Inactivation of Vibrio parahaemolyticus by intense pulsed light treatment

In this study, the antimicrobial efficacy of intense pulsed light (IPL) treatment against Vibrio parahaemolyticus was investigated using various operational parameters. The effects of voltage (700–1,000 V) and distance (4–12 cm) on bacterial inactivation were systematically evaluated, and energy density measurements and kinetic modeling were performed to optimize the treatment conditions. Total energy density and UV-C percentage increased significantly with higher voltage, achieving the maximum UV-C percentage of 15.69% at 1,000 V. Surface temperature increases remained below 1°C across all treatment conditions, confirming the nonthermal nature of IPL processing. The inactivation efficiency increased substantially with higher voltages and shorter treatment distances. A reduction exceeding 8 log CFU/mL was achieved after 200 μs treatment at 1,000 V and 4 cm distance, whereas significantly lower reductions were observed at reduced voltages or extended distances. Bacterial survival curves were accurately described using the Double-Weibull model (R2>0.98). The 4D value (time required for 99.99% reduction) decreased significantly from 556.94 μs at 700 V to 58.28 μs at 1,000 V. These findings demonstrate that IPL is a highly effective nonthermal technology for controlling V. parahaemolyticus contamination in seafood processing.