Aspergillus oryzae is a filamentous fungus, a type of mold, used heavily in Chinese, Korean, and Japanese fermented products for the distinctive flavor it imparts.  The fungus’ common name is kōji. Kōji is integral to the production of miso, soy sauce, rice vinegar, sake, fermented black beans, and other products.

Health considerations

Aspergillus oryzae has low potential to be pathogenic or allergy-inducing. It does not produce aflatoxins or carcinogenic metabolites and has never tested positive for threatening levels of mycotoxins.

May be found in

Soy sauce, tamari, fermented black bean paste, dressings, marinades, sauces, miso, miso soup, rice vinegar, pickles, sake


Applied Microbiology and Biotechnology

Alternative names and spellings


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