摘要
以脱脂牦牛乳为研究对象,滴定酸度为考察指标,利用3株具有较强发酵能力的乳酸菌:保加利亚乳杆菌(MGD1-3)、嗜热链球菌(MGB39-5)和植物乳杆菌(BM5152)为因子,研究并筛选3株菌在脱脂牦牛乳中的最佳接种量。在单因素实验的基础上,采用响应面中心旋转组合实验对影响牦牛"曲拉"发酵效果的3个因子进行了优化,建立并分析了各因子与响应值的数学模型。结果表明:在42℃条件下发酵3.5h,3个因素对发酵牦牛乳滴定酸度的影响大小依次为:MGD1-3>MGB39-5>BM5152;3株菌MGD1-3、MGB39-5、BM5152最佳组合的接种量为:5.29、7.18、6.30lgcfu/mL,在此条件下制作牦牛"曲拉",其发酵滴定酸度为71.90°T。接种等量优化组合发酵剂与牧区含菌乳清液于脱脂牦牛乳中进行验证实验,其发酵时间极显著的缩短了8.7h(p<0.01)、滴定酸度显著的提高了3.97°T(p<0.05)、活菌数极显著的增加了7.9×107cfu/mL(p<0.01)。
Skim yak milk as the research material ,titratable acidity as review indicator,with three strong fermentability lactic acid bacteria including Lactobacillus delbrueckii subsp bulgaricus（MGD1-3）, Streptococcus thermophilus（MGB39-5） ,Lactobacillus plantarum（BM5152） were researched and selected the best inoculation amount in skim yak milk. Three parameters were optimized by response surface central rotating composite design for process optimization. Finally,the mathematical model of each parameter was set up and these response values were analysed. The result showed that the influencing factors on titratable acidity of skim yak milk were MGD1-3〉MGB39-5〉BM5152 at 42℃ and fermentation lasted for 3.5h. The best inoculation amount of MGD 1-3, MGB39-5, BM5152 was 5.29,7.18,6.301gcfu/mL respectively, and the titratable acidity was 71.90°T. Inoculated equal optimized combination starter and bacteria-containing whey liquid from pastoral areas to verify test,the result showed that the fermentation time significantly was decreased to 8.7h（p〈0.01 ）,titratable acidity went up to 3.97°T（p〈0.05） and the viable count significantly was increased to 7.9×l07cfu/mL（p〈0.01 ）.
出处
《食品工业科技》
CAS
CSCD
北大核心
2014年第12期152-156,共5页
Science and Technology of Food Industry
基金
公益性行业(农业)科研专项经费项目(201303085)
关键词
曲拉
乳酸菌
优质发酵剂
响应面设计
Qula
lactobacillus
high-quality fermentation agent
corresponding surface design
