What shubo means
Shubo is the starter in sake brewing in which yeast is cultivated in quantity to ferment the main mash; it is also called moto. A JETRO Oita explanation of sake making describes the stage as cultivating strong yeast in a starter tank to ferment the mash. Koji made in the Kojimuro is combined with steamed rice and water, and the yeast is grown in this mixture.
Once the starter is ready, koji, steamed rice and water are added to it in several stages to build up the main mash. Temperature control matters greatly, and breweries often have a dedicated room or building for making the starter.
Reading the records
Cultural property records mention the facilities by names such as shubo storehouse or shubo room. The shubo storehouse of the Hirata Dairoku family in Sekikawa, Niigata, a long narrow building six and a half bays by two, is recorded as having been used to prepare and raise yeast starter when the family ran a brewery; its rough clay walls are protected by an outer enclosure of vertical boarding.
Brewery buildings are often divided by stage into koji rooms, starter rooms, brewing houses and storage buildings. Articles should use the record's name and description to determine which stage a building served.
References
- 清酒の製造工程｜ジェトロ大分
- https://www.jetro.go.jp/jetro/japan/oita/industry/brewery/seisyu.html
- 平田大六家住宅酒母蔵｜国指定文化財等データベース（文化庁）
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00001330
Last verified: 2026.09.26