摘要
通过向还原脱脂乳中添加碳源、氮源及金属离子,对干酪乳杆菌(L.casei)LC2W发酵脱脂乳营养因子进行优化。在单因素试验基础上,以脱脂乳中葡萄糖、大豆多肽和MnSO4添加量为自变量,以发酵乳中L.caseiLC2W菌落总数对数值为响应值,通过三因素三水平的Box-Behnken响应面分析法,分析各自变量及交互作用对L.caseiLC2W菌落总数的影响,并对营养因子进行优化。结果表明:各营养因子对L.casei LC2W菌落总数的影响顺序为:MnSO4添加量>大豆多肽添加量>葡萄糖添加量,且MnSO4添加量与大豆多肽添加量的交互作用影响显著。各营养因子的优化参数为:葡萄糖添加量65.90g/L、大豆多肽添加量7.68g/L、MnSO4添加量13.88mg/L。在此优化条件下发酵24h后,干酪乳杆菌LC2W菌落总数可达2.6×109CFU/mL,比优化前(2.1×108CFU/mL)提高了11.38倍。
The effects of different types of added nitrogen source, carbon source and metal ion on the growth of L. casei LC2W in skim milk were evaluated to identify glucose, soybean polypeptide and MnSO4 as the best nutritional factors for L. casei LC2W. In addition, the logarithmic count of L. casei LC2W was investigated with respect to the concentrations of the selected nutritional factors. Response surface analysis based on a three-variable, three-level Box- Behnken design was employed to optimize these nutritional factors. MnSO4 concentration had the most important influence on the logarithmic count of L. casei LC2W followed by soybean polypeptide concentration; the effect of glucose concentration was the weakest. Moreover, a significant interaction between MnSO4 concentration and soybean polypeptide concentration was observed. The optimal concentrations of glucose, soybean polypeptide and MnSO4 were determined to be 65.90, 7.68 mg/L and 13.88 mg/L, respectively, yielding a L. casei LC2W count of 2.6×10^9 CFO/mL in 24 h of fermentation, which was 11.38 fold higher than before the optimization （2.1×10^8 CFU/mL）.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2012年第19期205-210,共6页
Food Science
基金
国家“973”计划项目(2010CB735705)
关键词
干酪乳杆菌
脱脂乳
营养因子
响应面法
Lactobacillus casei
skim milk
nutritional factor
response surface methodology
