Places used for sake mash-making are called shuboshitsu (literally, chamber of sake mash) or motoba (literally, place of sake mash) and the room temperature is kept around five degrees Celsius so that no undesirable bacteria or natural yeast will enter.
酒母造りの場所は、酒母室（しゅぼしつ）もしくは酛場（もとば）と呼ばれ、雑菌や野生酵母が入り込まないように室温は5℃ぐらいに保たれている。