Blue LEDs, once confined to the world of digital displays and Blu-ray players, have just found a new calling: food preservation. New research at the National University of Singapore shows the potential of using blue LEDs as a chemical-free method to kill bacteria that lead to spoilage.

Earlier this year, public concern about artificial preservatives pushed fast-food restaurants like McDonald’s, Subway, and Panera to seriously rethink the ways they keep their food fresh. Using blue LEDs could potentially kill the same bacteria that preservatives do without any of the scary, outrage-rousing chemicals.

The researchers looked at the effect of blue LED exposure on three of the major colonies of bugs that cause food to rot and stomachs to turn: Listeria, E. coli, and Salmonella. Their paper, published in the journal Food Microbiology, showed that the blue lights succeeded in inactivating the bacteria, with even better results in cold temperatures and acidic conditions. Foods like fresh-cut fruit, chilled meats, and ready-to-eat seafood, like sushi and lox, could all someday benefit from the pathogen-killing lights.

The scientists still need to do follow-up studies using bacteria in actual food just to make sure the blue LEDs don’t somehow cause the food to deteriorate. But the basic technology is there, and the team hopes it’ll someday become a common sight in food courts and supermarkets.

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The dudes who invented blue LEDs won the Nobel Prize in physics last year and might have foreseen their application to white lasers, but they probably didn’t see their work taking on the food world. Are LED’s champions ready to take on the chemical industry?

Yasmin is a writer and former biologist living in New York. A Toronto girl at heart, her writing also appears in The Last Magazine and SciArt in America. You might recognize her as a past host of Scientific American's YouTube series.