ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Evaluation of the oxidation kinetics and stability of soybean oil supplemented with ethanolic extract of Nepeta (Nepeta binaludensis Jamzad) as compared to butylated hydroxytoluene

Afsaneh Azimi Mahalleh, Parvin Sharayei, Elham Azarpazhooh, and Hosahalli S. Ramaswamy

Islamic Azad University, Sabzevar, Iran

E-mail: parvin_sharayei@yahoo.com

Abstract: The oxidative stability and oxidation kinetics of pure soybean oil (PSO) supplemented with 0.5–6% of pulse electric field ethanolic extract (PEF_x) of Nepeta (Nepata binaludensis Jamzad) or 100 ppm of butylated hydroxytoluene (BHT) were evaluated at 100–120 °C. The oxidative stability of PSO decreased with increasing temperature and improved significantly (p < 0.05) by added PEF_x at the levels 0.5% and higher. The reaction rate constants increased linearly with increasing temperature from 100 to 120 °C. The temperature coefficients of PSO with added PEF_x at different concentrations ranged from − 3.37 × 10⁻² to − 4.79 × 10⁻² °C as compared with -2.79 × 10⁻² °C with BHT. The values of activation energies, temperature acceleration factors, activation enthalpies and entropies for oxidative stability of the PSO with added PEF_x at different concentrations ranged from 92 to 100 kJ/mol, from 2.13 to 2.27, from 88.8 to 96.9 J/mol K and − 71.9 to − 91.1 kJ/mol, respectively, as compared with 66.5 kJ/mol and − 162 kJ/mol with added BHT.

Keywords: Nepeta binaludensis ; Soybean oil ; Oxidation ; Kinetics ; Phenolic compound ; Antioxidant 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-019-00772-3

Chemical Papers 73 (9) 2231–2239 (2019)