Concerns over the safety of nitrite and its role in the formation of nitrosamines have aroused considerable interest in developing alternative antimicrobial agents to replace nitrite. Plant-derived antimicrobial agents could serve against food spoilage and pathogens. For the first time in this study, three semiempirical kinetic models, that is, exponential, homographic, and n-order kinetic models were established to describe the microbiological population pattern and dynamic behavior. The Escherichia coli and Salmonella enteritidis population dynamics were investigated in Frankfurter sausage as a complex food system, contained four different antimicrobial redcurrant extract (RE) concentrations (0, 0.1, 0.2, and 0.4% wt/wt) at two temperatures (4 and 25C) during 17 days storage. Furthermore, the results were compared with a neuro-fuzzy system. Although, all three kinetic models showed a reasonable prediction accuracy, homographic kinetic model was the best for predicting antibacterial effects of RE against E. coli (R2 = 0.94–1, R2 adj = 0.93–0.99, Q-squared = 0.80–0.89, and RMSE = 0.21–0.68) and the n-order kinetic model did the best in describing the kinetic pattern of S. enteritidis (R2 = 0.97–0.99, R2 adj = 0.94–0.99, Q-squared = 0.85–0.93, RMSE = 0.06–0.74). The increase in the RE concentration and temperature resulted in the increase of kinetic parameters of microbial population decline rate and extent for both bacteria, significantly. Furthermore, all the homographic model parameters (except of equilibrium population, p∞) and all the kinetic model parameters with n order (except of reaction order) the synergistic effect of temperature and concentration was clear. RE at 0.4% concentration induced 0.12 log colony forming unit (CFU)/g E. coli and 0.45 log CFU/g S. enteritidis equilibrium population (p∞) at 17th day of storage at 25C. Compared to S. enteritidis, E. coli was more sensitive to RE concentration at both temperatures.

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