摘要
β-葡聚糖酶主要用于啤酒工业,它能专一地分解粘度很高的各种大麦β-葡聚糖中β-1.3和β-1.4糖苷键,使麦汁粘度降低,从而缩短麦汁和啤酒的过滤时间,增加产量,并改善啤酒的质量。 试验所用菌种Bacillus Subtilis是从34株细菌中筛选并经诱变获得,它具有较高的产β-葡聚糖酶的能力。 在以淀粉、蔗糖和硫酸铵为主的培养基、pH7.2～7.5、温度为37℃条件下,进行搅拌通风培养两天。酶活力约为30U/ml。 发酵液采用絮凝剂处理,经硅藻土过滤,再将滤液经超滤或真空低温浓缩,即获得了深棕色的液体酶制剂。若进一步用酒精沉淀或进行喷雾干燥,即可制得粉末状酶制剂产品。 β-葡聚糖酶应用于啤酒糖化,对加速麦汁过滤、提高麦汁收得率,均有明显效果。
β-glucanase is a main kind of enzymes used in brewing industry. It can specially hy-drolyze mixed barley β-glucanse with high viscosity containing β-1,3 and β-1,4 glucosidic linkages and give beneficial effects on reduction of wort viscosity, decrease ia time required for filtration of the mash and the beer, increase in yield of the extract and improvement of he beer stability.A strain of Bacillus Subtilis 5014 with high activities of β-glucanase are selected out from 34 species of bacteria. The cultivation conditions are as following,starch, sugar and ammonium sulfate are taken as the main constituents of the culture medium, the inoculated culture is incubated with aeration at 37℃, pH7.2-7.5 and the finial activity of 30 BGU/ml of β-glucanase has been achieved.After the end of fermentation,the broth is subjected to flocculate with flocculant agent and followed by filtrating the supertaat with a kieselguhr filter and then the filtrate is concentrated by either ultrafiltration or vaccum evaporation at low temperature, thus the liquid enzyme preparation in dark brown is formed.The solid enzyme preparation can also be formed from the purified and concentrated enzyme solid by precipitating with et-hanol or dry in spray dryerApplication of this bacterial β-glucanase to brewing process has been trialed.The res-lults show that this enzyme preparation gives a significat effect on accelerating wort fi-tration and increasing extract yield.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
1989年第3期1-7,共7页
Food and Fermentation Industries
