Rapid screening of commercial extra virgin olive oil products for authenticity: Performance of a handheld NIR device

The performance of a handheld near infrared spectroscopic device was evaluated for the rapid screening of extra virgin olive oil for authenticity. Without any sample preparation, the spectra of authentic reference extra virgin olive oils, refined olive oils, potential adulterants consisting of edible oils, extra virgin olive oil spiked with adulterants, and a total of 93 commercial olive oil products were each rapidly (10 s) measured in the transflection mode. The univariate conformity index and the multivariate supervised soft independent modeling of class analogy classification tools were used to differentiate among the various oils investigated. Out of 88 commercial products labeled extra virgin olive oil, 39 (44%) were classified as belonging to the class of authentic extra virgin olive oils. The results were compared to those recently reported for analyses carried out with a benchtop Fourier transform-near infrared spectrometer.