Alterations in the texture and protein; the free amino acid contents of fish meat with miso and sake lees

Abstract

We investigated alterations in the quality of misozuke and sakekasuzuke prepared with sablefish, traditional processing and cooking methods whereby fish meat is cured in miso or sakekasu (sake lees), respectively. SDS-PAGE patterns of the fish meat revealed protein decomposition during preservation by the enzymes present in miso or sakekasu. We analyzed the levels of free amino acids in sablefish misozuke and sakekasuzuke using an amino acid analyzer. The amino acids found in miso and sakekasu permeated the fish meat and altered the amino acid composition, significantly increasing the umami amino acid content. Further, the meat texture was measured using a creep meter. While the texture of cooked misozuke fish was very firm; less firm than that observed in heated sakekasuzuke. It is proposed that the fish flavor and palatability can be explained by the synergistic effects between miso or sakekasuzuke and the unique fish flavors.