Effects of bleeding on post-mortem changes in the muscle of horse mackerel [Trachurus jaonica]

The changes in rigor index, breaking strength, and the concentrations of energy-related compounds during ice storage of the dorsal muscle were investigated for horse mackerel killed by stabbing in the spinal bulb only or by that followed by bleeding. The rate of progress of rigor-mortis in the bleeding group was slower than that in the stabbing group without bleeding. No significant differences were observed in the changing rates of breaking strength, and concentrations of ATP and creatine phosphate until 36 hours after death. K-value from 3 days to 7 days after death had a tendency to be lower in the bleeding group. From these results, it was considered that the bleeding was a useful method for delaying the progress of rigor-mortis.