1.- To evaluate the effects of pH on glutathione and sulfite loss during wine oxidation. 2.- To study the effects of wine pH on the formation and stability of selected lowmolecular weighty anthocyanin-derived pigments. 3.- Evaluate the effects of pH and trace metal ions content on the wine's antioxidant capacity and the presence of ethyl radicals. 4.- Assess the feasibility of using cation exchange resins treatments for sulfite reduction and improved oxidative stability in wines. 5.- To survey and correlate the chemical composition and antioxidant capacity of wines from different grape growing areas of the country. 6.- Evaluate the effects of production-scale cation exchange treatments on: 6.1.- The chemical composition of the treated wines. 6.2.- The oxidative stability and sensorial quality of the treated wines.