Moyashika (bean sprout aroma)

Moyashika refers to a green, grassy aroma that arises during koji making, particularly during the nakashigoto stage (the middle stage of the process). It gets its name because the scent evokes the freshness of bean sprouts (moyashi). It is often caused by the action of enzymes produced by koji mold, and it changes into a variety of other aromas as fermentation progresses. The aroma is sometimes also called "ohaguro odor" (オハグロ臭), and in sake brewing its components can affect the flavor and aroma of the sake. When properly managed, moyashika can contribute to improving sake quality.