How is it made in the first place?
The general sequence of events is as follows.
1. Soak the rice in water the day before to absorb the water.
2. Steam the soaked rice in a steaming kettle.
3. Cool the steamed rice until it reaches the right temperature.
4. Bring the rice to the room and soak it in the fungus.
5. Every few hours, "care" by mixing with bare hands to deliver oxygen, and put it to bed while controlling the temperature.
These processes take place over a period of about three and a half days. Soil bacteria have been living in the "muro", which is said to be the lifeline of manure making, for hundreds of years, and these bacteria are mixed with the resident bacteria of the craftsman's hands and fecal bacteria to make good manure. The origin of the kanji "糀" is that the mycelium that covers the rice looks like a flower. The rice bran made by the company sticks to the traditional manufacturing method and is done by hand without mechanization as much as possible.
"If you damage the rice, it will dry out and the mycelium will not grow, so the right amount of force is important. Fermentation is not so much about controlling it efficiently, but about the person who makes it. The temperature in the room should be 35-40 ° C, both in summer and in winter. It's quite a grueling process, but if you don't do it well, the next processed product won't taste good, so the work here is very important."