凍結および貯蔵によるマサバ筋原繊維タンパク質の変性

Abstract

During freezing and subsequent frozen storage of fish muscle, the denaturation of myofibrillar protein was studied by measuring the inactivation of its Ca-ATRase activity Minced muscle of chub mackerel (and sardine) was initially frozen at -20, -30, or -40°C for 20 h and stored at -20, -30, or -40°C for 8 months; the denaturation of myofibrillar protein becameless for lower temperatures of storage, regardless of the initial freezing temperature The whole fish of chub mackerel was frozen at -40°C for 20h and stored at -20, -30, or -40°C for 4 months. Frozen surimi was then prepared and its myofibrillar protein and kamoboko forming ability were evaluated. The quality of surimi was found to be improved for lower temperatures of frozen storage. When the minced muscle (A) of chub mackerel, which has previously been treated with 0.3% NaCl twice (B) or with 0.5% NaHCO3 followed by 0.3% NaCl (C), was frozen at -40°C for 20h and stored at -20, -30, or -40°C for 4 months, a similar relationship between the temperature and the denaturation of myofibrillar protein was also recognized, but the extent of denaturation of (B) was considerably larger than that of (C). The addition of 5% sucrose to the treated minced muscle effectively prevented its denaturation by frozen storage.