麦芽糖化工艺的优化及其对发酵的影响

Study on Optimization of Malt Saccharification Process and Fermentation Effect

[目的]优化麦芽的糖化工艺条件,探究麦芽的水解作用规律,获得发酵优良的麦汁。[方法]以还原糖、总糖、α-氨基氮和可溶性蛋白质的含量为指标,探究麦芽蛋白质休止温度、糖化的温度、时间、初始pH等工艺参数对麦芽淀粉和蛋白质水解的影响。[结果]糖化温度是影响麦芽淀粉水解的主要因素;蛋白质休止温度、时间及初始pH是影响麦芽蛋白质水解的主要因素。麦芽糖化工艺优化结果:50℃蛋白质休止1 h,65℃糖化40 min,72℃糖化20 min,初始pH为5.0。该工艺制备的麦汁15℃发酵的酒精度达6.2%,实际发酵度达75.3%。[结论]该研究可为不同类型啤酒酿造制备特定的麦汁提供生产依据。

[Objective]To study the effects of different saccharification process on malt hydrolysis and in the meantime optimize the saccharification process and prepare good fermentation wort.[Method]Single factor experiment was conducted to evaluate the effects of malt amylolysis and proteolysis by measuring reducing sugar,total sugar,α-amino nitrogen and soluble proteins.Factors involved protein rest temperature,protein rest time,saccharification temperature,saccharification time and initial pH.[Result]The result confirmed that saccharification temperature is the critical factor of amylolysis while protein rest temperature,protein rest time,and initial pH significantly affect proteolysis of malt.The optimal saccharification process were as follow：Protein rest for 1 hour at 50 ℃,saccharify for 40 min at 65 ℃ then for 20 min at 72 ℃,initial pH 5.0.The wort produced under these conditions were fermented into alcohol,of which ethanol content reached to 6.2% and final real attenuation was 80.3%.[Conclusion]The research provides theoretical references for wort production according to different types of beers.