The number of high-profile Listeria monocytogenes recalls and outbreaks seems to be increasing. This suggests that some food manufacturers may not have an adequate Listeria control program.

No matter where or how the risk to pathogens is being introduced, testing is essential to validate each of those control efforts before use and routine verification testing is essential to ensure that controls are working when deployed.

The need for speed is a double edge sword.

There are test platforms available that promise quicker time to result; however, users experience high rates of false positives and high rates of false negatives using such solutions. Furthermore, many processors deploy complicated sample pooling protocols that by design will reduce odds of finding a positive test result. Together, these judgment errors can result in release of contaminated product, give users a false sense that their control programs are working, and may increase liability due to gross negligence risk.

This presentation highlights some common sampling and testing practices and highlight risks associated with their use.

Featured Presenter

Douglas L. Marshall, PhD, CFS

Doug is the Chief Scientific Officer with Eurofins Microbiology Laboratories. He is a frequent volunteer and consultant to trade associations, NIH, WHO, FAO, USDA, and other government agencies and private companies. With over 250 publications and nearly 300 invited presentations, his scientific research and outreach interests focus on improving the microbiological quality and safety of foods.

Doug is a Fellow and former member of the Board of Directors of the Institute of Food Technologists, former Chair of the International Food Science Certification Commission, and former member of the Board of Directors of the American Spice Trade Association.

Read Doug’s full bio: Douglas L. Marshall - Eurofins USA

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