Study on Storage of Lactobacillus acidophilus and Bifidobacterium longum Isolated from Baby Faeces at Normal Temperature

Objective:By testing different protective agent formulas,to explore the feasible method of keeping high activity of two kinds of probiotics(Lactobacillus acidophilus and Bifidobacterium longum) isolated from baby faeces at normal temperature.Methods:The strains with high specific activities and stabilities were conserved with various protective agent formulas which were prepared as the experimental method of uniform design.Then,the viable cell counts of the probiotics were measured at different time point and the best ratio of protection agent compositions were got by data process.Results:The best ratio of protective agent formulas of the Lacidophilus 10A31 was:trehalose:glutamic acid:asparagic acid=5:24:24,while the B.longum 11A11 was:trehalose:glutamic acid:malt dust=34:11:10.After adding the best protective agent,the viable cell counts of L.acidophilus 10A31 were above 3.87×10~9 CFU/g after 200 days' storage and viable cell counts of B.longum 11A11 were above 1.53×10~9 CFU/g after 160 days' storage.Both of them still had high activities.Conclusion:The L.acidophilus and B.longum can be stored at room temperature for 160 days with the best formula.