Assessment of the quality of virgin olive oil of the Moroccan Picholine variety

This work examines the effect of olives pitting on virgin olive oil quality. It compares physicochemical and gustative quality of oils obtained from whole olives and pitted ones. Oil analyses concerned free acidity, peroxide index, UV extinctions at 232 and 270 nm, total phenolics content and fatty acid composition. Degustation, by a panel composed of 54 students, used triangular discrimina-tive test to distinguish between whole and pitted olive oils taste; also, panel was invited to give personal preference for one of the two types of olive oils. Physicochemical data demonstrated that all oil samples are classed as extra virgin olive oil category. Data comparison of paired samples noticed no significant difference between pulp olive oil and whole olive oil. Pitting olives caused low but non-significant increase (P = 0,097) of total phenolics content and had no effect on fatty acid composition. Significant taste difference was noticed between whole olive oil and pulp olive oil (P = 0,029 < 0,05) and 39 % of panel members exhibited taste preference towards olive pulp oil.
Keywords: Olive pulp oil, physicochemical characterization, chemical quality, gustative quality, triangular test, taste preference.