Effect of inoculum size on goat milk fermented by Lactobacillus acidophilus and Bifi dobacterium longum

Effect of inoculum size of Lactobacillus acidophilus and Bifidobacterium longum on pH,acidity,viable count and sensory during fermentation were studied by using fresh goat milk as materials and Lactobacillus bulgaricus and Streptococcus thermophilus (2:1) as starter cultures.The results showed as follows: the optimum inoculum size of LA6 and BL were 7.0% at the same time,goat milk was fermented at 43 ℃ for 4.5 h.The pH and acidity of LA6 were respectively 4.50 and 100.0°T,the viable counts of LA6 and the total viable counts were respectively 2.90×108 cfu/mL and 1.09×109 cfu/mL.The pH and acidity of BL were respectively 4.00 and 130.0°T,the viable counts of BL and the total viable counts were respectively 7.13×108 cfu/mL and 1.11×109 cfu/mL.At the optimum inoculum size,the goat yogurts had moderate sweet and sour,no goaty favor and was tasted good.