Abstract:

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.

Key words: probiotics, bovine bone meal, growth-promoting factor, conversion rate of calcium