Shikomi-mizu
仕込み水
Definition
The brewing water used in sake production — added to the moromi during fermentation and used for dilution after pressing. Shikomi-mizu quality is critical because it constitutes roughly 80% of the finished product.
In Depth
Each brewery selects its shikomi-mizu carefully, typically from wells, springs, or municipal sources that meet strict quality requirements. The water must be low in iron (below 0.02 mg/L) and manganese to prevent discoloration and off-flavors. Beyond these minimums, the mineral profile of shikomi-mizu shapes the brewery's house style. Breweries often consider their water source their most important asset, and some go to extraordinary lengths to protect it — purchasing surrounding land to prevent contamination or drilling deep wells to access pristine aquifers.