摘要
乳酸菌的自溶特性可对发酵乳制品品质产生影响，发酵剂菌体快速自溶不仅缩短酸乳发酵周期、降低了生产成本，同时菌体自溶之后释放的胞内物质又决定着酸乳的风味和感官特性。为了复配出一种高质量的复合型酸乳发酵剂，该文对前期研究筛选出的3株高度自溶的酸乳发酵剂菌株：德氏乳杆菌保加利亚亚种（Lactobacillus delbrueckii ssp. Bulgaricus）LD3-A3、唾液链球菌嗜热亚种（Streptococcus salivarius ssp.）GS1-A8和乳酸乳杆菌（Lactobacillus lactis）S15-A3进行复配，运用二次正交旋转组合设计复合发酵剂中各菌株比例，并讨论了3株菌株之间的共生关系和交互作用，根据所建模型优选结果，最后确定3种菌株最优组合方案为：GS1∶LD3-A3∶S15-A3为45∶1∶3。使用该复合发酵剂制作的酸乳感官性状优良，具有较好的风味和质地，在货架期贮藏条件下（10～15℃）后酸化程度小，可极好的满足生产需要。该文所得高自溶度复合发酵剂具有很好的生产实践指导和应用价值。
Cell autolysis could be induced by bacterial peptidoglycan hydrolases （autolysins） degrading the peptidoglycan structure of cell walls. Autolysis of lactobic acid bacteria shows direct influence on the characteristics of fermented milk products. Three high autolysis rate lactic acid bacteria, Lactobacillus delbrueckii ssp. Bulgaricus LD3-A3, Streptococcus salivarius ssp. and Thermophilus GS1-A8, and Lactobacillus lactis S15-A3 were tested to obtain a good yogurt starter. The three-factors quadratic regression orthogonal rotational composite experiment was designed to determine the effects of the three high autolysis strains on yogurt characteristics during fermentation, and the effects of mixed symbiosis and interactions were also analyzed. 〈br〉 Quadratic orthogonal rotation combination design was used to compare differences among 23 yogurt samples that were fermented by three strains of mixed starters;fresh milk was used as a culture medium. The titration acidities （Δ0T） and the organoleptic evaluation scores of the yogurts, which were stored at 10-15℃were measured after 15 days. Linear correlation analysis was also used to clarify the main factors of the three strains. The interactions of the three strains were analyzed by response surface analysis. The optimum mixed formula of the three strains was selected according to the comprehensive models. The sensory quality and shelf life of yogurt fermented by the three high autolysis rate stains mixed starters was compared with the yogurt brought from the market and yogurt fermented by the DVS starter （Danisco）. The yogurt manufacturing parameters were：Inoculation amount 10 percent, fermentation temperature 45℃to pH 4.5-4, and storage for 15 days at 10-15℃. The titration acidities were determinate at days 0, 2, 6, 10 and 15 d. 〈br〉 The most significant effect of post acidification was caused by LD3-A3, while S15-A3 could improve the flavor and organoleptic characteristics of yogurt. Results from the combination design showed that, while i
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2014年第8期272-279,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
公益性行业(农业)科研专项(201303085)(201003077)
现代农业产业技术体系北京市奶牛创新团队
关键词
发酵剂
菌
发酵
乳酸菌
自溶
酸乳
starters
bacteria
fermentation
lactic acid bacteria
autolysis
yogurt
