Oxidative stability of ternary blends of vegetable oils: A chemometric approach

Abstract

Unsaturated fatty acids in vegetable oil are prone to lipid oxidation that leads to rancidity, subsequently, the oil's nutritional value is compromised. Edible oils can be tailored to obtain an antioxidant-rich oil blend with better oxidative stability under accelerated storage conditions. In this research, the oxidative stability of the six oil blends containing rice bran oil (RBO: 50–75%), flaxseed oil (FO: 5–10%), peanut oil (PO: 20–40%) at different concentrations is assayed by Arrhenius and Eyring equations (R2 > 0.95, p < 0.05) under Rancimat test conditions (100, 110, 120, 130 °C @ air flowrate 20L/h). The activation energy (Ea), enthalpy change (ΔH), and entropy change (ΔS) of control and oil blends ranged from 74.28 to 93.59 kJ/mol-K, 71.05–90.36 kJ/mol, −41.87 to −100.19 J/mol-K, respectively. Addition of RBO increased tocopherol and oryzanol content in oil blends from 398 to 725 ppm, 0.7 to 1.0 %g, respectively. Hierarchical cluster analysis conferred that RBO-PO-FO: 75-20-5, had better oxidative stability (induction period, IP100: 21.34 h) comparable to RBO with a slower kinetic rate and can be used as a functional oil source. Better understanding of the influence of oil blending on quality traits was delineated by principal component analysis.