Viili源发酵菌种筛选及其复配发酵剂发酵特性分析

Screening of fermentation strains from Viili source and analysis of fermentation characteristics of compound starter cultures

中文关键词:  Viili发酵乳  复配  发酵特性

英文关键词:Viili fermented milk  compound starter cultures  fermentation properties

中文摘要:

      目的 筛选Viili发酵乳中的乳酸菌, 探讨复配发酵剂中菌种比例。方法 通过平板划线分离筛选其微生物, 根据16S rRNA序列构建系统发育树确定菌株的种属。并结合Viili发酵乳中细菌的丰度对复配比例进行设计, 对复配发酵组的酸度、胞外多糖含量、质构、挥发性风味物质进行综合分析。结果 多样性结果显示检测出4个细菌属, 其中乳球菌属(Lactococcus)、链球菌属(Streptococcus)、明串珠菌属(Leucanostoc)作为优势细菌属, 占比分别为49.12%、40.67%、10.21%。分离筛选得到乳酸乳球菌H2、嗜热链球菌H17、肠膜明串珠菌H30、副干酪乳杆菌H33。通过复配设计20组不同比例的发酵实验, 综合评估pH、凝乳时间、质构特性、胞外多糖含量及风味等指标, 结果表明, 复配组S13(活菌数之比为H2:H17:H30:H33=11:4:4:1)和S17(活菌数之比为H2:H17:H30:H33=30:35:16:19)在各项性能上与Viili发酵乳最为接近。结论 复配组S13 (H2:H17:H30:H33=11:4:4:1)和S17 (H2:H17:H30:H33=30:35:16:19 )具有作为复合发酵剂的应用价值。本研究为Viili发酵乳复配发酵剂提供了理论基础。

英文摘要:

      Objective To screen lactic acid bacteria from Viili fermented milk and explore the proportion of bacteria in the compound starter cultures. Methods Lactic acid bacteria were isolated using streak plating, and their taxonomic classification was determined through phylogenetic analysis based on 16S rRNA sequences. The composition of strain ratios in mixed cultures was designed with reference to the bacterial abundance observed in Viili fermented milk. Comprehensive analyses were performed to evaluate the acidity, exopolysaccharide production, textural properties and volatile flavor compounds of the mixed fermentation groups. Results Diversity analysis identified 4 bacterial genera, among which Lactococcus, Streptococcus and Leuconostoc were the dominant genera, comprising 49.12%, 40.67% and 10.21% of the total bacterial composition, respectively. Lactococcus lactis H2, Streptococcus thermophilus H17, Leuconostoc mesenteroides H30 and Lactobacillus paracasei H33 were isolated and screened. A total of 20 fermentation trials with different strain compositions were designed to conduct a comprehensive assessment of key parameters, including pH, coagulation time, textural properties, exopolysaccharide content and flavor profile. The results indicated that formulations S13 (H2:H17:H30:H33=11:4:4:1) and S17 (H2:H17:H30:H33=30:35:16:19) demonstrated the highest similarity to Viili fermented milk in terms of physicochemical and sensory properties. Conclusion The blended formulations S13 (H2:H17:H30:H33=11:4:4:1) and S17 (H2:H17:H30:H33=30:35:16:19) exhibit promising potential as compound starter cultures. This study provides a theoretical basis for developing compound starter cultures in Viili fermented milk production.