La brasserie San-Ô
by Koji Soupe& Labo

Koji is not eaten on its own, but when the food is cooked/marinated with Koji, the enzyme in the fermented rice helps to bring out the flavor of food and improve the tenderness of the meat. ​

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Enzymes in Koji decompose protein into amino acids, a source of savory (which is called "Umami"). By the action of these enzymes, the meat is tenderized with better taste.