Comparison of Associative Growth and Proteolytic Activity of Yogurt Starters in Whole Milk from Camels and Cows

¹ Department of Food Sciences, College of Agriculture, King Saud University, Riyadh, Saudi Arabia 11451

Growth and proteolytic activities were studied using yogurt starter cultures incubated in pasteurized whole milk from camels and cows at 42°C as single and mixed cultures. In general, the growth of four strains of Streptococcus thermophilus and three strains of Lactobacillus delbrueckii ssp. bulgaricus was higher in cow milk than in camel milk. However, proteolysis was higher in camel milk than in cow milk. Lactobacillus delbrueckii ssp. bulgaricus LB12 in combination with streptococci had lowered pH more than did the other lactobacilli. Mixed cultures released the same amount of free amino groups as the corresponding single cultures, except for L. delbrueckii ssp. bulgaricus LB12.

Key Words: camel milk • growth • proteolysis • yogurt starter cultures

Submitted on June 15, 1995
Accepted on November 7, 1995