Effect of Total Inoculum Size Containing Lactobacillus acidophilus or Lactobacillus casei on Fermentation of Goat Milk

In order to obtain the optimum inoculum size of goat milk fermented by probiotics, the total inoculum size containing L. acidophilus or L. casei on pH, acidity and viable counts and sensory during fermentation were studied on the basis of S. thermophilus and L. bulgaricus as starter cultures. The results showed as follows: the optimum inoculum size of L. acidophilus and L. casei were all 7% and goat milk was fermented at 39°C for 4.5 h. The pH, acidity, the viable counts of L. acidophilus and the total viable counts were respectively 4.48, 91°T, 1.60×107 cfu/mL and 1.69×109 cfu/mL. The pH, acidity, the viable counts of L. casei and the total viable counts were respectively 4.38, 96°T, 2.80×108 cfu/mL and 2.20×109 cfu/mL.