Study of the Oxidative Stability of Chia Oil (Salvia hispanica L.) at Various Concentrations of Alpha Tocopherol

Cold-pressed chia oil (Salvia hispanica L.) is highly susceptible to oxidative deterioration due to its exceptional α-linolenic acid content. This study evaluated the effect of increasing α-tocopherol concentrations (0–0.10% w/w) on its oxidative stability through accelerated oxidation testing (Oxitest) and long-term refrigerated storage. α-Tocopherol was selected because it is a widely accepted antioxidant in edible oils according to the Codex Alimentarius and FAO/WHO guidelines. A randomized block design (n = 3 independent extraction batches) was used to determine the induction period (IP) at 80 °C, followed by a 15-month evaluation at 15 °C of the control and the most promising treatment. α-Tocopherol increased oxidative resistance in a dose-dependent manner, but concentrations above 0.05% offered no additional benefits. The 0.05% treatment significantly prolonged the IP and effectively limited increases in peroxide and acidity values, keeping all parameters within Ecuadorian regulatory limits and consistent with international quality standards. Fatty-acid profiling confirmed that this antioxidant level slowed α-linolenic acid degradation, preserving the PUFA-rich profile of chia oil. These findings show that low-level α-tocopherol supplementation is a practical strategy to improve long-term stability of cold-pressed chia oil without altering its nutritional properties, providing valuable evidence for the formulation and commercialization of premium functional oils.