The increasing popularity of the Mediterranean diet means that the production of high quality extra-virgin olive oil is a booming business. The oil produced in Italy is renowned worldwide for its distinctive taste and nutritional benefits, being low fat and rich in anti-oxidants.
But cheaper, low-grade oils, misleadingly packaged as expensive products made in Tuscany, are flooding the market, threatening the livelihood of genuine producers and duping consumers.
Now, a Loughborough University researcher has teamed up with scientists from Italy to develop a unique optical fingerprinting system that can detect extra virgin oil from the fakes.
The unique optical fingerprinting system was developed in Loughborough University’s Department of Electronic and Electrical Engineering, using spectroscopy, a technique with widespread sophisticated medical applications, such as studying the concentration of oxygen in blood.
Peter Smith, Professor of Photonics Engineering, explains: “It’s very difficult to spot significant differences between different types of oils just by looking, but this new light scattering and absorption technique provides a very sensitive indicator. Having illuminated the sample with white light, we can see how much light of each colour shines through the sample and how much is scattered. By carefully studying how the absorbed and scattered spectra become brighter or darker at each wavelength, we can determine the oil’s grade (virgin or extra-virgin) and its origin.”
He continues: “We have been able to produce for the very first time a distinctive ‘optical fingerprint’ that tells us exactly where the olive oil is from and the process by which it has been made. Plotting these fingerprints on a 3D map reveals distinctive clusters according to oil type. This allows for reliable, low-cost analysis that can easily distinguish the frauds from the genuine extra-virgin articles. The technology can be used to test the authenticity of other high value food and drink products, such as wine and beer.”
The research was carried out in partnership with Italy’s CNR Institute for Applied Physics in Florence, and the CNR Trees and Timber Institute in Sesto Fiorentino, as part of a European project called OPTIMO.