抄録
Lipid alterations in jack mackerel Trachurus japonicus muscle during cold storage at 5° ?? -25°C were investigated by following the periodic decrease of C22:6 acid in each lipid (fractionated by the modified MCCARTHY and DUTHIE'S method).
Lipids were subject to hydrolysis by lipolytic enzymes and to oxidation. Generally, phospholipid (PL) underwent considerably more severe hydrolysis and oxidation than neutral lipid (NL), and oxidation of free fatty acid (FFA) was the most severe. These findings indicated that enzymatic hydrolysis of PL and NL plays a significant role not only in FFA formation but also in the oxidation of FFA. Moreover, it was perceived that this pattern of lipid alteration had no correlation to the lipid content of muscle nor to the positional difference of muscle.
Reducing the temperatures of storage effectively inhibited lipid hydrolysis and oxi-dation, and at -25°C hydrolysis and oxidation of PL were preferentially inhibited while mild oxidation of FFA took place.
