First Evidence of Acetaldehyde-Flavanol Condensation Products in Red Wine

Abstract

A dimeric polyphenolic fraction was purified from a two months old Cabernet Sauvignon wine. This fraction was studied by LC-ES-MS. Several products with a 606 mass corresponding to a dimer of 2 flavanol monomer units linked by an ethyl bridge were detected. Identification of catechin-acetaldehyde dimers was achieved by injection of synthetic dimers. In addition to retention time, mass spectra were obtained on each peak. By increasing the cone voltage in the electrospray source, specific fragments could be generated which further confirm the structures of the molecules.