固定化酵母生产乙醇的研究

ALCOHOL PRODUCTION BY IMMOBILIZED YEAST

固定化酵母生产乙醇新技术的研究是国家“七五”科技攻关项目。本文论述了笔者等的主要试验结果：研制的固定化增殖酵母Ｃ─Ａ─Ⅲ耐糖渗和耐酒精等性能均优于游离酵母，可于发酵液中悬浮，在连续发酵中表现出良好的传质状态和稳定的性状；酒精连续发酵采用玉米淀粉糖液为原料；筛选的耐高渗酵母菌株Ｓ．ｃｅｒｅｖｉｓｉａｅＹ─０８发酵快，后劲足；三级串联悬浮床反应装置结构简单；通过添加抗菌素和调节糖液的ｐＨ值防治杂菌侵染；通过输入少量无菌空气和微量（ＮＨ＿４）ＳＯ＿４维持固定化酵母的活性；中型试验连续发酵１０８天，耗用原料７３４０公斤，成熟发酵醪平均酒精浓度１０．３％（ｖｏｌ），糖利用率９１．６８％，载体产率３１．８８克乙醇／升载体／小时，反应器产率４．７８克乙醇／升／小时，达到国内领先水平。

The alcohol prodnctiin by immobilized yeast is studied. The resi- stance of imobilized yeast C-A- for sngar and alcohol is higher than that of free cell.It can snspend in fertoentable solntion displaying good intermass diffusion and stable character in continuous ferment.The raw material adopts the saccharic solu- tion of corn starch.Teh S. cerevisiae Y-08 yeast ferments faster and lasts longer activity duration.The reactive apparatns of three-step-Beries suspensible bed is simple.Using antibiotics and regulating the PH of saccharic solntion,this procedure is free from the pollution of bacterium. Offering asmall amount of sterile air and trace ammonium snlfate,we could maitain the acivity of immobilized yeast.Consuming 7340 kg raw materials,the successive ferment lasts 108 days in the procednre of me- dium sized test.Average alcohol concentration of martnre fermented liqnor is 10.3% v/v),and saccharic ntilization ratioo is 91.7%.The alcohol productivity of carrier and reactor ia 31. 9 g/lc.h and 4.8 g/lr.h respectively.nese indices are snrperior than all other domestic records.