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

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 (EOs) 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 EOs 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). Although 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 EOs. Thus, evaluating these combinations in other food matrices is important. PRACTICAL APPLICATION: Food oxidation is one of the main causes of food spoilage, and the search for natural antioxidants has become a necessity for society's increasing food knowledge and consumption preference. The research is focused on demonstrating that not only natural phenolic compounds with a "chain-breaking" mechanism have efficient antioxidant activity but also non-phenolic terpenes using the "termination enhancer" mechanism are efficient, but also the combination of them, which provides more alternative antioxidants for industrial applications.