基于缺失重组实验的藏灵菇优势菌种对发酵乳品质的影响

Effect of dominant strains of Tibetan kefir on fermented milk quality based on deficiency recombination experiments

为筛选藏灵菇发酵剂并探究其优势菌种对发酵乳品质的贡献,分别比较了8份自然藏灵菇和冻干藏灵菇发酵乳的品质差异,依据菌株活性和品质相似性筛选出一份适用于制备冻干发酵剂的藏灵菇,并分析其优势菌种,通过菌种缺失重组试验,探究各优势菌种对发酵乳品质的影响。结果表明冻干藏灵菇发酵剂的优势菌种包括Kazachstania unispora(单孢哈萨克斯坦酵母)、Lactobacillus kefiri(开菲尔乳杆菌)、Lactococcus lactis subsp. lactis strain(乳酸乳球菌乳酸亚种)、Leuconostoc mesenteroides(肠膜明串珠菌)、Acetobacter cibinongensis(芝庇侬醋杆菌)和Acetobacter fabarum(可可豆醋杆菌),这些优势菌种对细菌总数、酸度、持水力和关键香气成分等指标会产生显著差异。本研究探究了藏灵菇优势菌种对发酵乳品质的影响,为开发冻干藏灵菇发酵剂和藏灵菇发酵乳工业化生产提供了参考。

In order to screen the Tibetan kefir ferment and investigate the contribution of its dominant strain to the quality of fermented milk,we compared the quality differences between eight natural Tibetan kefir and freeze-drying Tibetan kefir fermented milk,and selected a suitable Tibetan kefir for the preparation of freeze-drying fermenters based on strain activity and quality similarity,and analyzed its dominant strain.Then the effect of each dominant strain on the quality of fermented milk was investigated through strain compounding and deletion-deletion recombination tests.The results showed that the dominant strains of freeze-dring Tibetan kefir fermenters included Kazachstania unispora,Lactobacillus kefiri,Lactococcus lactis subsp.lactis strain,Leuconostoc mesenteroides,Acetobacter cibinongensis and Acetobacter fabarum.These dominant strains can produce significant differences in indicators such as total bacterial count,acidity,water retention and key aroma components.This study investigated the effect of the dominant strain of Tibetan kefir on the quality of fermented milk,and provided a reference for the development of freeze-drying Tibetan kefir ferment and the industrial production of Tibetan kefir fermented milk.