天然促生长因子促进益生菌发酵牛骨粉钙转化的工艺优化

利用益生菌发酵牛骨粉，添加8 种天然益生菌促生长因子协同发酵牛骨粉。通过单因素试验，筛选益生菌促生长因子。采用L9(34)正交试验设计，以游离钙转化率为特征性指标，优化几种天然促生长因子的最佳组合。单因素试验结果表明：玉米汁、番茄汁、豆芽汁、白菜汁、胡萝卜汁、牛奶均对益生菌有促生长作用，除玉米汁外，发酵终止时的pH 值越低、活菌数越大，钙转化率越高。白菜汁、番茄汁、豆芽汁、牛奶最适添加量均为15%，胡萝卜汁为20%，玉米汁为5%。马铃薯汁对鼠李糖乳杆菌、嗜酸乳杆菌及两者协同发酵时均有抑制作用。正交试验结果表明：番茄汁、豆芽汁、白菜汁、胡萝卜汁4 种促生长因子协同发酵牛骨粉钙转化率的最优组合为：白菜汁18.0%、豆芽汁15.0%、番茄汁12.0%、胡萝卜汁20.0%，在该条件下钙转化率可达38.8%。

Optimization of Amounts of Added Natural Growth-promoting Factors for Fermentation of Cattle Bone Meal by Probiotics for Calcium Conversion

Natural growth-promoting factors were added to probiotic fermentation of fresh cattle bone meal for exploring the synergistic effect on the conversion rate of calcium. Single factor experiments were used to select probiotics. Meanwhile, orthogonal experiments were used to explore the optimal combination of growth factors on the basis of conversion rate of free calcium. Results indicated that corn juice, tomato juice, bean sprout juice, cabbage juice, carrot juice and milk have obvious growth-promoting effect on probiotics. Except for corn juice, the lower pH at the end of fermentation could result in the greater number of viable cells and the higher conversion rate of calcium. In addition, the optimal addition amount of cabbage juice, tomato juice, bean sprout juice and milk was 15%, whereas 20% for carrot juice and 5% for corn juice. Potato juice exhibited an inhibitory effect on the fermentation of Lactobacillus rhamnosus, Lactobacillus acidophilus, and their combinatorial fermentation. Orthogonal experimental results showed that the optimal combinatorial formula of four growth-promoting factors were 18.0% cabbage juices, 15.0% bean sprout juice, 12.0% tomato juice and 20.0% carrot juice. The conversion rate of calcium was up to 38.8% at the condition of this optimal combinatorial formula.