| Abstract
| - A red wine, made from Cabernet Sauvignon (60%) and Tannat (40%) cultivars, was fractionated byhigh speed countercurrent chromatography (HSCCC). The biphasic solvent system consisting of tert-butyl methyl ether/n-butanol/acetonitrile/water (2/2/1/5, acidified with 0.1% trifluoroacetic acid) waschosen for its demonstrated efficiency in separating anthocyanins. The different native and derivedanthocyanins were identified on the basis of their UV−visible spectra, their elution time on reversed-phase high-performance liquid chromatography (HPLC), and their mass spectra, before and afterthiolysis. The HSCCC method allowed the separation of different families of anthocyanin-derivedpigments that were eluted in different fractions according to their structures. The hydrosoluble fractionwas almost devoid of native anthocyanins. Further characterization (glucose quantification, UV−visible absorbance measurements) indicated that it contained flavanol and anthocyanin copolymersin which parts of the anthocyanin units were in colorless forms. Pigments in the hydrosoluble fractionshowed increased resistance to sulfite bleaching and to the nucleophilic attack of water. Keywords: Wine; HSCCC; anthocyanins; flavanols; adducts; LC/DAD/ESI-MS; derived pigments
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