甘薯渣同步糖化发酵生产酒精的工艺优化

Process optimization on alcohol production using sweet potato residue by simultaneous saccharification and fermentation method

为了综合利用甘薯淀粉工业废渣,本研究以甘薯渣为原料发酵生产酒精,并对其同步糖化发酵工艺(SSF)进行优化。研究同步糖化发酵时影响酒精发酵工艺的9个因素,采用Plackett-Burman试验设计筛选出显著因素,并在筛选结果的基础上,用最陡爬坡途径逼近最大响应区域,然后利用响应面分析法确定其最佳参数。结果表明,影响酒精发酵工艺的显著因素为糖化酶、接种量和发酵温度。酒精发酵优化最佳参数为:α-淀粉酶8U/g,液化时间1.5h,液化温度90℃,硫酸铵质量分数0.15g/100g,pH值4,发酵时间36h,糖化酶151U/g,接种量0.3%,发酵温度36℃。在此条件下,验证试验得到的酒精体积分数达到17.15%,接近理论预测值16.95%。优化后的工艺可为甘薯渣同步糖化发酵生产酒精提供技术参考。

To comprehensive utilize sweet potato starch industrial waste residue,simultaneous saccharification and fermentation（SSF） method was optimized to produce alcohol using sweet potato residue.Plackett-Burman design was used to select significant factors among 9 factors which had influenced on alcohol fermentation.Based on the selected results,steepest ascent method was used to approach the optimal region and response surface methodology was adopted to identify optimal values of significant factors.The results indicated that the effects of glucoamylase,inoculation ratio and fermentation temperature on alcohol fermentation was significant（P〈0.05）.The optimal conditions for alcohol fermentation were as follows：α-amylase 8 U/g,liquefying time 1.5 h,liquefying temperature 90℃,mass fraction of ammonium sulfate 0.15 g/100 g,pH value 4,fermentation time 36 h,glucoamylase 151 U/g,inoculation ratio 0.3% and fermentation temperature 36 ℃.Under the optimum conditions,alcohol concentration was 17.15%,which was close to theoretical predicted value（16.95%）.The optimum technology provides reference for the alcohol production technology by SSF method for sweet potato residue.