Koji Spores

Koji spores are the reproductive cells of a fungus, typically *Aspergillus oryzae*. This fungus is cultivated on grains like rice or soybeans, where it grows and produces enzymes. These enzymes are key to breaking down starches and proteins, which is essential for fermenting foods.

Koji spores are used as a starter culture in fermentation, primarily to produce enzymes that break down starches and proteins. This process develops unique flavors and textures in foods like soy sauce, miso, sake, and some vinegars. Manufacturers use it to enhance savory (umami) flavors and tenderize meats.

Koji is generally recognized as safe (GRAS) by the FDA for use in food. The enzymes produced by *Aspergillus oryzae* are involved in breaking down complex molecules into simpler ones, which can aid digestion. International bodies like JECFA have evaluated *Aspergillus oryzae* and its enzymes, but no specific numeric limits are typically set for its use as a fermentation culture. Evidence does not suggest adverse health effects from consuming foods fermented with koji at typical levels.