Researchers from Clemson University have launched two studies aimed at preventing listeria contamination in packinghouses.

According to the Center for Produce Safety, the first project, "Preservation of stone fruits by spray application of edible coatings with antimicrobial properties," examines coatings that could reduce Listeria monocytogenes populations on fruit without affecting storability, appearance, or taste.

The second and more recent funded project, "Preventive sanitation measures for the elimination of Listeria monocytogenes biofilms in critical postharvest sites," looks at difficult-to-sanitize micro-environments within a packinghouse where bacteria may reside that could serve as reservoirs. In addition to identifying problem areas, the researchers plan to test commonly used sanitizers to determine optimal concentrations and contact times to inactivate biofilms.

Both projects are being led by Kay Cooksey, Ph.D. and Cryovac Endowed Chair, with co-principal investigator Claudia Ionita, Ph.D. and post-doctoral researcher. The two researchers, both with Clemson University's Food, Nutrition and Packaging Sciences Department, say the arrangement yields "good synergy" because each brings different expertise to the table. Cooksey has a packaging science and food technology background, whereas Ionita is a microbiologist.

Previous CPS-funded research by Mary Anne Amalaradjou, Ph.D., with the University of Connecticut, found Listeria monocytogenes does indeed survive on the surface of peaches and nectarines. Cooksey intends that her project results will offer the fresh fruit industry another hurdle technology that can be used to help reduce those risks. "We're hoping to give them an additional margin of safety," she says.