Impacts of deep-sea aging on quality of greater amberjack (Seriola dumerili) and bluefin tuna (Thunnus orientalis) meats

This is the first report on the effective utilization of the deep sea for improving food quality. Long-term aged fish has recently received substantial attention because of improved taste quality and the sustainable utilization of fishery resources. However, problems such as the refrigeration energy and space limitations for aging remain. Therefore, effects of deep-sea aging at a 2034 m depth for 34 days on meat quality of greater amberjack and bluefin tuna were investigated with a focus on changes in taste components and texture. Our results showed that free amino acid (FAA) contents in the deep-sea-aged greater amberjack were higher than those in the laboratory-aged sample. The deep-sea method promoted the proteolysis involved in FAA generation and mitigated the degradation of inosine-5'-monophosphate in greater amberjack. Conversely, deep-sea aging did not improve the quality of bluefin tuna. The present study also showed that the increase in the total viable bacteria count could be suppressed in greater amberjack during deep-sea aging. Thus, the deep sea can be utilized for sustainable aging of fish with superior quality, even though its suitability might depend on the fish species and depths related to the pressure level.

Automated summary

This study provides the first report on the effective utilization of the deep sea for improving food quality. The results suggest that deep-sea aging can promote proteolysis and enhance the quality of fish such as greater amberjack, while its effectiveness may vary depending on fish species and depths.