Performance Evaluation of 3M™ Molecular Detection Assay 2 for Rapid Detection of Listeria monocytogenes in Brazilian Meat Matrices

Introduction:  Rapid Listeria monocytogenesdetection is critical to guarantee food safety and to protect food companies brands, as this pathogen contamination can result in public health problems and economic losses.

Purpose:  To verify the specificity and sensitivity of 3M^TMMolecular Detection Assay 2 – Listeria monocytogenes (AOAC OMA 2016.08) for a variery of brazilian meat matrices compared to ISO 11290-1 and 11290-2; 2004.

Methods: A total of 104 samples (raw chicken (n=20), frozen ready to eat lasagna (n=15), 2 types of sausage (n=35), breaded chicken (n=15) and hamburger (n=19)) were artificially contaminated with L. monocytogenes and analyzed with both methods. Each group was divided into a) uninoculated, artificially contaminated with b) 7.6 and c) 18 CFU/sample and d) also with a population of E. aerogenes (260 CFU/sample) as an interference microorganism.

Results: Compared to the traditional method, specificity and sensitivity of the molecular method was 100% and 92.5% respectively. In all samples that presented discrepant results between methods, the molecular method had a better performance than the reference method utilized in this study.

Significance: The alternative molecular method enabled reliable, rapid and automated detection of L. monocytogenesin meat samples.