Rancidity in Lean Fish Muscle.: IV. Effect of Sodium Chloride and Other Salts

Abstract

Sodium chloride accelerated rancidity in blended cod muscle at 0 C. This salt-induced rancidity was retarded by commercial antioxidants and chelating compounds. The active agent appeared to be the Na+rather than the whole salt or the Cl−.Other metal salts had similar pro-oxidant action on the cod muscle when used in relatively high concentrations (0.1 N and above). The relative activity, using metal chlorides, was as follows: Fe > Co > Cd > Li > Ni > Mg > Zn > Na > K. Ca and Ba had no effect.Many of these "pro-oxidant" salts also had a strong antioxidant effect on the development of copper-induced rancidity in the muscle.The relationship between TBA values and the type and intensity of odours is not the same for sodium chloride-induced and copper-induced rancidities. Some of the reasons for this have been discussed.It has been suggested that one mechanism by which sodium chloride influences the rate of lipid oxidation in the fish muscle is by the changes it produces in the accompanying proteins.