1Shimane Prefectural Fisheries Technology Center, Hamada, Shimane 697-0051, 2Shimane Prefectural Matsue Regional office of Fisheries Affairs, Matsue, Shimane 690-0011, Japan
We examined the best procedure for the handling of Japanese Spanish mackerel caught by shipboard angling. The mackerel were killed using four different procedures: stabbing the spinal bulb, bleeding out, killing by ice-seawater, and struggled suffocation. Breaking strengths of stabbed spinal bulb samples were greater than those of the other groups, while the extent of muscle tearing was less than those of the other groups. Muscle tearing in the struggled suffocation group was greatest among all groups. However, K values and lactic acid concentrations were independent of the killing method. These results indicated that stabbing the spinal bulb can delay the loss of breaking strength of muscle and prevent muscle tearing.