Comparison of ethanol production from different sugar feedstocks by solid state fermentation with two yeast strains

In order to find out suitable raw materials and strains for ethanol production by solid state fermentation, three kinds of sugar crops and two yeast strains were tested to compare their characteristics of ethanol/sugar conversion. One of the two strains investigated is TSH-CGMCC1949 strain, screened from sweet sorghum plant, and the other one is Angel yeast, generally used in current alcohol industry. The three kinds of sugar crops investigated were sugar cane, sugar beet and sweet sorghum stalks. The results showed that, with the same feedstock input quantity, the ethanol production from sugar beet was the highest, following by sweet sorghum, because of different initial sugar content. In order to eliminate the effect caused by varied sugar content, ethanol yield (g ethanol/g sugar consuming) was employed to compare the fermentation efficiency. Sweet sorghum stalks had attained the highest ethanol yield of the three materials. TSH performed some advantages through the contrast to AGL. TSH had shorted the fermentation period by nearly 6 h, and the ethanol yield was higher than that with AGL. The results indicated that, TSH had a wide substrate rage, applicable to many sugar crops in addition to sweet sorghum.