This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
The composition of beef varies with the feeding of the animal. A young steer from two and a half to five years old furnishes the best meat. If the animal is lean the meat may yield from 70 to 75 per cent of water and about 20 per cent of nitrogenous material, furnishing about 415 calories per pound, with 2 or 3 per cent of fat; but if very fat when killed, the percentage of both water and nitrogenous material is considerably reduced, while that of the fat may be as high as 25 per cent, or even more. As a general average, one third of beef is nutritious material, the remainder is water and bone.
Beef fat is composed of glycerides of fatty acids. It melts at from 41 ° to 500 C. Stearic and palmitic acids are present in the proportion of three to one of oleic acid.
The equivalent of beef is sometimes stated in terms of other foods. A pound of lean beef is believed to equal in nutrient value two and a half pints of milk, half a pound of bread, and about three eggs, but these are only approximate figures.
Fresh beef can be eaten longer continuously than any other kind of meat. In this respect it resembles bread and rice. Attempts have sometimes been made on wagers to eat quail or partridge three times a day consecutively for a month, but disgust is sure to follow after a week or two, no matter how much such food is varied in the cooking, and by the end of a month it may excite extreme loathing, and even nausea and vomiting.
Chipped beef is prepared, like corned beef, by pickling for a month, when it is smoked for two days and dried for a fortnight, after which it is sliced thin by machinery and is ready for packing.
Beef is so important a food for well and sick alike that many attempts have been made to improve its digestibility for the latter.
Most of these efforts are aimed at concentrating the meat by removing all indigestible connective-tissue fibre, the muscle sheaths, sarcolemma, and blood vessels.
In some cases the process of concentration is carried still further and water is driven off by evaporation, or some of the active principles of the meat are extracted and condensed. Sometimes the meat is predigested. Different meats may be prepared in these ways, but the best lean beef free from coarse fibre is usually preferred.
It is impossible within the limits of this work to even name all the meat extracts, powders, etc., that have been produced, but a few of the typical ones which are most in use will be described below.
It was long ago shown by Schiff that many fluid substances, such as meat extract, soups, peptones, and even vegetable purees when taken at the commencement of a meal, on being absorbed into the blood, favour the flow of gastric juice. This is true also of peptones injected into the rectum, so the effect is not wholly due to local stimulation of the inner surface of the stomach.
Much attention has of late been given to the predigestion of meat, and especially to the production of albumoses, which are more soluble and assimilable than undigested meat albumin, and which are said to possess greater nutritive property than peptones.
The beef extracts made in this country usually have a less disagreeable taste and odour, and are lighter in colour than those made of South or Central American beef.
In general, about three grammes of meat extract constitute a good soup ration, and such preparations are often valuable for addi-tionjio invalid soups and broths when thickened with eggs, rice, sago, pearl barley, macaroni, ground toast, etc.
The preparations of meat for the sick are both solid and fluid.