酱香型白酒发酵中两株主要乳酸菌对酿造微生物群体的影响

【目的】研究从酱香型白酒发酵酒醅中分离得到的2株主要乳酸菌Lactobacillus homohiochii XJ-L1和Lactobacillus buchneri XJ-L2对酱香型白酒发酵中酿造微生物群体的作用，并探索该种相互作用对酱香型白酒品质的影响。【方法】结合抑菌实验和组合发酵实验研究L. homohiochii XJ-L1和L. buchneri XJ-L2对酿造微生物群体生长的影响，通过对纯培养和共培养体系中代谢物的比较，研究2株优势乳酸菌对主要酿造酵母风味相关代谢产物的影响。【结果】L. buchneri XJ-L2能够抑制3株芽孢杆菌(Bacillus amyloliquefaciens XJ-B1，Bacillus subtilis XJ-B2，Bacillus licheniformis XJ-B3)、5株霉菌(Aspergillus oryzae XJ-M1，Aspergillus niger XJ-M2，Aspergillus flavus XJ-M3，Aspergillus albicans XJ-M4，Rhizopus oryzae XJ-M5)、2株酵母(Schizosaccharomyces pombe XJ-Y4，Geotrichum candidum XJ-Y5)的生长；L. homohiochii XJ-L1和L. buchneri XJ-L2能够促进3株主要酵母(Saccharomyces cerevisiae XJ-Y1，Zygosaccharomyces bailii XJ-Y2，Pichia galeiformis XJ-Y3)的生长，同时促进其酸类、醇类、酯类等风味物质的代谢。【结论】L. homohiochii XJ-L1和L. buchneri XJ-L2可促进3株主要酵母的生长代谢，同时L. buchneri XJ-L2明显抑制细菌、霉菌和少数酵母的生长，以此促进和维持主要酵母在酱香型白酒发酵过程中的生态地位，从而影响酒中酸类、醇类、酯类等风味物质的形成，保证酱香型白酒的品质。因此，适当比例的乳酸菌对维持酿造微生物区系平衡，生产典型酱香品质白酒具有重要意义。

Impacts of two main lactic acid bacteria on microbial communities during Chinese Maotai-flavor liquor fermentation

[Objective] Objectives of this study were to investigate the impacts of two major lactic acid bacteria (L. homohiochii XJ-L1 and L. buchneri XJ-L2) on the microbial communities and flavor quality of Chinese Maotai-flavor liquor. [Methods] Bacteriostatic tests in vitro and mixed culture fermentation were carried out to investigate the interactions between main lactic acid bacteria and the other major microorganisms during fermentation. [Results] L. buchneri XJ-L2 could inhibit the growth of three Bacillus strains (B. amyloliquefaciens XJ-B1, B. subtilis XJ-B2, B. licheniformis XJ-B3), five mold strains (A. oryzae XJ-M1, A. niger XJ-M2, A. flavus XJ-M3, A. albicans XJ-M4, R. oryzae XJ-M5) and two yeasts (Sc. pombe XJ-Y4, G. candidum XJ-Y5). L. homohiochii XJ-L1 and L. buchneri XJ-L2 could promote the growth of three main yeasts (S. cerevisiae XJ-Y1, Z. bailii XJ-Y2, P. galeiformis XJ-Y3), and benefited for the production of acids, alcohols, esters etc. [Conclusion] The two main lactic acid bacteria, L. homohiochii XJ-L1 and L. buchneri XJ-L2, could maintain the ecological status of the main yeasts in the fermentation process through promoting the growth of three main yeasts and inhibiting bacillus, mold and few yeasts (L. buchneri XJ-L2 was more obvious). In addition, lactic acid bacteria affected the formation of acids, alcohols, esters and other flavor compounds and benefited for Maotai-flavor liquor fermentation. The appropriate proportion of lactic acid bacteria could enhance the balance of fermentation microflora. It is significant for the aroma production of Chinese Maotai-flavor liquor.