Their report published in Applied and Environmental Microbiology said blue light kills the Listeria monocytogenes pathogen as both dried cells and biofilms, especially when placed on polystyrene which is commonly used in packaging.
Biofilms, the researchers note, are normally resistant, suggesting "that blue light could effectively destroy Listeria monocytogenes."
One of the researchers, Francisco Diez-Gonzalez, said "the application of blue light for controlling microbial contamination has the potential to offer an additional technology that could complement existing methods for disinfecting surfaces in contact with foods."
For the study, researchers experimented with combinations of doses and wavelengths to find the most effective blue light approach to biofilms.
Diez-Gonzalez said that blue light has been effective as a disinfectant in hospitals and is less risky to users than ultraviolet light.
