Modeling the combined resistance to microwave treatments and salt conditions of Escherichia coli and Staphylococcus aureus.

This study focuses on evaluating the combined effects of microwave irradiation and sodium chloride (NaCl) concentration on the inactivation kinetics of the bacteria Escherichia coli and Staphylococcus aureus. Using three NaCl concentrations (0.5%, 3.5%, and 8.5% w/v) and three microwave power levels (450, 600, and 800 W), microbial survival was modeled with a one-step Weibull equation accounting for dynamic temperature profiles during treatment. Results showed that higher microwave power and lower salt concentrations enhanced microbial inactivation, with E. coli being generally more susceptible than S. aureus, which exhibited greater resistance and variability. The developed predictive models were validated using ultra-high temperature (UHT) milk and demonstrated reasonable accuracy, suggesting their potential utility as decision-making tools for optimizing microwave treatments to ensure food safety.