Rapid quantification of the phenolic fraction of Spanish virgin olive oils by capillary electrophoresis with UV detection.

A rapid and reliable capillary zone electrophoresis method was used as a tool to obtain both qualitative and quantitative information about simple phenols, lignans, complex phenols (isomeric forms of secoiridoids), phenolic acids, and flavonoids in the solid-phase separation extracts from different Spanish extra-virgin olive oil in a short time (less than 6 min). Peak identification was done by using commercial and HPLC-isolated standards, studying the information of the electropherograms obtained at several wavelengths and also using the information previously reported. For the quantification of lignans and complex phenols (secoiridoid derivatives), we used a reference compound (oleuropein glucoside) at two different wavelengths (200 and 240 nm) and for the quantification of tyrosol and flavonoids, we used their commercially available standards.