Antioxidants in margarine emulsions

Abstract

The lipid oxidation in margarine takes place in continuous liquid oil phase. The extension of fat interfaces in the system - emulsion of water in oil and the dispersion of fat crystals in liquid oil influences on the peroxidation, decomposition of hydroperoxides to aldehydes and the oxidative stability in the comparison with oxidation in the fat blend. Different antioxidants were used in margarine dispersions: L(+)ascorbic acid, ascorbyl palmitate and DL-α-tocopherol. Increasing polarity and decreasing molecular size of antioxidants have the positive influence on lipid oxidation: DL-α-tocopherol is the least effective antioxidant of all antioxidants, ascorbic acid is the most effective antioxidant and ascorbyl palmitate possesses similar, however, lesser effect. The combination of all three antioxidants restricts the production of hydroperoxides, the decomposition of hydroperoxides to aldehydes and the increase of oxidative stability was also achieved. Content of antioxidants 0.02% as ascorbic acid or ascorbyl palmitate mostly restrict the extent of lipid oxidation in the margarine dispersion with existent content of naturally present tocopherols in fat blend.