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. Ca²⁺ 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.