LAUSR

BACKGROUND In this study, the effects of crop year, harvest date and clone on the fruit characteristics and chemical composition of Empeltre olive oils were evaluated. For this purpose, the weight and oil content of fruit and the fatty acid composition, polyphenol content and oxidative stability of the olive oil was analysed throughout ripening during three successive seasons. RESULTS The weight and moisture in the fruit, as well as the fatty acids and polyphenol content in the olive oil were mainly affected by crop year. In contrast, the stability was strongly influenced by the harvest date. Both factors had an influence on the fruit's oil content. The clone was not a substantial component in terms of variability, although the interaction with crop year was notable for some of the characteristics. The oil content increased significantly along with the harvest date and reached maximum values in the last period (44.9%). Conversely, stability and polyphenols decreased significantly (depending on the year, by 30-70%) from October to December reaching the highest mean values between 1 October and 10 November (15.5 h; 500 mg caffeic acid/kg). Oleic acid and MUFA/PUFA did not show significant differences depending on the harvest date, but between years, with 2018 having the highest percentage of oleic acid (72.72%) and MUFA/PUFA (8.38). CONCLUSION Early harvesting of Empeltre olives would provide considerably more stable olive oils, regardless of the clone selected, with higher phenolic content. It would not affect the MUFA/PUFA ratio, mainly influenced by the crop year. This article is protected by copyright. All rights reserved.