Research of lactobacillus acidophilus freeze-dride impact factor

Traditional lactic acid bacteria fermentation process is complicated and easy to be polluted.At present,the freeze drying techniquewas used to prepare DVS powder of lactic acid fermentationagent.However,Bacteria lyophilization's time and freeze-drying protectiveagent selection directly affected the survivalrate and survival time of lactic acid bacteria in freeze drying.The growth curve of lactobacillus acidophilus was studied,sucrose,lactose,glycerin,vitamin C,sodium glutamate,maltodextrin,skim milk were used as freeze-dried agents.The results showed:①the test termination condition of fermentation was when OD410nm was up to its biggest 0.511at 100°Tand pH 4.8.The best freeze-driedprotective agent was the composition of 5% dextrine、2% VC、5% glycerol.Under the above conditions,the living bacterium numberof lactobacil lus acidophilus in freeze-driedpowder was 2.34×1010cfu/g.