筋原繊維タンパク質とソルビトールなど添加物の濃度が冷凍変性に及ぼす影響

Abstract

The protective effect of some additives, such as sorbitol, Na-glutamate, and Na-acetate against freeze denaturation of carp myofibrillar protein was investigated by measuring change in first order rate constant (kD) for inactivation of its Ca-ATPase as a function of protein con-centration (M) for frozen storage with additive. Myofibrills were mixed with either one of the above mentioned additives in a medium of 0.16M KCl, 40mM Tris-maleate (pH7.5)to give the final concentrations of additives and myofibrillar protein between O-0.24M and 2-20mg/ml, respectively. During frozen storage, decrease in myofibrillar Ca-ATPase activity was measured with a laspe of time and the kD was calculated. It was thus found that the kD of the mixture were almost identical where the molar concentration of each additive was kept the same but that of myofibrillar protein however varied considerably. From the results mentioned above, a possible mechanism for the protection of freeze denaturation of myofibrillar protein by sorbitol, and the like, was discussed.