid bacilli. It contains about 6 per cent, of nitrogenous matter, 1.5 per cent, of fat, and 3.3 per cent, of glycogen. A dozen oysters contain only about one ounce of solid matter. They therefore contain nourishment in a very diluted form and are not an economic food.