PRODUCTION OF ALCOHOL BY REPEATED BATCH FERMENTATION METHOD

摘要

PURPOSE:To efficiently obtain an alcohol from a raw material while reducing damage of yeast by using a glucide raw material or a starchy raw material by a repeated batch fermentation method for estimating or judging completion of fermentation through a gas flowmeter of velocity head measuring type. CONSTITUTION:A glucide raw material or a starchy raw material is supplied to a yeast tank 1, sterilized and inoculated with yeast. Yeast culture as a starter of fermentation is added to the tank, the raw material is cultured at 30-32 deg.C for 24-48 hours while continuously aerating, formed yeast culture is transported to a main fermentation tank 2 by a transporting pump 4 and mainly cultured. An exhaust gas of fermentation is measured through a scrubber 3 by a gas flowmeter of a velocity head gauging type. At a point of time when a flow rate of the exhaust gas of fermentation reaches 0.35-0.1m3 or more than the value per kl of fermentation solution per hour, the fermentation is judged completion. Stirring is stopped, the yeast culture is settled, a supernatant liquid is extracted, a new raw material solution is added and the next batch is carried out. By this repeated batch fermentation method, an alcohol is efficiently produced without damaging yeast.