Aerobic conditions
Japanese: 好気的条件
An environment with sufficient oxygen. Acetic acid fermentation and koji mold growth require aerobic conditions.
Aerobic conditions mean an environment with ample oxygen. If anaerobic conditions are the stage for fermentation, aerobic conditions are the stage for koji-making and vinegar production.
Koji mold is an aerobic fungus, extending hyphae while absorbing oxygen on the surface of steamed rice and secreting enzymes. Ventilation in the koji room is critical precisely to supply oxygen to the mold.
Acetic acid fermentation is also aerobic—acetic acid bacteria convert alcohol to acetic acid while contacting oxygen at the liquid surface. In the world of fermented foods, the strategic use of anaerobic and aerobic conditions is the core technique. Removing air during miso preparation, exposing to air during koji-making—this distinction determines quality.