North American Veterinary Licensing Examination (NAVLE) Practice Test

Coxiella burnetii is the organism that sets the minimum temperature needed for pasteurization of milk in the U.S. This bacterium is highly heat-resistant and can survive at higher temperatures compared to other pathogens that may be present in milk. The standard pasteurization process is designed to inactivate both pathogenic and spoilage microorganisms, and the presence of Coxiella burnetii establishes the benchmark temperature to ensure dairy safety.

The significance of this organism lies in its ability to cause Q fever and its resilience to heat, making it a concern in raw milk products. Therefore, pasteurization protocols are carefully calibrated to eliminate this pathogen effectively. As a result, the temperature and time parameters used in pasteurization are influenced by the need to eradicate Coxiella burnetii to ensure that milk is safe for consumption.

While other organisms, such as Mycobacterium bovis and Brucella abortus, are important pathogens associated with milk, they do not set the minimum temperature for pasteurization as effectively as Coxiella burnetii. Escherichia coli, although relevant in discussions of food safety, does not present the same level of heat resistance as Coxiella burnetii, making Coxiella the critical