Thermal and oxidative stability assessment of synergistic blends of sunflower and sesame oils tailored for nutritionally stable composition of omega fatty acids

The thermal stability of ω-6 fatty acid-rich oils is a bewildering problem. The synergistic blends of sunflower (SO) (50–80%) and sesame oil (SEO) (20–50%) were optimized for improved thermal stability, better retention of antioxidants, and balanced ratio of ω-fatty acids (ω-6 and 9). The oil blends were thermally oxidized by Rancimat (temperature 100, 110, 120, and 130 °C; airflow rate 20 L h −1 ) for estimating the induction period (IP) and kinetic rate constant ( k ) of lipid oxidation. The oils were exhaustively characterized for thermal stability by thermogravimetry and differential scanning calorimetry. The temperature-dependent kinetics of lipid oxidation was described using Arrhenius equation (ln k vs. 1/ T ) and activated complex theory (ln k / T vs. 1/ T ). The calculated kinetic parameters, viz. activation energies, activation enthalpies, and entropies varied from 90.80 to 99.17, 87.58 to 95.94, − 33.28 to − 4.78 J mol −1 K −1 , respectively ( R 2 > 0.90, p