Fermentation room
The starter mash, water, koji, and steamed rice go into stainless steel fermentation tanks, and take two to three weeks to ferment into the main mash. The temperature of the room is maintained at 10-12˚C (50-53.6˚F), and the tanks are kept cool by cold water circulating through plate coils affixed to their outer walls.
(Fifty-six 20,000-liter tanks can prepare 19,600 kg of main mash per day.)