Study Of Microflora During The Production Of Taibai Liquor

Progresses on the fermented grains, pit mud and distiller's yeast were reviewed in the dissertation and in order to know the diversity, the constitution, and the dynamic change of microflora in the environment, the fermented grains, pit mud and distiller's yeast of the four seasons in the year were studied.The results of morphological and biochemical physiological identification showed the main microbes in the making of Taibai liquor were bacteria, mould, yeast and actinomyces. Lactobacillus, Acetobacter and Bacillus were main groups in bacteria. Rhizopus, Mucor, Aspergillus and Penicillium were main classes in moulds. Streptomyces was dominate group of actinomyces, there were also a small number of Micromonosporaceae and nocardia. Saccharomyces cerevisiae, Candida and Hansenula were main groups in yeast.The dynamic changes of microflora in fermented grains in four seasons were showed as follow:In spring, the yeast, mould and aerobic bacteria were main floras after 5d fermentation. Yeasts were the most proliferated microbe, mould and aerobic bacteria after, the actinomyces proliferated least; the yeast, mould and aerobic bacteria were remain the main microbes after 8d fermentation, but the number of yeasts and aerobic bacteria decreased, mould increased on the other hand. Though actinomyces was not the main flora, its amount reached the highest after 8d fermentation; the number of yeasts increased sharply and reached its highest level in spring after 18d fermentation, spore bacteria became another dominant flora at the same time. Mould and actinomyces decreased drastically to the bottom of the quantity.In summer, aerobic bacteria were the main flora after 3d fermentation; yeasts, mould and aerobic bacteria become dominant in the pit after 5d fermentation. Mould and aerobic bacteria proliferated to their highest level, aerobic bacteria decreased on the contrary; aerobic bacteria and spore bacteria were the most while the quantity of mould and actinomyces decreased drastically in fermented grain after 12d fermentation.In autumn, microflora in fermented grains dominated by yeasts, mould, the amount of actinomyces proliferated sharply after 4d fermentation; aerobic bacteria and spore bacteria increased drastically while yeasts, mould and actinomyces decreased on the other hand after 7d fermentation; 18d later from the beginning of the fermentation, the number of yeasts, aerobic bacteria and mould decreased to some extent, but spore bacteria increased comparatively.In winter, the main floras in fermented grains were yeasts, aerobic bacteria, spore bacteria and mould after 4d fermentation; after 8d fermentation, the quantity of aerobic bacteria, aerobic bacteria, increased and become main floras; spore bacteria still increased after 15d fermentation and dominated.The dynamic changes of microflora in pit mud were almost the same in for seasons. The main flora in pit mud was bacteria of different classes, among which the spore bacteria was the most. Aerobic bacteria and spore bacteria first decreased then increased with the depth of the pit increased; the amount of mould and yeasts decreased by and by while actinomyces indicated no significant dynamic changes and its quantity always the smallest in different depths.The dynamic changes of microflora in distiller's yeast of different stages in four seasons showed the same result. Aerobic bacteria, mould and yeast were main floras at the beginning, all microbes proliferated to the highest amount in one period of the middle stages (including Chaohuo, Dahuo and Houhuo period), mould, yeasts and spore bacteria at the end. Actactinomyces wasn't main group in the processes of forming distiller's yeast, its amount was larger in the middle.