天津地区酱香白酒生产中产吡嗪芽孢杆菌的应用

Application of pyrazine-producing Bacillus in the production of Maotai-flavor Baijiu in Tianjin

摘要:

【背景】 吡嗪类化合物与酱香型白酒的酱香风味关系密切。【目的】 筛选出高产吡嗪类化合物芽孢杆菌(Bacillus sp.)应用于白酒生产中，为提升酱香型白酒品质提供依据。【方法】 从50株来源于酱香型白酒酿造过程的芽孢杆菌中经初筛、复筛筛选出一株高产吡嗪类化合物的芽孢杆菌J1，对其进行16S rRNA基因分子生物学鉴定，通过单因素和正交试验对菌株产吡嗪条件进行优化，通过模拟发酵和原位发酵验证其发酵效果。【结果】 菌株J1为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)，接种菌液浓度为10⁷ CFU/mL，酿酒酵母(Saccharomyces cerevisiae)与J1接种比例为1:100，菌株J1接种时间为接种酿酒酵母后2 d，升温至50 ℃为最优发酵条件，其吡嗪含量可达322.48 mg/L。模拟发酵表明该菌株所产吡嗪种类丰富。原位发酵所得白酒中吡嗪类化合物含量为480.87 mg/L，约是对照组的10倍。【结论】 本研究可为提升酱香型白酒品质提供依据。

关键词:酱香型白酒;吡嗪类化合物;芽孢杆菌;原位发酵

Abstract:

[Background] Pyrazines are closely related to the flavor of Maotai-flavor Baijiu. [Objective] To screen out the Bacillus strains with high yields of pyrazines for Baijiu production and provide a basis for improving the quality of Maotai-flavor Baijiu. [Methods] After primary screening and secondary screening, strain J1 with a high yield of pyrazines was screened out from 50 strains of Bacillus in the brewing process of Maotai-flavor Baijiu. The strain was identified by 16S rRNA gene sequencing. The conditions of pyrazine production by this strain were optimized by single factor and orthogonal experiments. Finally, the fermentation performance of the strain was evaluated by simulated fermentation and in-situ fermentation. [Results] Strain J1 was identified as Bacillus amyloliquefaciens. The optimum fermentation conditions were as follows: inoculum concentration of 10⁷ CFU/mL, Saccharomyces cerevisiae to J1 ratio of 1:100, inoculation of J1 two days after inoculation of S.cerevisiae, and the fermentation temperature raised to 50 ℃. Under these conditions, the content of pyrazines reached 322.48 mg/L. The simulation experiment showed that the strain J1 produced rich pyrazines. The content of pyrazines in the Baijiu obtained by in-situ fermentation was 480.87 mg/L, which was about 10 times that of the control group. [Conclusion] This study can provide a basis for improving the quality of Maotai-flavor Baijiu.

Key words:Maotai-flavor Baijiu;pyrazines;Bacillus sp.;in-situ fermentation