The lipid composition of frozen stored fillets from pre‐ and postspawned hake was studied. The total lipid (TL) content in the chloroform/methanol extract from unfrozen postspawned hake was four times higher than that of prespawned fish. After freezing, the TL content of postspawning hake muscle remained unchanged whereas the TL extracted from prespawning fish muscle increased about 90%. The TL extractability of muscle from fish in both different gonadal conditions was not affected by frozen storage. Lipolysis in frozen stored fillets from prespawned hake occurs principally by hydrolytic action on phospholipids (PL), and phosphatidylcholine was the main PL hydrolyzed. Triacylglycerols were the main substrates hydrolyzed in frozen stored fillets from postspawned hake. Freezing and frozen storage affected polyenoics and n‐3 fatty acids (FA). The decrease in the contents of n‐3 FA in fillets from postspawned hake was lower than that observed in fillets from prespawned fish.

Total, non-volatile free fatty acids (FFA) content was determined in hake muscle during fkh storage in ice. FFA increased linearly in every season according to freshness loss as determined by sensory scoring. FFA determination is proposed as a valuable alternative to sensory scoring in determining fkh deterioration in ice.

Protein solubility, reduced and intrinsic viscosity, and enzymatic activities of actomyosin showed that frozen fillets from pre-spawned hake, stored at Ϫ20ЊC, deteriorated faster than those from post-spawned hake. The post-spawned actomyosin showed an 18% increase in reduced viscosity, a larger hydrophilic surface, and an increase (PϽ0.001) in Mg 2+ -, Mg 2+ -EGTA-and Ca 2+ -ATPase activities. Protein solubilities of 85.5 ‫%5.2ע‬ and ‫%0.2ע33‬ were obtained at the end of storage for post and pre-spawned fillets, respectively. Enzymatic activities of post-spawned fillets persisted up to 60 days. No changes were detected in characteristic polypeptide bands of actomyosin or in the myosin/actin ratio related to either gonadal condition during storage.

The changes of free fatty acids (FFA) during the ripening of salted anchovy was studied. In the course of the curing process, the content of free fatty acids (FFA) in the muscle increased fifteen-fold, mostly in the first 100 days of the process. Each sample was subjected to sensory evaluations. A high correlation between FFA contents and sensory scores was found. Therefore the determination of FFA is proposed as an objective index to assess the ripening of salted anchovies.

The biochemical properties of actomyosin (AM) and lipid composition of the mantle from frozen‐stored whole squid were investigated. Irrespective of the sex of specimens, during the first months of storage, there was a trend of decreased protein solubility, reduced viscosity and enzymatic activities of AM. A significant decrease (P < 0.05) in the relative percentage of the myosin heavy chain and a significant increase (P < 0.05) in those of paramyosin and the 155‐kDa component were also observed. After freezing, phospholipids (PL), sterols (ST) and triacylglycerols (TAG) represented 38.6, 29.1 and 21.2%, respectively, of total lipids (TL) from the mantle of male squid. Free fatty acids (FFA) plus diacylglycerols constituted only 11% of TL. TL extract from the mantle of female squid had a higher percentage of PL and had lower ST. In the frozen‐stored male and female squid, TAG were hydrolyzed earlier than PL. At zero time of storage, the relative percentages of saturated and unsaturated fatty acid in TL extracts from the mantle of male and female squid were 39.1, 59.2 and 38.7, 61.1, respectively. Irrespective of sex, the saturated FA fraction significantly (P < 0.05) decreased and the unsaturated one significantly (P < 0.05) increased after 8 months of frozen storage.