Growth and survival characteristics of Lactobacillus plantarum ST-III in fermented milk during storage

The characteristics of the growth of Lactobacillus plantarum ST-Ⅲ strain during the preparation of fermented milk with yoghurt starter culture at different temperatures and the survival of the Lactobacillus strain in fermented milk with various pH values during cold storage for 2 weeks were studied.No obvious growth for Lactobacillus plantarum ST-Ⅲ was observed during mixed fermentation with yoghurt starter culture neither at 37 ℃ nor at 40 ℃,The viable cells of Lb.plantarum ST-III were around the level of 5.0×106 mL-1 during the fermentation,with little increase compared with those inoculated into the milk.Furthermore,Lb.plantarum ST-III showed good survival viability in fermented milk with various pH values during cold storage for 2 weeks.No significant difference was observed on the survival viability of Lb.plantarum ST-Ⅲ among the pH value of the fermented milk in the range of 4.0 to 5.0.