Changes in triacylglycerol molecular species and thermal properties of blended and interesterified mixtures of coconut oil or palm oil with rice bran oil or sesame oil

Abstract

Blended oils were prepared by mixing appropriate amounts of coconut oil (CNO) or palm oil (PO) with rice bran oil (RBO) or sesame oil (SESO) to get approximately equal proportions of saturated/monounsaturated/polyunsaturated fatty acids in the oil. These blended oils were subjected to interesterification reactions using lipase to randomize the fatty acid distribution on the glycerol molecule. The fatty acid compositions of the modified oils were evaluated by gas chromatography while changes in triacylglycerol molecular species were followed by HPLC. The triacylglycerol molecular species of the blended oils reflected those present in the parent oil. Interesterification of the blended oils resulted in the exchange of fatty acids within and between the triacylglycerol molecules, resulting in alterations in the existing triacylglycerol molecules. Emergence of new triacylglycerol molecular species following interesterification was also observed. The thermal profiles of the native, blended and interesterified oils were determined by differential scanning calorimetry. Thermal behaviour, melting and crystallization properties of the modified oils showed significant changes reflecting the changes in the triacylglycerol molecules present in the oil. Therefore, interesterification of oils introduces significant changes in the physical properties of oils, even though the overall fatty acid composition of blended and interesterified oils remains the same.

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

“…There was no significant change observed (p > 0.05) in fatty acid compositions of blended oils (saturated-35.5%, polyunsaturated-21.5%) and enzyme interesterified (saturated-35.6%, polyunsaturated-21.3%) counterparts (Table 2). Similar observations were reported earlier by us (Reena et al, 2009;Debnath et al, 2011).…”

“…The lipase-catalyzed interesterification (transesterification) reaction of RBO-RBDPO blend was carried out in a reciprocating shaking water bath (model BS-31, Jeio Tech Co. Ltd., South Korea) as described earlier (Reena et al, 2009). The binary oil blend (BL) was taken in a round-bottomed flask in the mass (w/w) ratio of 1:1, placed on a constant temperature (60 ± 1°C) water bath.…”

Ultrasound-assisted aqueous enzymatic extraction of oil from perilla (Perilla frutescensL.) seeds

“…The fatty acid methyl esters (FAMEs) were prepared by the following two steps: (1) oils were saponified with 0.5 M KOH; (2) later methylated with 40% BF 3 in methanol (Reena, Reddy, & Lokesh, 2009). Gas chromatography mass spectrometry (GC/ MS) analysis was carried out with an Agilent 6890-5973 (Agilent Technologies, CA, USA) instrument.…”

Enzymatic Synthesis of Structured Lipid Based on Silkworm Oil and Palm Olein

“…The molecular species were eluted with mobile phase acetone (100%) at a flow rate of 1 ml min -1 . The molecular species of oils and SL were tentatively identified by their equivalent carbon numbers (ECN) and with the elution order (Reena, 2009;Buchgraber, 2004).…”