A Quasi‐Chemical Kinetics Model for the Growth and Death of Staphylococcus aureus in Intermediate Moisture Bread

The “quasi‐chemical” kinetics model accounts for all 4 phases of the microbial lifecycle based on a proposed series of chemical rate equations. The model fits continuous growth‐death kinetics for Staphylococcus aureus in intermediate moisture bread in various conditions of water activity, pH, and temperature. Growth rates evaluated using the quasi‐chemical model are compared with values obtained with the Gompertz model. Kinetics data obtained with the quasi‐chemical model are integrated with a probabilistic approach to estimate the boundary between growth and no‐growth conditions. Continuous modeling of microbial growth/death kinetics in actual foods advances predictive modeling that conventionally separates growth and death models.