Growth characteristics of microorganisms on commercially available animal-free alternatives to tryptic soy medium.

The growth characteristics of a range of bacteria and fungi that are routinely used in quality control practices were compared for two representative vegetable-based tryptic soy formulations. All of the representative microorganisms grew well on the vegetable-based media and the media provided suitable recoveries of the organisms following simulated storage. Subtle phenotypic changes were observed between cultures grown on different media, but these did not significantly change the strain identification.