In a delicious turn of events, scientists succeeded in taking the optics of olive oil to create the first-ever microlaser made entirely from edible materials. If commercialized, they could offer an easy and safe way to monitor food or medications from inside your body.

The technology, introduced earlier this month in the journal Advanced Optical Materials, exploits an interesting tendency for droplets of common cooking oils, which emit a photon of light when subjected to a certain amount of energy. Arrange multiple droplets in a room full of mirrors, and together they shine more brightly—like a concentrated beam of light. 

The researchers tested more than a dozen different types of materials—sunflower oil, cooked butter, plain water, and more—to see which would generate the cleanest laser. And the winner was olive oil. 

One prominent component of olive oil is chlorophyll, the molecule most commonly known to make plants green. In this case, the chlorophyll molecules, trapped in the sticky surface of olive oils, generated photons in a chain reaction of sorts, transforming the droplet of olive oil into a laser. 

The brightness of the chlorophyll changes in accordance with the size and density of the oil droplets, making the laser highly sensitive to environmental conditions, according to the study. For example, adding it to different dishes of food and observing changes in the  laser allowed the researchers to measure things such as sugar concentration or acidity

What’s more, the researchers were able to encode data within the droplets akin to the lines of a barcode, into a peach compote. Surprisingly, the data—the specific date of April 26, 2017, which happens to be the first international Stop Food Waste Date—remained intact for over a year, demonstrating the microlaser’s potential to safely carry information, such as the identity of a manufacturer or an expiration date. 

“Since this is the first such study, there are many possibilities for developing various edible lasers and their applications, which could ultimately find their way to everyday use,” the study authors concluded.