PROBLEM TO BE SOLVED: To provide a method of manufacturing an oyster extract that can control the secretion of leptin and insulin.SOLUTION: The method of manufacturing an oyster extract includes: a heat treatment process in which a solution in which oyster meat and water are mixed is performed with a heat treatment process at a temperature of 90±3°C a proteolysis process in which the pH of a processing result object of the heat treatment process is adjusted by the pH of 8-9, then the processing result object is added with a protease of a Bacillus licheniformis origin, Bacillus subtilis origin, Bacillus sp. origin, or Bacillus clausii origin at a temperature condition of 60±3°C, and a protein included in the oyster meat is performed with enzyme decomposition a deactivation process in which a processing result object of the proteolysis process is heat-treated at a condition of the pH7±0.3 to deactivate the protease and a separation and concentration process in which a processing result object of the deactivation process is separated to an extract component and a waste component, then the extract component is concentrated to obtain the oyster extract.
