发酵条件对一步法发酵菊芋生产乙醇的影响

使用产菊粉酶的酿酒酵母可实现一步法发酵菊芋生产乙醇.该试验以菊芋汁为发酵培养基,研究了起始糖浓度、无机盐、温度、种子培养基、接种量和氮源对高菊粉酶活酿酒酵母Y05-步发酵菊粉生成乙醇的影响.试验结果表明:(1)菊芋汁中最适起始总糖浓度为250g/L.菊芋汁含有的较多无机盐对乙醇发酵不但没有抑制作用,反而有促进作用；(2)最适乙醇发酵温度为37℃；(3)种子培养基中使用菊粉做为碳源有利于酿酒酵母Y05产生较多菊粉酶,进而促进其乙醇发酵；(4)最适乙醇发酵接种量为15％;(5)尽管菊芋汁是一个良好乙醇发酵培养基,但补加氮源仍是必要的.补加5.0g/L玉米浆可显著酿酒酵母Y05的提高总糖利用率、最终乙醇浓度和乙醇得率.

Influence of fermentation conditions on one-step ethanol production from Jerusalem artichoke

One-step ethanol production from Jerusalem artichoke can be carried out by using yeasts of Saccharomyces cerevisiae with inulinase activity.In this work,the influences of initial sugar and mineral salt concentration,temperature,seed culture medium and nitrogen source on ethanol fermentation of S.cerevisiae Y05 with higher inulinase activity were investigated by using Jerusalem artichoke juice as cultural media.The results showed that:(1) the optimal initial sugar concentration was 250g/L.Higher mineral salts in Jerusalem artichoke juice did not inhibit the ethanol fermentation;(2) the optimal temperature of ethanol fermentation with S.cerevisiae Y05 was 37℃;(3) iunlin as carbon source in seed culture medium was in favour of S.cerevisiae Y05 to produce more inulinase,which stimulate its ethanol fermentation;(4) its optimal inoculum size was 15%;(5) Jerusalem artichoke juice was a perfect cultural medium,but supplementation of nitrogen sources was necessary.Supplementation of 5.0g/L corn steep liquor largely enhanced initial sugar utilized,final ethanol concentration and ethanol yield of S.cerevisiae Y05.