Analysis of grape and wine anthocyanins by HPLC-MS.

The development and application of valuable analytical tools suitable for the varietal authentication of premium red wines are matters of interest in order to avoid fraud. In this study, an HPLC-MS procedure has been developed using trifluoroacetic acid as an acid modifier in the mobile phase. This method may be used as a routine method using UV-vis detection and allows the simultaneous analysis of the structural features of anthocyanins by MS under the same chromatographic conditions. Twenty different anthocyanins have been detected in 19 different samples of both grape extracts and wines. Cis and trans isomers of p-coumaryl derivatives have been identified for the first time. Important qualitative and quantitative differences among cultivars have been detected.