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4. Carrasco-Pancorbo A., Cerretani L., Bendini A., Segura-Carretero A., Del Carlo M., Gallina-Toschi T., Lercker G., Compagnone D., Fernandez-Gutierrez A. (2005) Evaluation of the AntioxidantCapacity of Individual Phenolic Compounds in Virgin Olive Oil J. Agric. FoodChem. 53, 8918-8925Virgin olive oil has a high resistance to oxidative deterioration due to its triacylglycerol composition low in polyunsaturatedfatty acids and due to the presence of a group of phenolic antioxidants composed mainly of polyphenolsand tocopherols. We isolated several phenolic compounds of extra virgin olive oil (phenyl-ethyl alcohols,lignans, and secoiridoids) by semipreparative high-performance liquid chromatography (HPLC) and identifiedthem using ultraviolet, atmospheric pressure chemical ionization, and electrospray ionization MS detection.The purity of these extracts was confirmed by analytical HPLC using two different gradients. Finally, the antioxidantcapacity of the isolated compounds was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical, by accelerated oxidation in a lipid model system (OSI, oxidative stability instrument),and by an electrochemical method.5. Rotondi A., Bendini A., Cerretani L., Mari M., Lercker G., Gallina Toschi T. (2004) Effect ofOlive Ripening Degree on the Oxidative Stability and Organoleptic Properties of Cv. Nostranadi Brisighella Extra Virgin Olive Oil (2004) J. Agric. Food Chem. 52, 3649-3654The evaluation of the influence of olive ripening degree on the stability of extra virgin olive oils by the determinationof the oxidative stability index, the DPPH radical test, and the quali-quantitative analysis of phenoliccompounds, as well as the study of the variation of their sensory profiles, plays a key role in the assessment ofthe overall olive oil quality. Olives of the cv. Nostrana di Brisighella grown in the north-central Italian region ofEmilia-Romagna were picked at four different stages of ripeness and immediately processed in an experimentalmill. The polar extracts of oil samples were submitted to spectrophotometric analysis of total phenols and o-diphenols and to liquid chromatographic determination of their quali-quantitative profile (HPLC-DAD/MSD).To attain a complete description of oil samples, fatty acid composition, ultraviolet indices (K 232 , K 270 , and ∆K),free acidity degree, and peroxide value were also determined according to the European Union methods stated inRegulation 2568/91. Sensory quantitative descriptive analysis (QDA) and triangular tests were performed to establishthe influence of olive ripening degree on the resulting oil’s organoleptic properties. The evolution of theanalytical parameters studied shows that the ripeness stage of Nostrana di Brisighella olives that yields the bestoil corresponds to a Jaen index value between 2.5 and 3.5. Oils produced from olives harvested within this timeframe present a superior sensory profile accompanied by the highest possible chemical and nutritional properties.SISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it58