Abstract: In this paper,the optimum enhancing culture of lyophilized lactobacillus bulgaricus was sieved through theorthogonality test.The viable cells number and the fermentative activity were studied to get the optimum harvesting period offermentation.The results showed that the compoments of the enhancing culture of lactobacillus bulgaricus were: MRS, wheatmalt juice 10%, tomato juice 10%, CaCO3 0.05% and lactose 1.0%.The enhancing culture had obvious enhancing effect. The viablecells number reached 3.96×1011cfu/g, OD 0.922, activity 500T and pH4.46. when the fungus in the enhancing culture culturedfor 18h.

Key words: lactobacillus bulgaricus, enhancing culture, the viable cells number, fermentative activity