Purpose: The purpose of this work was to determine the effect of material type, treatment time, and distance from sample to the lamp on enteric virus inactivation by pulsed light.
Methods: Various materials common in food service settings, including 304 stainless steel, nitrile disposable gloves, and Romaine lettuce squares were each inoculated with 0.1 ml MNV-1 to achieve 7-log PFU/surface. Materials were treated with pulsed light in a Xenon Steripulse XL-3000TM pulsed light treatment system for up to 10 s, at a distance of either 83 or 133 mm from the central axis of the lamp.
Results: At a sample distance of 83 mm, MNV-1 was inactivated by 1.8-, 2.6-, and 3.9-log PFU/surface, after 10 s treatment on inoculated nitrile gloves, stainless steel, and Romaine lettuce, respectively. Distance from the lamp affected reduction, with significantly more reduction (P > 0.05) achieved after 10 s treatment at the shorter distance on nitrile gloves and stainless steel, but not for lettuce.
Significance: A relatively short treatment using pulsed light is sufficient to inactivate MNV-1 on the surface of materials commonly used in food preparation. The results suggest that the technology has the potential to reduce surface viral contamination in a food preparation setting.