Koji Starter

Aspergillus oryzae ( Japanese: 麹, kōji, or 麹菌) is a filamentous fungus (a mold). It is used in Chinese and Japanese cuisine to ferment soybeans to produce soy sauce and miso. It is also used to sweeten rice, other grains, and potatoes in the making of alcoholic beverages such as sake, and shōchū. The fungus is also used for the production of rice vinegars. The importance of A. oryzae has led to its recognition as Japan's national micro-organism ("kokkin"), just as the sakura cherry blossom is Japan's national flower.

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