PVP K-30对嗜酸乳杆菌的冻干保护研究

Protection of PVP K-30 to freeze-dried Lactobacillus acidophilus

聚乙烯吡咯烷酮K-30,简称PVP K-30,是一种新型的食品安全添加剂,在食品产业中受到广泛关注。以嗜酸乳杆菌冻干存活率为衡量指标,对包括PVP K-30在内的13种冻干保护剂进行了单因素保护效果的比较,并对筛选的5种保护剂进行L16(45)多因素复合实验,结果表明,13种单一保护剂对菌体存活率均具有一定的保护作用,复配保护剂的效果明显高于单一保护剂;PVP K-30可明显增强脱脂乳、海藻糖的保护能力;以4%PVP K-30、20%脱脂乳、6%海藻糖、0.5%谷氨酸钠和4%甘油组成的复配保护剂效果最佳,可使嗜酸乳杆菌真空冷冻干燥后存活率达到93.33%。

Polyvinyl Pyrrolidone K-30,abbreviated to PVP K-30,as a new safety food additive,is extensively used in food domain.Taking the survival rate of Lactobacillus acidophilus as measure,research on freeze-dried protective capability of PVP K-30,comparing with other 12 types of common used cryoprotectants,four cryoprotectants were gotten to compound with PVP K-30,L16（45）orthogonal test of five cryoprotectants were performed.The result shows that the protecting effect of composite cryoprotectants was obviously better than that of single cryoprotectant;PVP K-30 can markedly enhance protection capacities of skim milk and trehalose.The optimum formula of the cryoprotectant was determined as：PVP K-30 4%,skim milk 20%,trehalose 6%,sodium glutamate 0.5%,glycerol 4%,protecting Lactobacillus acidophilus with the survival rate up to 93.33%.