Wine is usually aged in oak barrels. In this study, young red wines were treated with ultra-high pressure (UIIP) to stimulate the ageing process. Changes in phenolic acids, flavan-3-ols and proanthocyanidins were determined by reverse-phase high pressure liquid chromatography (RP-HPLC).

The concentration of phenolic acids increased, while the levels of flavan-3-ols decreased. The content and structure of proanthocyanidins also changed and the tendency was similar to that of natural ageing.