Oxidation protection efficiency of the combination of Minthostachys mollis K. and Origanum vulgare L. essential oils with “chain‐breaking” and “termination‐enhancing” antioxidant mechanisms

Abstract

The use of antioxidants is known to reduce lipid oxidation. This study aimed to assess the interaction of two antioxidant mechanisms, namely "chain-breaking" and "termination-enhancing" by combining natural antioxidants derived from “oregano” (Origanum vulgare L.) and “peperina” (Minthostachys mollis K.) essential oils in an accelerated oxidation process of sunflower oil at 60 °C. Concentrations of 0.05% w/w (1) and 0.02% w/w (2) of the combined oregano and peperina essential oils were evaluated. Chemical and volatile oxidation markers were determined in comparison with the pure compounds, an antioxidant-free control, and a BHT-treated sample (0.02% w/w). While the combinations exhibited lower oxidation indicator values (Anisidine ≈ 136) compared to the control (Anisidine ≈ 213), no evidence of a synergistic effect was observed (Anisidine: Oregano 1 ≈ 52; Oregano 2 ≈ 199; Peperina 1 ≈ 155; Peperina 2 ≈ 153), indicating that the combination did not enhance their antioxidant activity beyond that of the pure essential oils. Thus, evaluating these combinations in other food matrices is important.