Listeria growth under diffusional limitations in synthetic meats

Abstract

SummaryPhysicochemical properties of meat products make them susceptible to contamination by several pathogens such as Listeria monocytogenes. As reference of L. monocytogenes behaviour, the evolution of Listeria innocua growth was monitored at different positions within a κ‐carrageenan synthetic meat and visualised by scanning electron microscopy (SEM). Microbial growth was also determined in a liquid medium, prepared with the same nutrients as the solid phase, and the effect of oxygen concentration, a fundamental parameter in meat preservation, was studied. To simulate microbial behaviour in the solid, results of kinetics in broth were incorporated to a diffusion‐reaction model that considers growth kinetics as a function of the local oxygen concentration. Data from the model have been then discussed, taking into account experimental data and SEM observations. This model, useful for food safety purposes, has been shown to provide a reasonably good simulation of experimental data in the structured synthetic meat.