Abstract:

The effects of papain, alcalase, flavorzyme, pepsin, trypsin and neutral on the proteolytic activities of protein from the grass carp viscera were studied. Protein extracts were obtained by centrifugation. The molecular formula of protein was measured by SDS-PAGE.The results showed that the molecular formula of protein were 39.4KDa, 13.2KDa, 2.8KDa, respectively. The ammoniacal nitrogen contents in the hydrolyzates increased rapidly in the first 6 hours, then were stable. The peptide nitrogen contents reached the peak at the sixth hour for other protease except alcalase at the ninth hour. Ammonia nitrogen content of hydrolyzates were the highest for flavorzyme, and the differences were significant with each other except between alcalase and neutral. The peptide nitrogen contents of papain were higher than those by the other enzymes, while those by flavorzyme were the lowest. The taste of the hydrolyzates were constantly changing along with the enzymatic hydrolysis proceeded. As the release of amino acid and peptide, fresh flavor became notable. The umami of flavorzyme were significantly notable.