Seimai ketsugen (rice polishing weight loss)

Seimai ketsugen (精米欠減) refers to the loss of weight that occurs during rice polishing. When brown rice is milled into white rice, parts such as broken rice, the outer layers, and bran are removed, so the weight of the white rice after polishing is normally lower than the weight of the original brown rice. This difference in weight is recognized as seimai ketsugen, and in sake brewing it also serves as an important indicator when evaluating how far the rice has been polished. Because seimai ketsugen can affect the quality, aroma, and flavor of the sake, careful management of the polishing process is considered important.