Recovery of amino acid from the protein in the head and viscera of frigatemackerel by autolysis

The digestive conditions were investigated to recover amino acids and pepti des from the protein by autolysis from the viewpoint of the effective utili zation of the wastes of frigate mackerel. Protein in the head-viscera mixture was efficiently and easily autolyzed at 15 degrees C for 24 h at neutral pH. Eighty-seven percent of protein in th e mixture were recovered as extractive nitrogen and the autolytic extract o btained was rich in free amino acids and peptides. The hot water extract ob tained from the autolyzate had umami taste. These results suggested that th is autolytic extract can be used as a seasoning material.