ABSTRACT
Freezing food means reducing the temperature below the freezing point so that most of the water contained in the material turns into ice. The freezing point depends upon the concentration of different solutes in the tissue fluids. The lethal effect is higher in water and buffer solutions than in foods and increases due to repeated thawing and freezing. The changes in lipids are directly and indirectly responsible for the quality deterioration in frozen seafoods. Lipid oxidation in frozen stored seafoods is primarily nonenzymic in nature, although recently the involvement of microsomal enzymes and lipoxygenase has been reported. The choice of the freezing system to be used on board vessel or on shore for the given marine food is made with respect to quality of the final product, the capital requirements and cost of operation, as well as convenience, maintenance problems, and space limitations.
