Aerobic bacteria / Aerobic microorganisms

Aerobic bacteria are microorganisms that cannot live without oxygen. Acetic acid bacteria and koji mold are representative examples. They actively proliferate in environments exposed to air, performing efficient energy metabolism using oxygen.

The reason temperature control and ventilation are critical in koji-making is precisely because koji mold is aerobic. Without sufficient oxygen, hyphae cannot extend properly. Conversely, during miso fermentation, creating anaerobic conditions suppresses aerobic contaminants.

In fermented food production, the design of when to expose to oxygen and when to seal it off determines quality. Controlling aerobic and anaerobic conditions is one of fermentation's fundamental techniques. This insight deepens fermentation understanding further.