A new method of labeling olive oil could prevent fraud in the supermarket. By “labeling” oils with unique tags of DNA, new research suggests (paywall), regulators can make certain that supplies of olive oil—and other oils, including fuels and cosmetic ingredients—stay pure.
There’s a real need for these high-tech oil tags: A study (pdf) led by Edwin Frankel, former professor at University of California’s Department of Food Science and Technology, found that as much as 69% of “extra virgin” olive oil sold in the US doesn’t meet the standards of the term. While some of this substandard product might just be poorly made, some is adulterated with cheaper vegetable oils.
Injecting high-grade olive oil with a unique DNA signature could be the solution. The packets of synthetic DNA, developed by professor of chemistry and bioengineering at ETH Zurich Robert Grass, are coated with silica and attached to tiny pieces of iron. The silica makes them resilient, so they can be dropped into oil that might change temperature or be exposed to light or chemicals. And since the iron magnetizes the DNA packets, regulators can easily extract them for testing using a magnet. The process of tagging, Grass said, should only cost about 2 cents per liter of product. And regulators could check the concentration of tags in the oil to see if some of it has been replaced by cheaper product.
Will people eat these nanoparticles on their bruschetta? Grass thinks they should. Silica particles are present in ketchup and orange juice, he said in a press release, and the iron used is an approved food additive. On the other hand, if olive oil is adulterated, you have no idea what’s in it. The addition of particles you’ll never see or taste, he says, could assure you of your food’s safety and value.