Tokomomi (rubbing koji spores into steamed rice by hand)

Tokomomi is the step in which steamed rice is spread out on the floor (toko) of the koji room (koji muro), seed koji (tane koji, koji mold spores) is sprinkled evenly over it, and the rice is then rubbed by hand so that the koji spores adhere firmly to the grains. This process is important so that the koji mold spreads evenly across the rice and fermentation can proceed efficiently. Tokomomi is also commonly called "tokogaeshi," and it is an essential step in sake production as an important stage of the brewing process.