Enzyme powder is prepared from internal organs of fish as follows: fresh pyloric coeca containing much protease is crushed with sand in the mortar, water is added, enzyme is extracted, and clear extract is obtained by filtration or centrifugation. After, Japanese acid clay is added to this solution, clay is separated by centrifugal separation and dried in a desiccator. The enzyme can be eluted from this prepared clay by slightly alkaline buffer solution.
