Thanks to its nutritional value, its cosmetic and therapeutic properties, virgin olive oil (VOO) is becoming as a food in the

Therapeutic efficiency of virgin olive oil components, like antioxidants, has been proved. Moreover, the adulteration of virgin olive oil by the refined olive oil is a known fraudulent practice in non formal markets in some developing countries. In Morocco, there is a need of non expensive and fast tool to quantify the adulteration of virgin olive oil by the refined one. That is why we used a coupling between Fourier transform middle infrared spectroscopy, as a non expensive analysis technique, and Euclidean distance and hierarchical ascending cluster methods.
Virgin olive oil was extracted from ''Picholine'' cultivar olives in Tadla Azilal area, in Morocco. Fourier transform middle infrared spectroscopic parameters of prepared mixtures of virgin and refined olive oils have been used to determine the adulteration. The result of the Euclidean Distance concerning such an adulterated virgin olive oil has allowed the quantification of the adulteration percentage. The results of the hierarchical ascending cluster could provide a fast classification of virgin oil oils. Thanks to its rapidity and relatively low cost, coupling between middle infrared spectroscopy and chemometric methods would be an efficient tool to ensure authentication and traceability of virgin olive oil.