Effects of rice-koji preservation condition and amazake salt concentration on protease activity

Abstract

Upon examining the degree of protein degradation in minced meat fermented with amazake at low temperature(5°C), the protein decomposition was found to be gentle. In order to clarify the effect of meat fermentation using amazake such as softening the meat faster, the preservation condition (refrigeration, freezing) of rice-koji and the salinity concentration of amazake was examined. The protease activity of rice-koji tended to increase with the preservation period for both refrigerated and frozen samples, and the frozen preserved rice-koji did not show significant deterioration. Upon adding sodium chloride to amazake, its protease activity increased at the enzyme reaction temperature of 55°C. Since it is considered that fermenting with amazake containing salt has higher versatility in cooking, it is necessary to clarify the effectiveness of adding salt at 5°C, which is currently the actual condition for meat fermentation.