Preparation of Seasoning with Shrimp-like Flavor from the Aqueous Residue of Isada Krill under Subcritical Water Conditions

Conditions were examined to prepare a seasoning with shrimp-like flavor from the aqueous residues formed after the recovery of oil-soluble functional components in Isada krill caught from the Sanriku coast in 2017 and 2018 upon treatment under subcritical water conditions. Treatment at 160 ℃ increased the amount of insoluble material and decreased the concentration of soluble matter. The color of the aqueous residue depended on the year of the catch, and the color after treatment under subcritical water conditions was also different. However, when treated under subcritical water conditions, both aqueous residues obtained from the 2017 and 2018 catches showed a decrease in the fishy odor and an increase in fragrant and burnt aromas. The preference score obtained for the residue obtained from the 2017 catch increased after the treatment process. On the other hand, the aqueous residue obtained from the 2018 catch, which did not show any improvement in the preference score upon treatment, was improved when diluted 2 or 4 times after the treatment process. GC-MS analysis revealed that pyridines and pyrazines related to shrimp-like flavor were produced in both aqueous residues obtained from the 2017 and 2018 catches upon treatment under subcritical water conditions.