Figure 1.

An overview of multiple processes for Sake brewing with sampling targets in the study. The group of Floor includes the brewery’s floor samples. The group of Raw materials includes water and Koji. The group of Equipments includes the wood board, wood stand, cloth, and tank for Moto Fermentation. 10 samples with grid lines were collected in this study. Sample collection was performed in duplicate. A fungus called Aspergillus oryzae, which is capable of secreting amylases, is cultivated on steamed rice to create Koji. This proliferated Koji, along with steamed rice and water, is then placed in an open-top tank to initiate the fermentation process and produce Moto. The starter is subsequently mixed with additional Koji, steamed rice, and water, and fermentation for a period of 3–5 weeks is done to make Moromi through three-step preparation (Sandan-jikomi). Moromi is separated into Sake and spent rice by a filter press.