Proteolytic enzymes (proteases)

Proteolytic enzymes (proteases) are among the enzymes that play an important role in sake brewing. Produced mainly by koji (rice cultivated with koji mold), these enzymes break down the proteins in rice and produce amino acids, which contribute to the flavor and aroma of sake. There are two main types, acid protease and acid carboxypeptidase, and they break down proteins through different mechanisms. When proteolytic enzymes work properly, they improve the quality of the sake and are essential for bringing out umami.