酿酒酵母发酵高浓度乳清粉生产燃料乙醇

摘要

利用酿酒酵母NL22对乳清粉进行分步糖化发酵(SHF)和同步糖化发酵(SSF),对其生产燃料乙醇的条件进行比较,同时考察pH、温度和底物浓度对SHF和SSF过程的影响.结果表明:SHF工艺和SSF工艺都可以实现酿酒酵母NL22对高浓度乳清粉的发酵,但SSF工艺可明显缩短生产周期,提高生产效率.在pH 6和30℃的条件下进行补料同步糖化发酵,最终乙醇质量浓度为118.52 g/L,产率为1.74 g/(L·h).%We studied two different processes,namely separate hydrolysis and fermentation ( SHF) and simultaneous saccharification and fermentation( SSF) ,to produce ethanol from high concentration of whey powder by Saccharomyces cerevisiae NL22.Effects of pH,temperature,and substrate concentration on both process were studied.Both SHF and SSF process produced ethanol efficiently from high concentration of whey powder,but the productivity of SSF was much higher. Under the condition of pH 6 and 30 ℃, 118. 52 g/L bio-ethanol was produced by fed-batch SSF with the productivity of 1. 74 g/( L·h) .