Moto, the Sake Starter: Steamed Rice, Koji and Water Fermented Cold for Fourteen Days (Itami, after Rein 1889)

Old sake brewers added no bought yeast. They made a small, cold mash first, the moto, and let it ferment for two weeks: the koji turns starch to sugar, and the yeast that settles in it grows strong in the cold. The finished moto, sour, bitter and alcoholic, seeds the main brew. Result: moto, 3 to 14 % alcohol (Nishinomiya 10.5 %). Source: J. J. Rein, The Industries of Japan (1889), pp. 98-99, the brewers of Itami. Picture drawn by Youblob.