嗜酸乳杆菌冻干菌粉保护剂选择的研究

Study on cryoprotectants of Lactobacillus acidophilus freeze-drying powder

为了开发以嗜酸乳杆菌为基础的各类制品,本文以嗜酸乳杆菌存活率为指标,对保护剂进行了单一和复合的筛选及配方的研究,并进行了验证实验。结果表明,单一及复合保护剂均对菌体存活率具有一定的保护作用,但复合保护剂的效果明显高于单一保护剂。最终确定出配方:脱脂乳(16.0%)、麦芽糊精(10.0%)、海藻糖(10.0%)、L-谷氨酸(1.0%)、维生素C(2.0%)、甘油(2.0%)、MnSO4(0.8%)对嗜酸乳杆菌的保护效果最佳;保护剂与细胞悬浮液最佳比例是2∶1,利用此保护剂,经真空冷冻技术可制得活菌水平在1010cfu/g的嗜酸乳杆菌冻干菌粉。

In order to develop products based on Lactobacillus acidophilus, using the survival rate of Lactobacillus acidophilus as objective, single and composite cryoprotectants were selected, the formula was studied and verified. The results showed that either single or composite cryoprotectants protected the survival rate of Lactobacillus acidophilus, but the protecting effect of composite cryoprotectants was obviously better than that of single cryoprotectants. The optimum formula of the cryoprotectant was determined as： skim milk （16.0%）, maltodextrin （10.0%）, trehalose （10.0%）, L- glutamic acid （1.0%）, vitamin C（2.0%）, glycerol （2.0%）, MNS04（0.8%）, the optimum ratio of cryoprotectant to cell suspension was 2：1. The survival rate of the freeze-dried powder of Lactobacillus acidophilus was 10^10cfu/g with this cryoprotectant.