Pulsed Light Inactivation of Listeria monocytogenes Through Different Plastic Films

The efficacy of decontamination by pulsed light technology through different plastic films has been assayed using Listeria monocytogenes Scott A as target microorganism. A 12-mu m polyethylene film, a 48-mu m polyamide/polyethylene/vinyl acetate-based copolymer, and a 60-mu m polyamide/polyethylene copolymer were tested. Noble agar plates were surface inoculated and wrapped with different films. Unwrapped plates were also analyzed as control. Fluences of 0.175 and 0.35 J/cm(2) were applied. Pulsed light treatment achieved the same degree of inactivation (5-5.5 log cfu/cm(2)) in either wrapped or unwrapped samples. All the polymers showed the same behavior. These results indicate that pulsed light technology could be suitable for decontamination of packaged foods.