Predicting inactivation of Anisakis L3 after non-isothermal heat treatments: Impact of thermal conditions during and after cooking

Accurately predicting the thermal inactivation of Anisakis larvae during cooking is essential to ensure food safety while preserving the quality of fishery products. In a previous study, we developed a Weibull-based model that successfully described larval inactivation under isothermal conditions up to 55 °C. However, real cooking processes typically involve dynamic temperature profiles with gradual heating and cooling phases. To estimate Anisakis viability under realistic processing conditions, a predictive model capable of integrating the entire non-isothermal thermal history is required. To do so, in this study, we implemented the differential form of the Weibullian model and explored two alternative formulations to describe how thermal resistance changes with temperature: a single log-quadratic equation and a more flexible piecewise log-quadratic function. All model parameters were optimized using 98 previously published non-isothermal inactivation experiments and validated against 26 independent treatments. While the piecewise model provided a slightly better fit during training, the single log-quadratic formulation showed superior predictive accuracy ( 0.9782, 0.0497) and was selected for further use. The validated model was used to investigate how heating and cooling rates affect larval inactivation. Simulations revealed that slow heating and cooling significantly increase lethality, even at mild temperatures. These predictions were consistent with experimental observations and underscore the critical influence of thermal history beyond peak temperature alone. This modeling approach provides a robust framework for designing safe, quality-preserving cooking protocols and offers valuable support for risk assessment and regulatory guidance in seafood safety. • Model to predict Anisakis L3 inactivation at non-isothermal conditions is implemented • Differential form of Mafart- & log-quadratic secondary models show high accuracy • Slow heating/cooling increases lethality even at mild temperatures • Thermal history, not just peak temperature and holding time, determines survival • Model supports safer, quality-preserving fish cooking protocols