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Biochemical and physicochemical properties of natural actomyosin (NAM) from pre-and post-spawned hake stored on ice were studied. At the beginning of storage both reduced viscosity and ATPases activities of NAM from post-spawned hake were about 3 times higher than those of the pre-spawned ones, except for the Mg2+-(Ca2+)-ATPase. Higher loss of functional components during pre-spawned hake NAM purification was found compared to NAM from postspawned fish. Reduced viscosity and Mg2+-(EGTA)-ATPase activity of NAM from both pre-and post-spawned hake decreased following ice storage. SDS-PAGE patterns of NAM from pre-spawned hake showed an absence of the myosin heavy chain and the presence of a 160 kDa component at zero time of storage. No proteolysis occurred in ice-stored fish caught in both gonadal stages.

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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.