Magnesium

Magnesium is one of the important minerals found in the brewing water (shikomi-mizu) used to make sake. It is an essential component for the growth of koji mold and yeast, and it helps fermentation proceed smoothly. Magnesium also influences the taste of sake, playing a role in bringing out umami and body (koku). Together with the components of the sake rice, the appropriate magnesium content has a significant bearing on the sake quality that a brewery aims for, so managing the composition of the brewing water is extremely important.