Application of fuzzy control theory to the sake brewing process

Abstract Know-how of skilled operators concerning the management of the traditional sake brewing process was analyzed using fuzzy control theory, and arranged as production rules having the following four fuzzy variables: if (DB = DBi) & (DD = DDi) & (AL = ALi) then (CT = CTi). Membership functions of DB and DD were arranged in real-time using a kinetic model proposed by us previously. Based on these control rules, a fuzzy control system for regulating the moromi (sake mash) temperature was constructed. A computer simulation of sake brewing indicated that the proposed control system could be applied to control the temperature along the desired curve of traditional sake brewing.