利用甘薯发酵生产燃料乙醇的工艺参数优化

Optimization of fermentation parameters for the production of fuel ethanol with sweet potato

以甘薯块茎为原料在实验室条件下发酵生产燃料乙醇,采用低温液化及同步糖化发酵相结合的工艺,应用耐高温活性干酵母,研究了影响甘薯生产燃料乙醇的主要因素,并确定了最佳发酵条件,最佳发酵条件:100g薯浆中的加水量为70ml,液化酶的添加量为30μl,86℃保温条件下液化时间为90min,糖化酶的添加量为100μl,醪液发酵前不用进行pH调节,也无需添加无机盐、氮源等营养物质,30℃恒温条件下同步糖化发酵的时间为60h。试验结果表明,甘薯样品"商薯19"在此发酵条件下的乙醇产量达到12.66g/(100g)鲜薯,转化效率为92.0%。

The production of fuel ethanol with fresh sweet potato roots was investigated in laboratory,using the technology of low-temperature liquefaction and simultaneous saceharification and fermentation （SSF） ,combined with the high-temperature re- sistant active dry yeast. The main factors affecting ethanol fermentation of sweet potato were analyzed and discussed, and the fermentation parameters were optimized as ： 70 ml water,30/,1 a-amylase per 100 g sweet potato pulp,and liquefaction at 86 ℃ for 90 min;No requirement for pH adjustment and addition of mineral and nitrogenous nutrients; 100μl amyloglucosidase per 100 g sweet potato pulp for saccharification;SSF was performed at 30℃ for 60 h with continuous shaking. Under the optimum conditions, ethanol yield and conversion efficiency of a sweet potato cultivar, Shangshu 19, were 12.66 g ethanol per 100 g fresh pulp and 92.0% ,respectively.