UV Light-Emitting Diodes (LEDs) and Food Safety

Safety of food processing facilities and finished products can greatly benefit from application of UV light technologies to control microbial hazards through treatments of air, nonfood and food contact surfaces, ingredients, packaging, raw and finished products. Low-pressure lamps emitting light at 253.7 nm are currently approved as a main radiation sources for treatment of juices, surfaces, or vitamin D generation with the limitations in terms of ozone production. Currently, UV LED technology is quickly extending in the UVB and UVC germicidal range as alternative to traditional UV lamps. Despite the low efficiency of UVB and UVC LEDs (approximately at 4%), LEDs are on growing trend and UVA LEDs are already being incorporated into point-of-use units to serve the defense and outdoor industries and tested for water treatment. Food safety application is the next step of UV LED adaption by industry. This chapter will review the germicidal action of UVA, UVB, UVC, and blue light, existing research, and first reported application of UV LEDs against foodborne pathogens at multiple wavelengths. Understanding of bacterial action spectra is also discussed to provide basis for optimization of the most effective treatment using single or wavelengths combinations. Considerations for UV LED treatment of fresh produce with some reported effects on quality and nutritional attributes are included.