Hydrodynamic, thermo-analytical and molecular structural investigations of enzyme interesterified oil and its thermo-oxidative stability by thermogravimetric analysis

Abstract

This paper deals with the effect of lipase-catalyzed interesterification of oil on hydrodynamic, thermo-analytical, structural properties and its stability. Interesterification of rice bran oil (RBO) and refined, bleached, deodorized palm olein (RBDPO) blend in 1:1 ratio was carried out at 60 ± 1 °C under stirring for 6 h. Results showed that hydrodynamic property of oils decreased from 3.61 × 10⁻⁶ in RBDPO to 2.91 × 10⁻⁶ m² s⁻¹ in enzyme interesterified oil (EI) and heat transfer coefficient increased from 221.0 in RBDPO to 250.7 Wm⁻² °C⁻¹ in EI over 170–190 °C. Peak melting point of triacylglycerols shifted from 10.36 °C in RBDPO to −4.76 °C in EI. Trisaturated triacylglycerols decreased from 4% in RBDPO to 0.6% in EI. The first step of thermal decomposition started at 190, 212.7 and 238.9 °C for RBDPO, RBO and EI, respectively. Sensory evaluation of poori fried using these oils revealed no significant (p > 0.05) differences in sensory attributes of the fried product.