- Old kōji; young kōji
When making hine-koji , care is taken that the culture room (sei-kiku – shitsu) doesn’t get too dry, and the time taken per batch of koji is lengthened. The timing of the various processes is on the slow side, the temperature of the batch is kept high, and the growth of the koji -kin is taken as far as possible. Hine-koji is so-haze style, with high concentrations of the products of koji growth, and matured to high levels of enzyme activity.
The opposite applies to waka-koji . The timing of the processes is brought forward, temperature is kept low, and so the growth of the koji is slowed. Waka-koji is aromatic tsuki-haze style. In Nada hine-koji is conventionally used for shubo, and waka-koji for moromi.