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Pulsed light inactivation of Listeria monocytogenes through different plastic films

Manuela Fernández1, Susana Manzano, Lorenzo de la Hoz

  • 1Departamento de Nutrición, Bromatología y Tecnología de los Alimentos, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain. manuela@vet.ucm.es

Foodborne Pathogens and Disease
|September 9, 2009
PubMed

Insights

Pulsed light decontamination effectively inactivated Listeria monocytogenes on agar plates, regardless of whether they were wrapped in various plastic films. This technology shows promise for sterilizing packaged foods.

Area of Science:

  • Food science
  • Microbiology
  • Applied physics

Background:

  • Foodborne pathogens like Listeria monocytogenes pose a significant risk to public health.
  • Effective decontamination methods are crucial for ensuring food safety, especially for packaged products.
  • Pulsed light (PL) technology offers a non-thermal method for microbial inactivation.

Purpose of the Study:

  • To evaluate the efficacy of pulsed light decontamination for Listeria monocytogenes Scott A.
  • To assess the influence of different plastic films on pulsed light treatment effectiveness.
  • To determine the suitability of pulsed light for decontaminating packaged foods.

Main Methods:

  • Noble agar plates were inoculated with Listeria monocytogenes Scott A.
  • Plates were wrapped with 12-µm polyethylene, 48-µm polyamide/polyethylene/vinyl acetate copolymer, or 60-µm polyamide/polyethylene films.
  • Samples were treated with pulsed light at fluences of 0.175 and 0.35 J/cm(2).
  • Inactivation was quantified by counting colony-forming units (cfu/cm(2)).

Main Results:

  • Pulsed light treatment achieved a high level of Listeria monocytogenes inactivation (5-5.5 log cfu/cm(2)).
  • The presence of different plastic films did not significantly alter the decontamination efficacy of pulsed light.
  • All tested polymer films exhibited similar behavior regarding pulsed light penetration and efficacy.

Conclusions:

  • Pulsed light technology is effective in reducing Listeria monocytogenes populations on inoculated surfaces.
  • Plastic packaging materials do not impede the antimicrobial action of pulsed light.
  • Pulsed light is a viable technology for the decontamination of packaged foods, enhancing food safety.

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