Virgin olive oil quality of hedgerow 'Arbequina' olive trees under deficit irrigation

9 páginas.-- 6 tablas.-- 34 referencias.-- JM García et al.BACKGROUND: Regulated deficit irrigation (RDI) is used in hedgerow olive orchards to achieve a sustainable balance between water savings, tree vigor and oil production. Its effects on the presence of compounds responsible for the taste of the oil and its nutritional value are controversial. The present 3-year study was conducted in an ‘Arbequina’ orchard (1667 trees ha−1) under a full irrigation (FI) treatment (470.1 mm year−1 of water) and two RDI treatments scaled to replace 60% and 30%, respectively, of FI. The quality parameters, antioxidant contents and volatiles of the extracted virgin olive oil (VOO) were analyzed. RESULTS: In general, oils from the 30% RDI treatment had higher contents of pigments and phenolic compounds, a higher oleic/linoleic ratio and the highest oxidative stability, despite theirlower tocopherol content. FI oils showed higher (E)-2-hexenal, 1-penten-3-one, ocimene, E-2-pentenal and pentene dimer contents than 30RDI oils, but lower contents of (E)-2-pentenol and volatile esters. CONCLUSION: The results of the present study suggest that a RDI strategy supplying 30% of the total irrigation needs induces an increase in natural antioxidants in VOO. Neither yield, nor the rest of the quality parameters were affected by the reduced irrigation. However, abundant autumn precipitation can over-ride these effects of 30% RDI treatment on oil quality. © 2016 Society of Chemical IndustryThis work was funded by the Spanish Ministry of Science and Innovation (research project AGL2009-11310/AGR), by the Junta de Andalucía (research project AGR-6456-2010) and by the FEDER programme. The authors wish to thank Internacional Olivarera, SAU (Interoliva), for allowing us to carry out the experiments in the orchard. We also thank Carmen Martínez, Silvia Seller and Juan-Francisco Bernabé for their technical assistance.Peer reviewe