Solid-phase extraction and high-performance liquid chromatographic separation of pigments of red wines

The adsorption and desorption capacities of 11 different solid-phase extrac tion sorbents were tested for the preconcentration of pigments of various H ungarian red wines. The concentrates were evaluated by multiwavelengh spect rophotometry combined with a spectral mapping technique (SPM) and by revers ed-phase high-performance liquid chromatography. The highest (10-fold) conc entration of pigments was achieved on octadecylsilica sorbent. It can be us ed five times without losing adsorption and desorption characteristics. SPM indicated that multiwavelength spectrophotometry can be employed for the d ifferentiation of red wines. Comparison of the chromatograms of pigments wi th and without preconcentration showed that preconcentration makes possible the separation and detection of pigments present in low concentration in r ed wines. (C) 2000 Elsevier Science B.V. All rights reserved.