Modeling the fate of Listeria monocytogenes and Salmonella enterica in the pulp and on the outer rind of Canary melons (Cucumis melo (Indorus Group))

- Growth parameters of L.m. and S.e. on rind and pulp of Canary melons was studied.
- Growth parameters of L.m. and S.e. on rind and pulp were not different at 15-35 °C.
- L.m. showed the shortest lag times and S.e. presented the fastest growth rates.
- L.m. and S.e. can quickly grow on outer rind and pulp of Canary melons.

The aim of this study was to develop a predictive model for the growth of L. monocytogenes and Salmonella in the pulp and the outer rind of Canary melons (Cucumis melo L.) as a function of temperature. The experiments of L. monocytogenes and Salmonella enterica showed that the former can grow in all temperatures tested, from 5 °C to 35 °C, both on the outer rind and in the pulp of melons while the latter did not grow when the outer rind and the pulp of Canary melons were stored at 5 °C. There was no significant difference (p > 0.05) regarding the growth kinetic parameters [growth rate (μ) and lag time (λ)] when the pathogens were inoculated on the outer rind and pulp following storage between 15 and 35 °C. Secondary models (Ratkowsky model) were able to describe the influence of temperature on μ and λ for both microorganisms on the outer rind and pulp of Canary melons. This study adds quantitative data to the literature on the fate of L. monocytogenes and S. enterica in Canary melons and reveal that pulp and the outer rind of this fruit comprise substrates that support the growth of both pathogens in a wide range of storage temperature.