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18 Pags.- 7 Tabls.- 1 Fig. The definitive version is available at: http://www.innovhub-ssi.it/web/stazione-sperimentale-per-gli-oli-e-i-grassi/rivista-italiana-sostanze-grasse ; [EN] The objective of this work was to follow the maturity of the olives in a commercial Arbequina super-high density orchard and to study the evolution of the olive oil quality. For this objective, the physicochemical, nutritional and sensory parameters were studied. The free acidity was found to be similar during ripening whereas the peroxide index and K232, K270 decreased. The total phenol content and oxidative stability showed a similar trend. First, it increased and then decreased. α-tocopherol, saturated fatty acid and pungency decreased. The polyunsaturated content increased while the MUFAS/PUFAS ratio decreased. In 2010, the crop maturity was quicker, and the maturity indexes were higher than in the 2009 crop for the same picking date. Even in the same orchard, the maturity is changing in each crop season. For this reason, it is necessary to choose the optimal harvesting date. ; [IT] L'obiettivo di questo lavoro è stato quello di seguire la maturazione delle olive Arbequina in un frutteto commerciale di super-alta densità e di studiare l'evoluzione della qualità dell'olio d'oliva. Per questo obiettivo, sono stati studiati i parametri chimico-fisici, nutrizionali e sensoriali. L'acidità libera è risultata essere simile durante la maturazione mentre indice di perossido, K232 e K270 sono diminuiti. Il contenuto totale di fenoli e la stabilità ossidativa hanno mostrato una tendenza simile. Prima sono aumentate e poi diminuite. α-tocoferolo, acidi grassi saturi e asprezza sono diminuiti. Il contenuto di polinsaturi è aumentato mentre il rapporto MUFAS/PUFAS è diminuito. Nel 2010, la maturazione del raccolto è stata più veloce e gli indici di maturazione delle colture sono stati più alti che nel 2009 nella stessa data di raccolta. Nello stesso frutteto, la maturazione sta cambiando ad ogni stagione di raccolto. Per questo motivo, è necessario scegliere la data ottimale di raccolta ; This work was made possible by a predoctoral fellowship awarded to María Abenoza and Marta Benito and the PI 170/09 project sponsored by the Aragon government. ; Peer reviewed

4 Pags., 2 Figs., 1 Tabl. Available online at www.inia.es/sjar ; [EN] The shortening of harvest time attained in hedgerow olive (Olea europaea L.) orchards represents an advantage for the adoption of this cropping system in areas that are prone to suffer frost during the harvest period. To establish an optimal harvesting window, we carried out a study of the fruit ripening process on a hedgerow orchard of 'Arbequina' olive trees, located in Zaragoza (Spain). From 2007 to 2009, oil accumulation on the fruit (% of dry weight) and oil yield (grams of oil per 100 fruits) were monitored, from early September to late November. Over the three years both variables peaked around November 15th, indicating that Arbequina reached full ripening earlier than has been reported previously for this variety. In two of the three seasons the orchard suffered several frosts during November. Long term climatic data from this area indicated that the risk of early frosts (<–2°C) increases as November progresses with a high risk after November 20th. In conclusion, the optimal harvesting period for Arbequina in this area should not extend beyond November 20th. A rapid harvesting before this date is advisable to avoid the risk of damage caused by early frost in Zaragoza. Hedgerow planting provides an additional advantage in frost-prone areas, because mechanization of operations permits a short harvest period, easier to fit into the optimal harvesting window. ; [ES] El acortamiento del periodo de recolección que permiten las plantaciones de olivar (Olea europaea L.) en seto re-presenta una ventaja para adoptar este sistema de plantación en áreas con heladas precoces durante el periodo de co-secha. Para establecer una ventana óptima de cosecha, llevamos a cabo un estudio de la maduración del fruto en una plantación en seto de 'Arbequina', localizada en Zaragoza (Aragón). De 2007 a 2009 se analizó la evolución del con-tenido en aceite en el fruto y la producción total de aceite, de primeros de septiembre a fnales de noviembre. En los tres años ambos parámetros mostraron los valores máximos hacia el 15 de noviembre, indicando que Arbequina alcan-za la madurez fsiológica antes de lo reportado hasta el momento. En dos de las tres campañas la plantación se vio afectada por fuertes heladas en noviembre. Datos climatológicos de la zona indican que el riesgo de heladas (< –2°C) aumenta según avanza noviembre, con un riesgo alto a partir del 20 de noviembre. En conclusión, el periodo apropia-do de cosecha de Arbequina en esta zona no debería extenderse más allá del 20 de noviembre; una rápida recolección anterior a esa fecha limitará el riego de daños por heladas. El sistema de plantación en seto es el que mejor permite acortar la recolección. Y representará una ventaja añadida en zonas con heladas tempranas, al permitir ajustar más fácilmente el periodo de recolección a la ventana óptima de cosecha. ; This work was supported partly by the project PI-170/09 (Aragón Government). ; Peer reviewed

10 Pags., 5 Tabls., 3 Figs. ; Phenolic compounds have a high importance in olive oil because of their effect on shelf life and sensory properties. This study reports on the HPLC profiles of the phenolic compounds of virgin olive oils obtained from Arbequina olives from the harvesting in a super-intensive orchard under a linear irrigation system. In addition, phenolic content, carotenoid and chlorophyllic pigments, and oxidative stability were analyzed. Total phenol content and 3,4-DHPEA-EDA increased up to a maximum throughout the ripening process. The simple phenols tyrosol and hydroxytyrosol acetate increased throughout the ripening process, however, there was not found a clear trend in hydroxytyrosol content. Minor constituents such as vanillic acid and p-coumaric acid increased up to a maximum and then decreased, since vanillin decreased progressively throughout the time of harvest. 3,4-DHPEA-EDA and lignans were present in considerable amounts in the studied samples, while oleuropein aglycone was present in a low amount. Total phenol content and oil stability followed the same trend throughout the study, so a very good correlation was established between them. Total secoiridoids and, specifically, 3,4-DHPEA-EDA seemed to be responsible for oil stability. The pigment content decreased during ripening, and not a positive correlation was found between pigments and oil stability. ; This work was made possible by a predoctoral fellowship awarded to Marta Benito and the PI 170/09 project given by the Aragon government. ; Peer reviewed

41 Pags., 10 Tabls., 5 Figs. The definitive version is available at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-0010 ; Background The aim of this work was to evaluate the evolution of the quality of extra virgin olive oil obtained from a super-high-density Arbequina orchard, under a drip irrigation system, throughout the ripening process. For this objective, physicochemical, nutritional and sensory parameters were studied. In addition, the oxidative stability, pigment content and colour evolution of olive oil were analysed during the ripening process. Results Free acidity increased slightly throughout the ripening process, while peroxide value and extinction coefficient decreased. Total phenol content and oxidative stability showed a similar trend, increasing at the beginning of ripening up to a maximum and thereafter decreasing. α-Tocopherol and pigment contents decreased with ripening, leading to changes in colour coordinates. Sensory parameters were correlated with total phenol content, following a similar trend throughout the maturation process. Conclusion By sampling and monitoring the ripeness index weekly, it would be possible to determine an optimal harvesting time for olives according to the industrial yield and the physicochemical, nutritional and sensory properties of the olive oil. ; This work was made possible by a predoctoral fellowship awarded to Marta Benito and the PI 170/09 project given by the Aragon government. ; Peer reviewed