Comparison of individual-based modeling and population approaches for prediction of foodborne pathogens growth

Authored by Jean-Christophe Augustin, Rachel Ferrier, Bernard Hezard, Adrienne Lintz, Valerie Stahl

Date Published: 2015

DOI: 10.1016/j.fm.2014.04.006

Sponsors: French National Research Agency (ANR)

Platforms: MATLAB

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

Individual-based modeling (IBM) approach combined with the microenvironment modeling of vacuum-packed cold-smoked salmon was more effective to describe the variability of the growth of a few Listeria monocytogenes cells contaminating irradiated salmon slices than the traditional population models. The IBM approach was particularly relevant to predict the absence of growth in 25\% (5 among 20) of artificially contaminated cold-smoked salmon samples stored at 8 degrees C. These results confirmed similar observations obtained with smear soft cheese (Ferrier et al., 2013). These two different food models were used to compare the IBM/microscale and population/macroscale modeling approaches in more global exposure and risk assessment frameworks taking into account the variability and/or the uncertainty of the factors influencing the growth of L. monocytogenes. We observed that the traditional population models significantly overestimate exposure and risk estimates in comparison to IBM approach when contamination of foods occurs with a low number of cells (<100 per serving). Moreover, the exposure estimates obtained with the population model were characterized by a great uncertainty. The overestimation was mainly linked to the ability of IBM to predict no growth situations rather than the consideration of microscale environment. On the other hand, when the aim of quantitative risk assessment studies is only to assess the relative impact of changes in control measures affecting the growth of foodborne bacteria, the two modeling approach gave similar results and the simplest population approach was suitable. (C) 2014 Elsevier Ltd. All rights reserved.
Tags
Cells Variability Temperature Food Listeria-monocytogenes Quantitative risk-assessment Lag time distributions Cold-smoked salmon Water activity Soft cheese