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The characterisation of virgin olive oil from Arbequina, Carrasqueña, Corniche, Manzanilla Cacereña, Morisca, Picual, and Verdial de Badajoz varieties according to the individual phenolic compounds at different ripening stage was carried out. In all olive oil varieties studied, secoiridoid derivatives were most abundant, followed by phenolic alcohols, flavonoids and phenolic acids. The secoiridoid derivatives of hydroxytyrosol were the most important complex phenols for Picual and Carrasqueña, whereas the tyrosol derivatives were the major ones found in Manzanilla Cacereña, and Verdial de Badajoz. For secoiridoid derivatives of hydroxytyrosol and tyrosol, Arbequina was the oil variety showing the lowest concentration. Tyrosol, hydroxytyrosol, vanillic acid, p-cumaric acid, luteolin, and apigenin levels were greater in early harvested samples in almost all oils analysed. Antioxidant activity measurements (antiradical, lipid peroxide inhibition, H2O2 and NO scavenging) were also accomplished for the seven varieties in the first ripening stage., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The aim of this research was to evaluate strategies for the development of a virgin olive oil (VOO) enriched with aqueous extracts of olive leaf and cake to increase the necessary dose in the diet of phenolic compounds with a natural product, as phenolic compounds are involved on the healthy properties of olive oil. Different extraction procedures were evaluated with the aim of increasing the phenol content and antioxidant potential of extracts of olive leaf and cake. As leaves extract presented a higher total phenolic content, it was characterized in order to determine its phenolic profile, and was employed to enrich VOO. Diverse procedures were used to prepare enriched VOO with the leaves extract, and finally the effects of phenol enrichment were evaluated based on the antioxidant potential and oxidative stability of the prepared phenol-enriched virgin olive oils. These enriched VOOs increased significantly the content in phenolic compounds, antioxidant potential and oxidative stability 40, 4 and 1.5 fold more, respectively, than the Control oil. Furthermore, the addition of lecithin had a positive effect both on the phenolic compounds content, and on the antioxidant potential of the oils. Besides, the use of the olive leaves extract, with and without lecithin respectively, supposes a strategy potential for reducing the harmful effects that inflicts long-term preservation of VOOs and its possible deterioration.