摘要
米根霉具有较强的产淀粉糖化酶能力。本研究通过对米根霉液态发酵工艺条件的研究来提高其产糖化酶能力,为红曲黄酒纯种酿造技术奠定基础。以米根霉为出发菌株,大米液化液作为碳源进行摇瓶发酵,通过正交试验优化液态培养基配方,并通过单因素试验得出米根霉的培养条件。优化的摇瓶发酵最佳培养基为:液化液浓度50%,NH4Cl 5 g/L,KH2PO41 g/L,MgSO4·5H2O 0.3 g/L,FeSO4·7H2O 0.4 g/L,CaCO38 g/L;发酵条件为:初始pH6.0,装液量50 mL,摇床转速150r/min,接种量6%,发酵温度为32℃。该发酵条件下,菌株摇瓶发酵液的糖化酶活力达到196.6 U/mL±8.1 U/mL。
Rhizopus oryzae exhibits strong capability of producing amyloglucase. In this study, the technical conditions of liquid fermentation of Rhizopus oryzae had been optimized to improve its glucoamylase-producing capability and to lay foundations for pure species fermentation of red starter yellow rice wine. In the experiment, Rhizopus oryzae was used as the starting strain and then inoculated in liquefied rice which used as the carbon source for shake-flask fermentation. The optimized culture mediums through orthogonal test for liquid fermentation were composed of liq-uefied rice starch 50%（v/v）, 5.0 g/L NH4Cl, 1.0 g/L KH2PO4, 0.3 g/L MgSO4·5H2O, 0.4/L FeSO4·7H2O and 8.0 g/L CaCO3. And the optimized fermenting conditions through single factor test were summed up as follows：initial pH6.0, liquid volume in flask was 50 mL, rotation speed was 150 r/min, the inoculating quantity was 6% （v/v）, and fermenting temperature was at 32℃. Under the above conditions, the activity of the pro-duced glucoamylase could reach up to 196.6 U/mL±8.1 U/mL.
出处
《酿酒科技》
北大核心
2014年第9期9-13,共5页
Liquor-Making Science & Technology
基金
国家自然科学基金资助项目(31371820)
关键词
米根霉
液态发酵
糖化酶
发酵条件
黄酒
Rhizopus oryzae liquid fermentation glucoamylase fermentation conditions yellow rice wine
