茶多酚对保加利亚乳杆菌生长的影响

Exploration Research on Effects of Tea Polyphenols on the Growth of Lactobacillus Bulgaricus

本文通过测定脱脂乳培养基中保加利亚乳杆菌菌体数目变化及产酸能力变化,研究茶多酚对保加利亚乳杆菌生长的影响。结果表明,高含量茶多酚对保加利亚乳杆菌酸牛乳发酵具有明显的抑制作用,低含量茶多酚抑制作用较小。随着茶多酚浓度的增加,相同发酵时间的菌体数目先增大后减小,当茶多酚添加量为2.0g/L的时候,菌体数目最多;茶多酚浓度相同时,随发酵时间的进行,酸牛乳的酸度逐渐增大,到发酵后期酸度趋于稳定,当茶多酚添加量为2.0g/L时,最终酸度最大;发酵后期,菌体形态极不稳定,大量保加利亚乳杆菌衰亡。茶多酚添加量过多,保加利亚乳杆菌产酸能力下降。而且茶多酚的颜色影响酸牛乳的色泽。

The effects of tea polyphenols on the growth of Lactobacillus bulgaricus was studied by determining the number of bacterium and the acid-producing ability.The results show that the inhibiting effect of tea polyphenols on Lactobacillus bulgaricus grown in milk decreased as the contents of tea polyphenols decreasing.As the contents of tea polyphenols increase,the number of bacteria increases but then decreases at the same fermentation time,and the number of Lactobacillus bulgaricus reaches the largest at the content of tea polyphenols of 2.0 g/L.As the fermentation time increases,the acidity of milk increases gradually at the same content of tea polyphenols at the beginning,while it is going to be stable later.When the content of tea polyphenols is 2.0 g/L,the acidity is the highest.During the late fermentation period,the morphology of Lactobacillus bulgaricus is very unstable and a large of them decays.When the content of tea polyphenols is over high,the acid-producing ability of Lactobacillus bulgaricus is decreased and the color of yogurt is affected by the color of tea polyphenols.