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

• Published in: Journal of thermal analysis and calorimetry 2019-02, Vol.135 (4), p.2389-2398
• Main Authors: Ghosh, Mousumi, Upadhyay, Rohit, Mahato, Dipendra Kumar, Mishra, Hari Niwas
• Format: Article
• Language: English
• Subjects: Activation energy; Air flow; Analysis; Analytical Chemistry; Antioxidants; Antioxidants (Nutrients); Calorimetry; Chemistry; Chemistry and Materials Science; Composition; Enthalpy; Entropy of activation; Fatty acids; Inorganic Chemistry; Lignans; Lipids; Measurement Science and Instrumentation; Mixtures; Omega 6 fatty acids; Oxidation; Oxidation-reduction reactions; Physical Chemistry; Polymer Sciences; Reaction kinetics; Retirement benefits; Sesame oil; Stability analysis; Temperature dependence; Thermal stability; Thermogravimetry; Tocopherols
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-018-7342-4

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