Meat quality of frozen hybrid mackerel (Scomber australasicus × Scomber japonicus)

Frozen sashimi can be stored for a long time and transported over long distances, giving it a distinct advantage over fresh sashimi, and a stable supply of material for frozen sashimi products can be obtained using cultured fish rather than natural resources fish. Hybrids of blue mackerel Scomber australasicus and chub mackerel Scomber japonicus possess unique characteristics that are advantageous in aquaculture, such as a high temperature tolerance. To evaluate the quality of the meat in these hybrids after freezing, we compared the muscle properties of hybrid and chub mackerel that had been reared in a land-based tank. The hybrid mackerel had a lower gonadosomatic index and a higher crude lipid content than the chub mackerel. However, there were no significant differences in the breaking strengths of unfrozen and frozen–thawed muscles between the hybrid and chub mackerel. These findings suggest that the hybrid mackerel may be suitable for use in frozen sashimi products, and that it has unique characteristics that will give it added value as a branded fish.