Students invent award-winning sensor to assess olive oil quality.
Extra virgin olive oil sales have tripled in the United States in the past two decades, but there’s no easy way to tell if the oil inside the bottle is, indeed, extra virgin. In fact, as much as two-thirds of the extra virgin olive oil sold in the U.S. is actually much lower-grade oil, lacking the flavor and health benefits of the real deal.
Fortunately, a team of UC Davis students has built an award-winning biosensor that can quickly and inexpensively test olive oil quality. The student invention took grand prize at the 2014 iGEM (international Genetically Engineered Machines) competition, which invites the brightest minds from universities around the world to engineer solutions to real-world concerns.
“Winning was surreal,” said Simon Staley, a biological and agricultural engineering major and one of seven students on the UC Davis team. “In the finals, we were going against huge teams. We were like ‘The Little Engine That Could’.”
Current tests to assess olive oil quality are expensive, cumbersome, and provide only a crude measurement of olive oil freshness and authenticity. Rancidity — that stale taste and smell you get when oil oxidizes over time or when exposed to light, heat, or air — is the most common defect, but it’s hard to measure. Olive oil has tens of thousands of different chemical compounds, and there isn’t a single one that signifies rancidity.
“In the finals, we were going against huge teams. We were like ‘The Little Engine That Could’.”
Staley and his fellow iGEM team members — Sarah Ritz, Lucas Murray, Brian Mamsut, James Lucas, Aaron Cohen, and Julie Yeonju Song — designed an enzyme-based electrochemical biosensor that detects rancidity using a concept similar to the way a glucose meter measures blood sugar. Their palm-sized sensor could hit the market in a few years, retailing for about $80.
Initially, the biosensor will be best suited for producers, buyers, and retailers because it may be too complicated to easily test olive oil quality at home. Future iterations will be more user-friendly, including, perhaps, a version built right into bottles of extra virgin olive oil so consumers can assess quality at a glance.
“Their project has great potential,” said David Garci-Aquirre, production manager at Corto Olive Co. in Lodi, California. “A biosensor that provides an easy, affordable way to help ensure the quality of our olive oil would be an incredibly useful tool for us, for retailers, and especially for consumers. This kind of innovation will help get good oils in the hands of those trying to buy good oils.”