ABSTRACT
The main edible portion of a marine animal is composed of the largest muscles of the body. However, many other parts are also used as food, especially the skin, liver, milt, roe, the fins of shark, and the alimentary tract of squid. The hydration of proteins is responsible for the rheological properties and juiciness of muscle foods. In tables of food composition, the content of proteins refers usually to the crude protein. Among the sarcoplasmic enzymes influencing the quality of fish as food are mainly the enzymes of the glycolytic pathway and the hydrolytic enzymes of the lysosomes. The nutritive and commercial value of various fish and marine invertebrates depends on the structure of the flesh and other edible parts, on the proportions of these parts in the total mass of the specimen, on the chemical composition of the meat, gonads, liver, etc., and on factors related to fishing and handling procedures.
