The changes in pH of milk as a function of time are shown in Figure 1. During fermentation, the pH of milk decreased from ∼6.5 to ∼4.6 (Figure 1). The pH of milk decreased slowly for the first∼70 min and then decreased rapidly (Figure 1). Inoculation rate had a significant effect on the time required to reach pH 4.6 (P < 0.001) (Table 1) with the addition of more starter culture to milk resulting in a shorter time to reach pH 4.6(Table2).In yogurt gels incubated at 40 and 45.7°C, the time from inoculation to pH 4.6 was not significantly different (Table 2). At 40°C, the pH profiles for gels with 3 and 4% starter were virtually identical (Figure 1a).