Fish and marine invertebrates are important sources of nutrients for the world's population, and many species have exceptionally high market value because of their exquisite sensory properties. Both the utilization of the available catch in different forms and the market price are affected by the quality of the fish. Proteins and nonprotein nitroge- nous compounds playa crucial role in the nutritional value and sensory quality of seafoods as well as in the suitability of different species to various forms of processing, preservation, and use in other branches of the food industry. This role...