Talk about sake
Effect of ShikomimizuShikomimizu is water for brewing sake. It is used in most every process, starting from rice washing, soaking, up to water addition to lower the alcohol concentration of unprocessed sake. Some breweries are committed to using shikomimizu to wash tools and equipment.
According to the World Health Organization’s standards, water containing calcium carbonate at concentrations below 60 mg/l is generally considered as soft; 60–120 mg/l, moderately hard; 120–180 mg/l, hard; and more than 180 mg/l, very hard. For shikomimizu, moderately hard water and soft water are mainly used. Moderately hard water, which is abundant of minerals and easy to ferment, creates crisp and dry sake. Soft water with less minerals creates mellow and mild sake. There are so many exquisite and well-conserved waters (meisui) in Japan, but some of them are not suitable for shikomimizu, though they taste very good. For instance, water containing plenty of iron and manganese tends to cause discoloration and deterioration of sake.
Rice and koji are necessary for sake brewing and they can be brought from remote places, while a large amount of shikomimizu is required for sake brewing and breweries have no choice but to use local spring water. However, even if they cannot collect plenty of water within their premises, the water is not far so that they can collect it every day. You could say shikomimizu plays a leading part to create local unique taste.