Purpose: The occurrence, spread, growth and survival of L. monocytogenes in foods and food environments has to be controlled. Therefore, a risk-based sampling plan for the verification of the Food Safety Management System (FSMS) towards L. monocytogeneswas developed and performed for a hospital Food Service Operation (FSO).
Methods: First the classification of all used food types in various food categories, with similar microbiological ecology towards L. monocytogenes took place. Next a score system based on i) the reported epidemiological association of the food type with listeriosis outbreaks, ii) the reported prevalence of L. monocytogenes in the food types, and iii) the potential of L. monocytogenes to grow or survive during storage and/or further processing, was set up and through summation of the attributed scores, a minimum score of zero (low risk) and a maximum score of nine (high risk) could be obtained. A similar methodology was applied to identify critical sampling locations in the environment where L. monocytogenesis possibly present.
Results: The attribution of risks to the defined food categories and critical sampling locations was the basis for selection of food types and environmental samples to be taken up in the sampling plan. Seven food products (n=49) and none of the environmental samples (n=145) were found to be positive for L. monocytogenes.
Significance: The developed sampling plan can be used to improve the food safety output of the current FSMS, i.e., to control L. monocytogenes, in the FSO.