Studies on Muscle of Aquatic Animals-XIV

Effect of Neutral Salts on Protein Denaturation

Abstract

The change in the degree of denaturation of protein occuring in fish muscle during the course of storage with various kinds of salts in different concentrations was investigated by measuring at suitable intervals the solubility of the protein at optimum concentrations of the same salts as used for the storage. As a result of this, it was found that the protein in muscle was most remarkably denatured when stored with salts of an ionic capacity of about 1.0 γ/2. We ascribed this result to the presence of an enzyme associated with protein denatured in such a method that its activity attains maximum under conditions of about 1.0 γ/2 ionic capacity.
The strength in the effect of the salts investigated on protein denaturation was in the following order: MgCl₂>NaCl>KCl>MgSO₄, this order was in accordance with that of their solubility capacity for the protein. Regarding this fact, probably there may exist a certain relation between the denaturation and solubility capacities of the salts used in the present work.
At any rate, in view of the striking effect of MgCl₂ on protein denaturation thus proved, it is positively desired for aquatic productions to apply bitter-brine-free salts.