Dual-electrode liquid chromatography-electrochemistry was used to detect flavanols and procyanidins in wine and grape seeds. Compounds were identified on the basis of their retention times and voltammetric behaviour. Epicatechin, catechin and epicatechin gallate were identified in the grape seed extract. The presence of epicatechin gallate was further verified through the use of the enzyme tannase. Flavanols and procyanidins were isolated from red wine using a solid-phase extraction procedure. Procyanidin B-2, epicatechin and catechin were all identified in the wine extract based on a combination of retention times and voltammetric behaviour.