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Abstract
Listeria monocytogenes is a psychrotrophic pathogen that causes several foodborne outbreaks every year in the United States. In this study, a predictive model to study the growth of L. monocytogenes in egg yolk was developed and validated. The growth was studied and modeled at temperatures ranging from 0 to 45ºC. Baranyi model and Ratkowsky square root model were used to fit the growth data as primary and secondary models, respectively. Tertiary model was generated and validated using three dynamic temperature profiles of low (0-10ºC), ambient (10-25ºC) and high (25-40ºC).The primary and secondary models both provided coefficient of determination values of R2=0.99. The validation results depict that at prior physiological state of bacteria (h_o) value of 0.01, more than 80% of the prediction errors lie within the Acceptable Prediction Zone (APZ) of 0.5>Prediction Error>-1.0. These predictions can help estimate the L. monocytogenes populations due to possible temperature abuse in egg yolk.