Motooroshi (transferring the yeast starter into the brewing tank)

Motooroshi is the step in sake brewing in which the shubo (yeast starter, also called moto) is transferred into the brewing tank for the first addition (hatsuzoe) of the main mash. The shubo plays a key role in starting fermentation, and this step carries its activity over into the new mash, laying the foundation for brewing better sake. When done properly, it has a significant effect on the flavor and quality of the sake.