FoodNet

Foods, their selection and preparation

1935

Page 158

Presented as published in 1935. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
There are two kinds of connective tissue, white, which contains collagen, and yellow, which contains elastin. White connective tissue is insoluble in cold water, but if heated at 160° to 190° F. the collagen present is changed into gelatin, which is readily soluble in warm or hot water. Since white connec¬ tive tissue can be softened by regulation of the method of cooking, it may be said to con¬ tribute to "temporary toughness” in meat. Yellow connective tissue is insoluble at ordinary cooking temperatures. It is sof¬ tened only by treatment in superheated steam or by boiling with strong acids. It may, therefore, be described as contributing to permanent toughness in meat, tough¬ ness which is not improved by cooking but only by chopping, or grinding, or by remov¬ ing the yellow fibers. The proportion of these two types of connective tissue varies in muscles from dif¬ ferent animals and from different parts of the same animal, depending upon the cut. [171] The total amount of connective tissue varies with the extent to which the muscle has been used, the way the animal has been fed, and its age. Color of Meat. The pigment hemoglobin and related pigments are responsible for the reddish color in meat. Hemoglobin is found in the blood left clinging to the walls of the capillaries, arteries, and veins. Other pig¬ ments are a constant constituent of the mus¬ cle plasma. The amount of these varies in different muscles in the same animal, and in the same muscle in different animals. This variation may be due to breed, kind of feed, age, amount of exercise, or to a combination of these and other factors. Beef muscle is dark in color when it is first cut across its fibers. If the freshly cut surface remains in contact with the oxygen of the air, the hemoglobin is oxidized to oxy¬ hemoglobin, producing a bright-red color. The brightest color is usually attained after about an hour’s exposure to the air. Grass- fed beef is darker than corn-fed. The color of the lean also varies with the different kinds of meat animals. Veal is pink to very light red and mutton is darker than lamb. Pork from old hogs is darker than that from young. Lamb is a darker red, however, than beef, and pork and veal are the lightest in color. Fat. Animals store their excess energy in the form of fat deposited in certain cells of the connective tissue. When a group of these cells are filled with fat, the connective tissue becomes fatty tissue. The deposition of fat in these small cells stretches the walls thin, so fatty tissue tends to be tender. The amount and distribution of fat vary with the type and breed of animal and with the plane of nutrition. The main fat depots are in the connective tissue around internal organs, around and between muscles, and directly under the skin. The color and melting point of the fat