二种重组α-乙酰乳酸脱羧酶在啤酒生产中降低双乙酰的作用

APPLICATION OF THE RECOMBINANT α-ALDCs FOR REDUCING THE CONCENTRATION OF DIACETYL DURING BREWING PERFORMANCE

利用已构建的含有短芽孢杆菌（Ｂａｃｉｌｌｕｓ ｂｒｅｖｉｓ）和产气肠杆菌（Ｅｎｔｅｒｏｂａｃｔｅｒ ａｅｒｏｇｅｎｅｓ）α－乙酰乳酸脱羧酶（α－ａｃｅｔｏｌａｃｔａｔｅ ｄｅｃａｒｂｏｘｙｌａｓｅ， α-ＡＬＤＣ）基因的工程菌株，并使它们分别在大肠杆菌中高效表达，获得重组α－ＡＬＤＣ。在实验室，用 ２Ｌ体积的麦芽汁进行啤酒生产试验，添加 ２种重组α－ＡＬＤＣ后，使啤酒中的双乙酰含量快速下降到或始终保持在０.１ｍｇ／Ｌ以下。证明得到的重组ａ－ＡＬＤＣ能有效地降低啤酒中双乙酰含量。

Two a-ALDC genes were cloned from Bacillus brevis and Enterobacter aerogenes by PCR amplification. Both genes over expressed α-ALDC in E Coli DH5α. In laboratoryscale(2L) brewing with the recombinant αALDCs the formation of diacetyl in beer was much lower than control. The result indicated that the recombinant αALDCs caused a decrease in diacetyl production during beer fermentation.