Pulsed UV-light is a novel technology, which is designed to inactivate microorganisms on surfaces in very short times. In this study, a pilot-scale pulsed UV-light system was designed, built, and evaluated for its effectiveness on the microbial load of whole chicken carcasses. Pulsed UV-light system consists of a total of four 40.64 cm (16 in) lamp housings facing each other in series, and a linear rail mounted along the midpoint of the chamber roof. Each chicken surface was sprayed with E. coli K12inoculum and treated at approximately 5 cm from the quartz window of the lamp housing on each side. The treatment times of 30, 45, 60, 90, 120, and 180 s were selected, based on the time each chicken would spend in one set of the systems. The log10 reductions ranged from 0.87 to 1.43 CFU/ml rinse solution after 30-s and 180-s treatments, which correspond to the actuator velocity of 78 and 13 cm/min, respectively. Energy levels for the lamps ranged from 0.24 to 0.25 J/pulse/cm~2. Sample temperatures increased significantly (p<0.05) with longer treatment times; and the temperatures ranged from 11.1 to 44.1 °C. CIELAB color parameters of carcasses after 45, 90, jnd 180-s treatments were determined. A significant (p<0.05) decrease in L* value and increasein b* value was observed after 90-s and 180-s treatments, while a* value did not change significantly (p>0.05) after treatments. The optimum treatment time was identified as 45-s treatment, which resuited in ~1 log_(10) reduction (90% reduction). Overall, the pilot-scale pulsed UV-light system was successfully designed and tested in this study to demonstrate the potential of pulsed UV-light treatment to decontaminate the surfaces of chicken carcasses without the use of chemicals.
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