Koji
What the research shows
Not enough
published research on this page yet
A fungus used in Japanese cooking to ferment food.
It ferments foods and can be mixed with wheat and soybean meal.1
What research says
Animal and lab studies only
-
No harm found
No harm in animals2
In animal studies, rice koji made with Aspergillus terreus showed no clear signs of harm.
The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.
Products
The 6 most-scanned of 762 products on Open Food Facts that list koji.
- Soy Sauce Kikkoman · 296 ml 1 additive
- WHITE MISO Miso Tasty Ltd 0 additives
- Japanese Barbecue Sauce Bachan's · 34 oz (864 g) 0 additives
- Yakitori Chicken w/Japanese-style Fried Rice Ajinomoto · 1.53 kilograms, 54 ounces 4 additives
- Miso Blanc Biologique Hikari · 500 g 0 additives
- miso tasty red miso rich soybean paste Miso Tasty · 200 g 0 additives
References
- 1Kōji (food). Wikipedia. Accessed September 29, 2026. CC BY-SA 4.0.
- 2Yun JW, Kim SH, Kim YS, et al. Absence of subchronic oral toxicity and genotoxicity of rice koji with Aspergillus terreus. Regul Toxicol Pharmacol. 2017;89:244-252. doi:10.1016/j.yrtph.2017.08.004