Quality of virgin olive oil from territorial quality label "Les Garrigues"DO (Lleida. Spain) along the 1995/96 harvest

The Garrigues territorial quality label (Les Garrigues D.O.) is located in the southern part of Lleida (Catalonian. Spain). The most oil produced in t his D.O. corresponds to extra virgin classification and it has a distinctiv e sensorial quality, as a consecuence of olive cultivar (<< Arbequina >> cv ) and the careful elaboration of oil. The new cultural technologies applied to the olive tree cultivar and the new technologies of olive oil extractio n have made necessary the study of oil composition and quality during conse cutive harvests, to know if the quality could be afected. The objective of this work is the characterization of virgin olive oils (67 samples from 13 olive mills) during the 1995/96 harvest. Analytical controls show that the mean acidity index is 0.17% in oleic acid , the mean peroxide value is 6.9 meg oxygens active/kg of oil and the mean K-270 Of 0.21; these quality parameters fulfill the policy values of << Les Garrigues >> D.O. The mean polyphenol content is 152 ppm expressed as cafe ic acid, with a great variability among olive mills. As harvesting time pro gresses, the concentration of pigments in olive oil decreases. The concentr ation of chlorophyl and that of carotenoid pigments at the begin of the har vest is 15 and 12.6 mg/kg of oil respectively and at the end of the period they are 6 and 4.6 mg/kg of oil respectively. The oil color, expressed as v isual ABT index and the chromatic ordinates CIELAB, lies within the yellow zone and does not vary along the harvest season.