Post-Mortem Tenderization of Fish Muscle due to Weakening of Pericellular Connective Tissue.

Abstract

To determine the structural change involved in the post-mortem tenderization of fish muscle, histological study was performed for yellowtail, flatfish, red sea bream, and tiger puffer. After decapitation, each fish was stored at 5°C and the change in breaking strength was measured. Histological observation was performed by using a light microscope for the stored muscles after compression at 100g/cm2 for 10sec. Muscle tenderization was demonstrated for yellowtail, flatfish, and red sea bream, but not for tiger puffer. Detachment of muscle fibers by compression was observed to be dependent on the storage time for yellowtail and flatfish. In the case of red sea bream, the compression condition employed in the present study was so strong that the detachment of muscle fibers were demonstrated even immediately after death. In contrast, in the case of tiger puffer, detachment of muscle fibers after compression was hardly observed 72h after death. These results suggest that the weakening of the pericellular connective tissue detected by compression causes tenderization of muscles during chilled storage.