Purpose: The aim of this paper was to illustrate how microbiological criteria (MC) for Listeria monocytogenes in cold-smoked salmon can be established based on risk-based metrics (Performance Objectives, PO). The example was achieved with the use of the Baseline software tool (www.baselineapp.com).
Methods: For simplification purposes, PO was set after product elaboration in the industry. The initial product contamination was 1.5 log CFU/g, storage at 4ºC during 4 days (96 h) and commercial salmon formulation was assumed: 2 ppm phenol and 3 mg/100g NaCl. The PO was set as no more than 5% of units in the lot would have a concentration above 3 log CFU/g. With this information an MC was established that just complies with the PO (95% CL).
Results: Growth increase of L. monocytogenes was 1.78 log CFU/g at the end of the storage period. The standard deviation of the product in such a way the PO will be complied [P (log CFU/g >3) < 5 % of the samples conforming the lot] was 0.74 log CFU/g. The MC is a practical tool to verify whether individual batches/lots meet the PO by taking samples from such batches/lots for microbiological analysis. Considering a microbiological limit of 2 log CFU/g, MC to allow lot rejection at 95% CL was derived through the Baseline software tool as n=7; c=0; m=2 log CFU/g.
Significance: The use of the Baseline software offers a flexible graphical user interface where models can be incorporated and/or evaluated as well as new sampling plans. This information may be used to evaluate the overall effectiveness of applied interventions by risk managers or food operators.