The safety of ready-to-eat (RTE) deli meats, especially those sliced in retail establishments, may be improved by light-based surface decontamination. Conventional 254 nm ultraviolet-C (UVC) systems have strong germicidal effects but pose human-health hazards that make them unsuitable for retail use. This study therefore explores the efficacy of microplasma-based 222 nm far-UVC lamps as a safer alternative for decontaminating liquid buffer, two common food-contact surfaces (polyethylene terephthalate and stainless steel), and RTE turkey breast. In all three non-meat cases, the system achieved approximately 5-log reductions of both Listeria monocytogenes and Salmonella Typhimurium. The system also caused a 1.3-log reduction of L. monocytogenes and a 1-log reduction of S. Typhimurium on turkey breast at the highest tested dose of 786.3 mJ/cm. Color is a key quality indicator for RTE meat consumers, and treatment caused no significant change in L∗, a∗, or b∗ color values (p > 0.05) until doses reached 224.7 mJ/cm. However, higher doses could lead to statistically significant color changes. Given that far-UVC light has been deemed human-safe by other studies, the proposed system has considerable potential to improve RTE food-related safety in retail establishments, even when consumers and workers are present.
Kim Sei Rim, Corea Ventura Paola, Jin Zhenhui, Miura Mirai, Stasiewicz Matthew J, Wang Yi-Cheng
Mar 2025
Food microbiology
222 nm, Deli meats, Food safety, Listeriosis, Retail establishments, Salmonella, Ultraviolet light
Declaration of competing interest The authors declare the following competing financial interest(s): Professor Yi-Cheng Wang is concurrently collaborating with the co-founder and chief technology officer of Eden Park Illumination, Inc., Dr. Sung-Jin Park, on a Small Business Innovation Research project sponsored by the U.S. Department of Energy, which is unconnected to the present work. Dr. Park provided technical support with the far-UVC lamps used in the present work, but had no direct involvement in it, and placed no restrictions on any part of its study design; its data collection, analysis, or interpretation; or its publication.