FIGURE 2.

The addition of peptone allows the growth of Propionibacterium freudenreichii in cow’s milk ultrafiltrate (MUF) and in soymilk ultrafiltrate (SUF). P. freudenreichii CIRM-BIA129 was cultivated in MUF [cow’s milk ultrafiltrate supplemented with casein peptone (□)], or in SUF [soymilk ultrafiltrate supplemented with soy peptone (■)], in a pure culture. The growth of propionibacteria was monitored by following turbidity (OD at 650 nm) during incubation at 30°C (A) and acidification was also monitored (B).