Impact of α-tocopherol and EGCG on the oxidative stability of margarine: Exploring the possible synergistic effect mechanism.

Margarine is a typical water-in-oil (W/O) emulsion fat product. Due to the presence of a water-oil interface, the oil oxidation in the emulsion system is the interface reaction, which is much faster than that in bulk oil and shows different oxidation mechanisms. The analysis of Rancimat and electron spin resonance indicated that α-tocopherol and EGCG show synergistic antioxidant effects in the margarine. After 20 days of accelerated oxidation storage, the antioxidant effect of the compound antioxidant (50 mg/kg α-tocopherol + 350 mg/kg EGCG) on the margarine was significantly higher than that of the single antioxidant α-tocopherol and EGCG. Based on the results of antioxidants partitioning, electrochemistry, fluorescence spectroscopy, and the oxidative decomposition of antioxidants, the possible mechanisms of interaction were the promotion of α-tocopherol regeneration by EGCG, and the fact that α-tocopherol and EGCG could act at different stages and positions of oxidation. This work will contribute to studying antioxidant interactions and can provide valuable suggestions for practical production. PRACTICAL APPLICATION: This study aims to improve the oxidative stability of margarine by adding α-tocopherol and epigallocatechin-gallate (EGCG) individually and in blends. The mechanism of compound antioxidant synergistic inhibition of margarine oxidation was analyzed, providing theoretical basis and scientific basis for the research and practical application of natural antioxidant synergistic mechanism.