ANTIOXIDANT ACTIVITY OF AN ULTRAFILTRATION PERMEATE FROM ACID WHEY

Acid whey inhibited up to 90% of iron-catalyzed oxidation of phosphatidylcholine liposomes. Ultrafiltration, dialysis, heat treatment and chloroform extraction indicated that the primary antioxidant(s) in acid whey were polar, heat-stable compound(s) with molecular weights between 500 and 5,000. Lipid oxidation catalysts, including iron, lipoxidase, photoactivated riboflavin and hydrogen peroxide-activated metMb, were inhibited by acid whey and its ultrafiltration permeate. The antioxidant activity of the UF permeate increased with increasing pH (5.4-7.0). These data suggest that acid whey and its UF permeate could be used as a "natural" antioxidant.