Control of Rancidity in Fish Flesh: II. Physical and Chemical Methods

Abstract

Storage of frozen fish in high partial pressures of carbon dioxide or nitrogen effectively prevented fat oxidation and organoleptically detectable rancidity. Carbon dioxide stored fish developed an undesirable flavour not observed in that stored in nitrogen. Ice glazes formed from water or ethyl gallate solutions were about equally effective in delaying fat oxidation in frozen salmon steaks or fillets, but considerably less effective than 1-ascorbic acid or sodium 1-ascorbate glazes. Immersing salmon steaks or fillets in 1-ascorbic acid or sodium 1-ascorbate solutions strongly inhibited fat oxidation. 1-Ascorbic acid and closely related compounds were as effective, or more effective, than ethyl gallate or several other gallic acid derivatives for frozen fish. When 1-ascorbic acid was added to fish flesh its concentration fell rapidly at first, and then very slowly in the frozen fish.