## 3 Results
### Effect of PEF Technology on the Phenolic and Tocopherol Composition of VOO
Thus, significant increases in the phenolic content of VOO have  
\begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline  & \multicolumn{2}{c}{**1 st Pilot Tests**} & \multicolumn{2}{c}{**2 nd Pilot Tests**} & \multicolumn{2}{c}{**3 rd Pilot Tests**} & \multicolumn{2}{c}{**Industrial Tests**} \\ \hline
**Phenols (mg kg\({}^{-1}\))** & **Control** & **PEF** & **Control** & **PEF** & **Control** & **PEF** & **Control** & **PEF** \\ \hline Hydroxyytrosol & \(1.3\pm 0.4\) & \(1.2\pm 0.2\) & \(0.0\pm 0.8\) & \(1.5\pm 0.3\) & \(0.6\pm 0.0\) & \(1.2\pm 0.8\) & \(2.0\pm 0.1\) & \(2.3\pm 0.2\) \\ Tyrosol & \(2.3\pm 0.1\) & \(2.1\pm 0.0\) & \(3.3\pm 0.2\) & \(3.1\pm 0.1\) & \(5.0\pm 0.4\) & \(5.0\pm 0.6\) & \(4.5\pm 0.1\) & \(4.7\pm 0.0\) \\ Vanillic acid & \(0.4\pm 0.1\) & \(0.3\pm 0.0\) & \(0.5\pm 0.1\) & \(0.4\pm 0.0\) & \(0.6\pm 0.1\) & \(0.7\pm 0.0\) & \(0.6\pm 0.0\) & \(0.6\pm 0.1\) \\ Vainillin & \(0.1\pm 0.0\) & \(0.2\pm 0.0\) & \(0.1\pm 0.0\) & \(0.1\pm 0.0\) & \(0.1\pm 0.1\) & \(0.1\pm 0.0\) & \(0.2\pm 0.0\) & \(0.2\pm 0.0\) \\ \(p\)-counter acid & \(1.3\pm 0.2\) & \(1.2\pm 0.3\) & \(0.9\pm 0.2\) & \(0.9\pm 0.1\) & \(0.7\pm 0.1\) & \(0.6\pm 0.3\) & \(0.8\pm 0.0\) & \(0.8\pm 0.0\) \\ Hy acetate & \(3.7\pm 0.2\) & \(6.2\pm 0.3\) & \({}^{*}\) & \(1.9\pm 0.0\) & \(2.0\pm 0.0\) & \(1.2\pm 0.2\) & \(6.1\pm 7.8\) & \(2.4\pm 0.2\) & \(2.4\pm 0.5\) \\ 3-4-DHPEA-EDA & \(126.3\pm 4.2\) & \(147.4\pm 7.4\) & \({}^{*}\) & \(59.0\pm 3.8\) & \(69.5\pm 4.5\) & \({}^{*}\) & \(9.1\pm 0.9\) & \(8.2\pm 3.4\) & \(66.6\pm 0.08\) & \(61.8\pm 0.1\) \\ \(p\)-HPEA-EDA & \(147.1\pm 2.9\) & \(164.6\pm 6.5\) & \({}^{*}\) & \(74.6\pm 3.2\) & \(75.8\pm 5.8\) & \(26.1\pm 1.8\) & \(21.9\pm 8.4\) & \(31.4\pm 1.5\) & \(26.5\pm 0.9\) \\ Pinoresinol & \(7.7\pm 0.2\) & \(7.4\pm 0.3\) & \(6.7\pm 0.2\) & \(9.1\pm 0.4\) & \(3.0\pm 0.1\) & \(2.5\pm 0.6\) & \(0.3\pm 0.0\) & \(0.2\pm 0.0\) \\ Cinanzic acid & \(0.6\pm 0.5\) & \(0.5\pm 0.4\) & \(3.4\pm 0.1\) & \(2.6\pm 0.1\) & \(0.3\pm 0.1\) & \(0.9\pm 0.4\) & \(0.9\pm 0.0\) & \(0.9\pm 0.0\) \\ Acetotypimes & \(107.0\pm 3.8\) & \(10.8\pm 2.8\) & \(25.4\pm 3.4\) & \(27.0\pm 2.9\) & \(15.7\pm 0.8\) & \(13.1\pm 2.9\) & \(23.6\pm 1.2\) & \(23.5\pm 2.0\) \\
3-4-DHPEA-EA & \(176.2\pm 3.9\) & \(172.5\pm 6.1\) & \(301.5\pm 13.0\) & \(337.0\pm 17.6\) & \({}^{*}\) & \(34.0\pm 2.6\) & \(30.0\pm 4.1\) & \(362.1\pm 9.1\) & \(395.2\pm 3.6\) \\ \(p\)-HPEA-EA & \(50.0\pm 0.8\) & \(49.5\pm 1.6\) & \(42.9\pm 1.1\) & \(41.5\pm 7.7\) & \(6.4\pm 0.3\) & \(6.3\pm 1.2\) & \(24.7\pm 1.6\) & \(22.2\pm 0.9\) \\ Ferulic acid & \(0.3\pm 0.0\) & \(0.3\pm 0.0\) & \(0.3\pm 0.1\) & \(0.3\pm 0.1\) & \(0.2\pm 0.0\) & \(0.2\pm 0.0\) & \(0.5\pm 0.0\) & \(0.5\pm 0.00\) \\ Luteolin & \(2.0\pm 0.2\) & \(1.8\pm 0.0\) & \(3.5\pm 0.6\) & \(3.10\pm 0.7\) & \(10.3\pm 1.1\) & \(10.1\pm 1.5\) & \(2.2\pm 0.0\) & \(2.3\pm 0.10.1\) \\ Apigenin & \(0.7\pm 0.2\) & \(0.6\pm 0.1\) & \(1.4\pm 0.5\) & \(1.1\pm 0.1\) & \(3.4\pm 0.6\) & \(3.3\pm 0.7\) & \(0.9\pm 0.0\) &been reported by applying PEF technology in cultivars 'Arroniz', 'Coratina', 'Carolea' and 'Ottokrata' [15; 28]. Very slight or no effect has been found for other olive cultivars such as 'Nocellara del Belice' [18]. In our study, the application of PEF technology not only affected the total phenolic content of VOO, but also the content of some individual phenolic components. Thus, statistically significant increases (\(p\leq 0.05\)) were found in the contents of oleacein, oleocanthal, 3,4-DHPEA-EA and hydroxytyrosol acetate. The contents of some of these phenolic compounds in the 'Manzanilla' oils extracted with PEF technology were in the range 10-17% higher than in control oils. In this sense, [PERSON] et al. [18] had already described similar results with the 'Nocellara del Belice' cultivar, finding significantly higher amounts of oleacein and oleocanthal compounds in the oils obtained with PEF technology, although without observing significant increases in the total phenolic content.