小麦B淀粉一步酶解产糖优化及酒精发酵

Optimization of One-step Enzymatic Sugar Production from Wheat B Starch and Ethanol Fermentation

以小麦B淀粉为原料,优化其一步酶解制备可发酵糖的工艺及后续酿酒酵母发酵生产酒精,提高其利用价值。首先对小麦B淀粉基本组分含量进行测定,其次使用α-淀粉酶和糖化酶组成复合酶对小麦B淀粉进行一步酶解制备可发酵糖,详细考察复合酶用量、料液比、酶解温度、酶解时间及pH对还原糖得率影响,对以上参数进行正交优化,获得酶解最佳工艺条件,最后利用酿酒酵母发酵所得酶解糖液生产酒精。结果表明,小麦B淀粉中淀粉含量85.61%,蛋白质和灰分含量都达到2%左右,戊聚糖含量接近5%,通过正交优化确定酶解产糖最佳条件为复合酶用量4 mL,料液比1:25 g/mL,酶解温度60℃,酶解时间10 h,pH5.0,在此条件下还原糖得率达到94.6%。利用酵母发酵产酒精,最终酒精浓度达到12.76 g/L,酒精原料得率为31.90%。本研究为小麦B淀粉制备酒精工艺提供参考。

Using wheat B starch as raw material,optimize the one-step enzymatic hydrolysis process for preparing fermentable sugars and subsequent fermentation of alcohol by brewing yeast to improve its utilization value.Initially,the elemental composition of Wheat B starch was quantified.A composite enzymatic catalyst containingα-amylase and saccharase were then employed to generate fermentable sugars from wheat B starch through enzymatic hydrolysis efficiently.Various parameters,including composite enzyme concentration,solid-liquid ratio,enzyme temperature,enzymatic duration,and pH were thoroughly investigated to assess their effects on reducing sugar yield.An orthogonal optimization approach was conducted to determine the optimal conditions for enzymatic hydrolysis.Results showed that wheat B starch contained 85.61%starch,with approximately 2%protein and mineral content,and pentosan composition nearing 5%.Following the orthogonal optimization,the most effective parameters for enzymatic saccharification were identified:A composite enzyme dosage of 4 mL,a solid-liquid ratio of 1:25 g/mL,an enzymatic digestion temperature of 60℃,an enzymatic digestion duration of 10 h,and a pH of 5.0.Under these specific conditions,the yield of reducing sugar reached 94.6%.Subsequently,wheat B starch was converted into alcohol through yeast-mediated fermentation.This process led to a final alcohol concentration 12.76 g/L,accompanied by an alcohol yield of 31.90%.In conclusion,wheat B starch holded remarkable promise for large-scale bioethanol production,providing valuable insights for maximizing the utilization of this resource on a broad scale.