High Gravity Alcoholic Fermentation from Sugarcane Molasses by a High-yield Saccharomyces cerevisiae Strain MF1001 in Industrial Scale

A high-yield Saccharomyces cerevisiae strain MF1001 was used for high gravity alcohol fermentation of sugarcane molasses in industrial scale.The fermentation system was composed of 9 fermentors(No.1~No.9),of which the No.1 was used for cultivating the strain with low gravity of molasses medium,the No.2 was used for initiating the fermentation by mixing the low-and high-gravity molasses medium,and the No.3~No.9 fermentors were used for continuing the fermentation.The fermentation temperature,controlled by water cycle pipe system equipped within No.1~4 fermentors,was 30~32℃(No.1),34~36℃(No.2 and No.3),30~32℃(No.4),33~35℃(No.5 and No.6),34~36℃(No.7~No.9).The medium flow was controlled to 64m3/h by quantity pumps.The pH value was adjusted at 3.6~3.8 for low gravity medium and at 3.8~4.0 for high gravity medium respectively.The graity was controlled about 20°Bx for low graity medium and 40~47°Bx for high graity medium.The results from 15-day continuing production showed that,after 49.5h fermentation,the maximum average alcoholic concentration in broth was 14.1%(V/V) for shift production and 13.8%(V/V) for day production,respectively.Based on fermentable sugar content in medium,the fermentation efficiency of whole production period was calculated,and the average was 97.72% with the maximum reached to 98.89% of theoretic value.The waster water effluent for production of 1 ton alcohol(95%,m/V) was decreased to 7.57 tons at lowest and 8.17 tons at average.The fermentation level reflected from production parameters was significant better than that of current production in China.