Modeling the Growth of Pseudomonas putida and Salmonella enterica in Raw Ground Poultry Meat Subjected to a Dynamic Temperature Deviation

This research was conducted to develop and validate growth models for Pseudomonas putida and Salmonella enterica in raw ground poultry meat. Separate experiments included similar experimental methods by inoculating bacteria into irradiated raw ground chicken meat; subjected to isothermal temperatures (P. putida at 5-35°C and S. enterica at 7-45°C) within the entire growth temperature range to simulate temperature fluctuation and possible deviations. Microorganisms were quantified and fitted with the Baranyi equation using USDA-ARS Integrated Pathogen Modeling Program to create a primary model and yield a low RMSE value for both microorganisms (0.065-0.519), and the maximum specific growth rate (μmax) to create the secondary model. Secondary model used the Ratkowsky square root equation resulting in RMSE values for P. putida (0.05) and S. enterica (0.08), indicating high reliability. Tertiary models were validated with dynamic sinusoidal low and high temperature profiles: P. putida (5-20°C and 15-35°C) and S. enterica (7–25 °C and 20–45 °C). Validated tertiary models demonstrated a strong goodness-of-fit between observed data and predicted values.