Direct determination of phenolic compounds in Sicilian wines by liquid chromatography with PDA and MS detection

Phenolic compounds in Sicilian wines were directly detected using an HPLC with a PDA detector coupled on-line with a MS system equipped with Electrospray Ionisation (ESI) source operated in the negative-ion mode and a quadrupole mass analyzer. In this work, NIS spectra were recorded at different voltage, to obtain structural elucidations in addition to molecular mass informations. The different response of the compounds identified has been also evaluated. NIS characteristics of cis- and trans-piceid were determined on the basis of the response obtained with the ESI interface. The method allowed both the identification and determination of 24 phenolic compounds in 22 different commercial Sicilian red wines by direct injection, without any prior purification of the sample. The data on the levels of all the phenolic compounds in the red Sicilian commercial wines showed that the wine samples from Merlot grapes generally had the highest phenolic compounds content.