Optimization of cryoprotectants production process for direct vat set Lactobacillus plantarum with high- yield of γ- amino butyric acid

A cryoprotectant formulation for Lactobacillus plantarum Lp- Lw-131 was optimized using the orthogonal experiment.The optimum cryoprotectant formulation was dried skim milk 15.0g / L,sucrose 20.0g / L,maltodextrin25.0g / L,glycerine 3.0m L / L. The survival rate of Lactobacillus plantarum with the addition of the optimized cryoprotectant formulation after freeze- drying was 75.3%.The electron microcopis observations showed that the protection agent chosen has good protection function on the bacteria.