Fast separation and determination of phenolic compounds by capillary electrophoresis–diode array detection: Application to the characterisation of alperujo after ultrasound-assisted extraction

A dynamic approach has been proposed for the ultrasound-assisted extraction of twenty phenolic compounds from alperujo, a semisolid waste from the olive oil industry, that is a representative example of samples with a complex matrix. Multivariate methodology was used to carry out a detailed optimisation study of both the separation–determination and extraction steps in terms of resolution-analysis time and extraction efficiency, respectively. Consequently, the proposed method was able to extract the target analytes in 13 min; then, after dilution and centrifugation, the extract was injected into the capillary electrophoresis–diode array detection system for individual separation determination in 11 min. No cleanup of the extract was required. This method is less time-consuming, more selective and provides a larger information level than the Folin–Ciocalteau spectrophotometric method. Alperujo was demonstrated to be a powerful source of phenolic compounds, particularly as compared with olive oil—8680 versus 50–1200 μg/g.