Submitted to: Journal of Food Process Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 25, 2009
Publication Date: June 1, 2012
Citation: Huang, L., Sites, J.E. 2012. Near-Infrared Surface Pasteurization to Eliminate Listeria monocytogenes on Cooked Chicken Breast Meat Surfaces. Journal of Food Process Engineering. 35:1-15. Interpretive Summary: Listeria monocytogenes is a potentially fatal pathogen that has caused multi-state outbreaks of foodborne illness and large-scale recalls of ready-to-eat (RTE) meats in the U.S. Both FDA and USDA FSIS have maintained a “zero-tolerance” policy concerning this microorganism in RTE foods. To protect the public from being harmed by this pathogen, it is necessary to render RTE products free of L. monocytogenes before distribution and consumption. A new technology using near infrared as an intervention technology has been developed. This technology has been proven more effective than water immersion or mid-to-far infrared heating in inactivating L. monocytogenes on cooked chicken meats in the laboratory. If adopted by the industry, this technology will reduce the risk of foodborne listeriosis caused by consumption of RTE meats.
Technical Abstract: The objective of this research was to develop and evaluate a near-infrared (NIR) surface pasteurization process for decontamination of cooked ready-to-eat (RTE) meats to eliminate Listeria monocytogenes. An infrared heating device equipped with two fast-acting NIR-generating quartz lamps, an infrared remote temperature sensor, and a temperature controller was designed and assembled. Cooked chicken breast meats, surface-inoculated with a four-strain cocktail of L. monocytogenes, were used to evaluate the effectiveness of the NIR surface pasteurization process. Unpackaged samples, placed approximately 0.16 m under the quartz lamps, were subject to infrared heating to allow the surface temperature to increase to and then maintain at a set-point temperature. The average come-up-time was 79.3 (12.8), 133.1 (17.8), and 156.2 (32.1) s, respectively, for the set-points of 62, 68, and 75 C. On average, the overall rates of bacterial inactivation were 0.35, 0.89, and 1.6 log-cycles/min for the samples treated at 62, 68, or 75 C, respectively. In contrast, the bacterial inactivation rates were only 0.21, 0.53, 0.63, or 0.95 log-cycles/min for samples submerged under hot water maintained at 62, 68, 75, or 85 C, respectively. With the same treatment temperature at 75 C, more bacteria were killed by NIR and the total heating time was reduced by almost 50 percent, when compared to a previous study using mid-to-far infrared heating to treat RTE meat. NIR surface pasteurization process was convincingly more effective than the hot water immersion process or mid-to-far infrared heating for surface-decontamination of cooked chicken meats to eliminate L. monocytogenes.