Abstract:

A brown dairy drink developed in our laboratory was examined for its viable count of Lactobacillus casei in an effort to explore the effects of inoculum amount, fermentation time and solid content of raw milk on the microbiological index. Based on single factor experiments, the optimal parameters were obtained by orthogonal array design to be 6×106 CFU/mL inoculation amount, 78 h fermentation and 120 g/L solid content. Under these optimal conditions, the viable counts of L. casei reached up to 1.5 × 109 CFU/mL, which was higher than similar commercially available products.

Key words: Lactobacillus casei, dairy drink, inoculum amount, fermentation time, solid content in milk