Hogg's Protein Nerve Food is practically the same as sanatogen. Sanose. This is a powder. It contains 80% of pure casein and 20% of albumose obtained from the white of egg. The powder possesses a slight taste and an odor suggestive of milk. By briskly stirring the powder with water, an emulsion may be made much resembling milk, but on standing it soon breaks up. Sanatogen is a grayish-white, tasteless powder, containing 95% of casein and 5% sodium glycero-phosphate. When treated with cold water it swells, forming on heating a milk-like emulsion. Vitafer and Cibrola are similar to sanatogen but contain more glycerophosphate and less casein. Lactalbumin in dried and powdered form, like lactose, is obtained from whey. CHAPTER VIII. FLESH FOODS. MEAT. General Structure and Composition. Meat is structurally made up of muscle fibers, held together by connective tissue, through which blood vessels, nerves, and usually fat cells are more or less abundantly distributed. Each muscle fiber has a sheath or covering known as sarcolemma inclosing the meat juices, which are solutions in water of proteins, non-protein nitrogenous extractives, and salts. The insoluble portion of the living muscle (connective tissue, sarcolemma, etc.) is known as stroma, the soluble portion constituting about 60% by weight as obtained by high pressure, as plasma. After rigor mortis sets in certain soluble constituents coagulate and the liquid obtained by pressure is a serum analogous to the serum separated from blood clot. Nitrogen compounds constitute by far the most abundant and important portion of the substance of lean meat. Carbohydrates are almost entirely lacking, the small amount of glycogen and muscle sugar together constituting rarely more than 1 per cent. The Nitrogenous Substances consist of proteins and so-called extractives. The stroma proteins include the elastin and collagen of connective tissue and the proteins of the sarcolemma which are imperfectly understood. Formerly myosin, a globulin-like substance, was considered the chief protein of the plasma but now it is believed that myogen, an albumin, is a more abundant constituent. Peptones and proteoses are formed in meat after death by enzymic action. The extractives of chief interest to the analyst are creatine, creatinine, carnosine, carnitine, methyl guanidine, and the purine bases xanthine, hypoxanthine, guanine, and adenine. The Fats are considered in Chapters III and XIII. Carbohydrates. Glycogen (C6H1005), sometimes called animal starch, is a white, amorphous, tasteless, and colorless substance, when pure, much resembling starch. It is soluble in water, forming an opalescent solution, and is insoluble in ether and nearly so in cold alcohol. With iodine a port-wine color is produced, which disappears on heating and reappears on cooling. Glycogen is strongly dextro-rotatory and converted into dextrose by boiling with dilute mineral acid. It occurs in small amount in all fresh muscle, particularly that of the horse, and in larger amount in liver, but disappears to a large extent on aging. Muscle Sugar is either entirely absent in the living muscle, or exists in traces only. After death it is formed presumably from the glycogen, and exists in a very minute quantity, probably as dextrose. Inosite (C6H12O6+H2O) is found in traces in the muscular substance and animal organs. It is a protoplasmic substance related to the carbohydrates. The Acids developed in meat consist chiefly of lactic. Succinic, inosinic, and uric acids are among the other acids present in small amount. The Ash of meat consists, like that of plants, of phosphates, sulphates, and chlorides of potassium, sodium, calcium, magnesium, and iron together with traces of other inorganic constituents. In the meat itself some of the inorganic elements exist in organic combination. The approximate proportions in which the chief constituents are present in meat is thus shown by König: Water.. Nitrogenized compounds.... Fat.... 75.0 to 77.0 Other nitrogen-free compounds..... Formic acid.. Proximate Composition of the Commoner Meats.-The chief characteristics of the flesh of various animals are in the main very similar, whatever the nature of the animal. So true is this, indeed, that it is usually impossible from a chemical analysis to distinguish a particular kind of flesh when mixed with that of other animals in finely divided meat preparations, such as sausages, potted and deviled meats, and the like. The average composition of the commoner cuts of beef, veal, mutton, lamb, and pork, as well as of fowl and game, is shown in the following tables, compiled from the work of Atwater and Bryant *, the accompanying diagrams serving to locate, in the case of ordinary meats, the portion of the animal from which the meat is taken. Constants of Fat.-These as found by Bigelow are given in the table on page 212. Characteristics of Sound Meat.-The reaction of meat should be acid. If neutral or alkaline, decomposition is indicated, except that alkalinity may be due to the use of alkaline salts as preservatives. Letheby† gives the following characteristics of sound, fresh meat. In color it is neither pale pink nor deep purple, the former indicating that the animal was affected with some disease, and the latter that it died a natural death, and was not slaughtered. In appearance it is marbled, due to the presence of small veins of fat distributed among the muscles. In consistency it is firm and elastic to the touch, and should hardly moisten the finger; a wet, sodden, or flabby consistency with a jelly-like fat is indicative of bad meat. As to odor, it is practically free; whatever odor there is should not be disagreeable; a sickly or cadaverous smell is indicative of diseased meat. After standing for a day or so, it should not become wet, but on the contrary should grow drier. When dried at 100° C. it should not lose more than 70 to 74 per cent in weight; unsound meat frequently loses 80% or more. It should shrink very little in cooling. Inspection of Meat.-While carefully drawn laws exist almost everywhere relating to the sale of meat, and government inspectors are appointed to carry out the requirements of the laws, yet in this country there is undoubtedly some meat unfit for food on the market, owing to the small number of inspectors, and the consequent comparative safety with which unscrupulous dealers may sell meats forbidden by law and escape detection. The inspection of meats and fish under municipal ordinances is not always carried out as thoroughly as might be desired. * U. S. Dept. of Agric., Off. of Exp. Stations, Bul. 28 (Revised Ed.). Fat Medium-edible portion.. 15 55-5 Loin: Lean as purchased.. edible portion.. 12 as purchased... II Medium-edible portion.. 32 13.1 Fat as purchased... 32 13.3 as purchased... 6 10.2 49.2 Rump: Lean edible portion.. 4 as purchased... 3 14.0 Medium-edible portion.. 10 Fat 20.8 43.8 48.5 15.0 15.2 35.6 16.8 39.6 12.7 12.4 30.6 0.6 1525 67.0 19-7 19.3 12.7 1.0 900 58.2 17.1 16.7 II.I 0.9 785 60.6 18.5 18.2 20.2 52.5 16.1 15.8 17-5 0.9 54-7 17.5 16.8 27.6 0.9 1490 15-7 15.0 24.8 0.8 65.7 20.9 19.6 13-7 1.0 56.6 19.1 17-5 II.O 56.7 17.4 16.9 25-5 as purchased... 10 20.7 45.0 13.8 13-4 20.2 0.7 edible portion.. 5 47.I 16.8 16.4 35-7 as purchased... 5 23.0 36.2 12.9 12.6 27.6 17-5 17.0 70.0 21.3 21.0 7.9 I.I 730 670 I.I 950 895 as purchased... 53 3 12.0 60.4 19.5 19.1 19-5 1.0 1185 1005 |