Effects of UVC light-emitting diodes on microbial safety and quality attributes of raw tuna fillets

Abstract

Ultraviolet light-emitting diodes (UV-LEDs) have become widespread for decontaminating the surfaces of food products and their packaging as a safer alternative to traditional mercury-vapor based UV lamps. This study aimed to investigate the effect of UVC- LEDs (275 nm) on the inactivation of foodborne pathogens and quality attributes of raw tuna fillets. Raw tuna fillets inoculated with cocktails of Salmonella Typhimurium, Listeria monocytogenes, and Escherichia coli O157:H7 were exposed to UVC-LEDs at 500-4000 mJ/cm2. UVC-LED treatments of single-layer tuna fillets at a dose of 4000 mJ/cm2 resulted in 1.31-, 1.86-, and 1.77- log reduction of S. Typhimurium, L. monocytogenes, and E. coli O157:H7, respectively. The pH value, water-holding capacity, metmyoglobin, texture, and color characteristics of tuna fillets were not significantly (p > 0.05) changed following the UVC-LED treatment at radiation doses up to 4000 mJ/cm2. Nonetheless, the UVC-LED irradiation led to increased levels of lipid oxidation in tuna fillets. Overall, the present study demonstrates that UVC-LEDs are a promising technology to reduce microbial flora and maintain the physicochemical properties of fish products.