Modelling cross-contamination in food processing

Food handling and cross-contamination during food processing may have a large impact on the microbial contamination of foods and are, therefore, of crucial importance for food safety. As a consequence, microbiological risk assessment requires the development of suitable models describing the effect of these processes, but traditionally, they fall outside the scope of predictive modelling. Unlike growth or inactivation, cross-contamination and transfer of microorganisms cannot be properly described with log-linear models. The consequences of cross-contamination are best predicted by applying models that include the dynamics involved in the process. Only a better understanding of those dynamics, related to environmental processing and food handling behaviour, will give the necessary perspective to develop models able to describe and predict efficiently the events inherent in the cross-contamination phenomena. This task can be challenging, since events related to cross-contamination are quite complex and are still not completely understood. Data may be scarce, definitely for realistic conditions with low numbers of microorganisms involved.