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Antioxidative activity of native acid whey powder in Maillard reaction product and oil-in-water emulsion

J. SHON, Dept. of Food Science, Nutrition & Health Promotion, Mississippi State Univ., 110 Herzer Bldg., Mailstop 9805, Mississippi state, MS 39762-9805 and Z. Z. Haque, Dept. of Food Science, Nutrition and Health Promotion, Mississippi State Univ., 203 Herzer Bldg., Campus Mailstop 9805, Mississippi State, MS 39762-9805.

Lipid oxidation and browning of food products are major problems for the food industry. Acid whey is a by-product of cottage whey manufacture that presently has little food usage due to its high acid content. Novel usage of this nutritious resource would enhance dairy profitability and solve a disposal problem. The objectives of this study were to evaluate the effect of acid whey on Maillard reaction products (MRPs) and on oxidative stability of oil-in-water emulsions. The pH and color changes of acid whey solutions were determined after storage for up to 5 days at 40°C to monitor development of MRPs. The MRPs were catalyzed by iron redox using FeCl3, H2O2, and ascorbate. The ability of acid whey to inhibit lipid oxidation was also tested in a model system containing iron-catalyzed peanut oil emulsions (Tween 20 Stabilizer) after 96 hr storage at 40°C. Antioxidant activity was determined using a thiobarbituric acid-reactive substances (TBARS) and a modified ferric thiocyanate (FTC) method. Maillard browning decreased with increasing concentration of acid whey. Acid whey significantly reduced TBARS by 55% and peroxide value (PV) by 38% in iron-catalyzed peanut oil emulsions compared to control. Usage level of 20% (w/v) was the most effective and comparable to all chemical antioxidants used. Data show that acid whey was an effective in inhibiting iron, ascorbate, and hydroperoxide-catalyzed lipid oxidation as measured by TBARS and lipid peroxide. Results of this study suggested that acid whey, which is presently considered to be a waste product, could be used as natural antioxidant in foods.

Session 83, Food Chemistry: Antioxidant and bioactive agents
2:30 PM - 5:30 PM, Tuesday PM Room 393

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana