Modeling survival curves of Anisakis L3 after isothermal heat treatments at lethal temperatures

• Published in: Food control 2023-12, Vol.154, p.109975, Article 109975
• Main Authors: Guan, Aiyan, Usieto, Marina, Sánchez-Alonso, Isabel, Arcos, Susana C., Careche, Mercedes, Otero, Laura
• Format: Article
• Language: English
• Subjects: anisakiasis; Anisakis; Anisakis larvae; fish; Fish cooking; Food safety; heat; Isothermal survival curves; kinetics; Modeling; public health; temperature; Thermal inactivation; viability
• ISSN: 0956-7135
• DOI: 10.1016/j.foodcont.2023.109975

Even though anisakiasis is considered, nowadays, a significant threat to public health all over the world, no attempt has been made up to date to mathematically describe the thermal susceptibility of Anisakis larvae in the third stage (L3). To fill this gap, in this paper, more than 10,000 free (non-encysted) Anisakis L3 were individually heat treated in a thermal cycler at temperatures between 44 °C and 61 °C for different exposure times. After heat exposition, viability was assessed in each larva, survival curves at isothermal conditions were derived, and the effectiveness of four kinetic models (fundamental kinetic model, Mafart model, and probit and logit models) in describing these curves was tested. Evaluation of larvae viability after heat exposition revealed sigmoidal survival curves that increased their steepness with temperature. Of the four models tested, the Mafart model was the one that best fitted the data only differing from the observed survival ratios by 0.12 units on average. Validation experiments performed at temperatures different to those used to create the model corroborated its predictive capacity. Future efforts should be focused in predicting larvae viability at non-isothermal conditions as those occurring during fish cooking. •Anisakis larvae were individually heat treated and their viability assessed.•Lethal times required to kill 99.65% of the Anisakis population were estimated.•Survival curves at isothermal conditions were derived at 46 °C–55 °C.•A model for prediction of larvae viability after heat exposition was obtained.