With the increase of temperature, the biological activity of fermenting microorganisms decreases, which leads to death and glycolysis process cannot be carried out.

When making rice wine, it should be noted that:

1) distiller's yeast must be thoroughly cooled before mixing. Otherwise, if the temperature is too high, glutinous rice will kill botrytis cinerea. The result is either sour or smelly, or nothing happens.

2) Be sure to seal it. Otherwise it will be sour and astringent.

3) Low temperature. About thirty degrees Celsius is the best. The improvement method is to lower the temperature and add koji again. Because the bacteria in the previous koji have died because of the high temperature.