Kanshitsusa (dry-wet bulb difference)

Kanshitsusa (dry-wet bulb difference) refers to the difference between the temperatures shown by a dry-bulb thermometer and a wet-bulb thermometer, and it is used mainly to manage temperature and humidity. The dry-bulb thermometer shows the ordinary air temperature, while the wet-bulb thermometer shows the temperature when its bulb is kept moist. By using this difference, the humidity in a koji room (koji muro) or other brewing areas can be managed effectively. The relative humidity obtained from the dry-wet bulb difference makes the relationship between temperature and humidity easier to understand, and it serves as an important indicator for maintaining an environment suited to brewing. This helps establish the conditions needed to produce good-quality sake.