koji

Koji is a starter culture used in Japanese cuisine, primarily made from rice inoculated with Aspergillus oryzae mold. This mold develops a mycelium on the rice, creating a starter that is essential for fermenting various products.1

Koji is a key ingredient in making miso, a fermented paste of soybeans, grain (like rice or barley), and salt. The koji acts as a starter culture for miso, soy sauce, and sake. Different types of rice used with koji result in variations like white miso (from white rice) and red miso (from red rice). Miso, with its rich, umami flavor, is a versatile ingredient used in soups, sauces, dressings, and pickling.2