Off-flavor of Soy Sauce and its Prevention Method

Off-flavor is the fault of soy sauce, because flavor of soy sauce is the most important. Typical off-flavor of soy sauce is n -butyric acid which produced by Bacillus strains in Koji manufacture. The prevention of Bacillus strains is cleaning, sterilization and drying of the belt conveyor of soy sauce materials and the equipment of Koji manufacture, because of decrease of n-butyric acid. Second important off-flavor of soy sauce is isobutyric acid and isovaleric acid produced by membrane forming yeast in Moromi manufacture and final production after opening of the cap. The prevention of the membrane forming yeast is high alcohol fermentation and pasteurization before bottling.