Biochemical and Functional Properties of Myofibrils from Preand Post‐Spawned Hake ( Merluccius hubbsi Marini ) Stored on Ice

Enzymatic activities assayed at beginning of storage in myofibrils from post‐spawned hake were 3 X those in myofibrils from pre‐spawned hake. Ca 2+ sensitivity of myofibrils from pre‐spawned hake was 40% less than that of myofibrils from post‐spawned hake. The profiles of SDS‐PAGE gels of pre‐spawned myofibrils at beginning of storage showed a partially denatured myosin heavy chain, and polypeptide bands under myosin heavy chain. They probably represent proteolytic fragments produced by degradation of MHC in vivo . No proteolysis was detected in myofibrils during storage. These results help predict functional properties of fish proteins and changes during storage.