Microcalorimetry constitutes an analytic tool to register the heat effects produced by the metabolic processes taking place in a bacterial culture. Since these depend on the nutrients supplied in the media, microcalorimetry allows conclusions to be drawn about the nature and quality of the culture medium when using a standard germ. Taking Columbia Broth as an example, we showed that faulty weighing of the dry substrate, incorrect pH or overheating during the dissolving or autoclaving procedures could be detected by the use of the microcalorimetry. A microcalorimetric assessment to compare media of the same name produced by different manufacturers was carried out and significant differences were observed. We consider this microcalorimetric technique to be a valuable tool in the assessment of liquid culture media.