Keywords: crude palm kernel oil; physicochemical characteristic; triacylglycerol profile; fatty acid composition; thermal behaviour

Abstract

This study was carried out to determine the physicochemical properties of Malaysian crude palm kernel oil (CPKO). The physicochemical properties showed that the free fatty acid (FFA%) of 3.7±0.1%, acid value of 10.4±0.1 mg/g, iodine value of 20.8±0.6 mg/g, hydroxyl value of 45.06±0.3 mg/g, refractive index at 28°C of g/ml, 1.455, moisture content of 0.5±0.1%, viscosity at 28°C of 40 cP, Lovibond colour (R/Y) at 28°C of 0.5R–20Y. The gas chromatography-flame ionisation detector was used to determine the fatty acid composition in CPKO. The results showed that the dominant fatty acids are lauric acid (44.5±0.7%), oleic acid (18.0±0.5%), myristic acid (16.9±0.1%) and palmitic acid (9.4±0.2%). The major triacylglycerols (TAGs) of CPKO estimated using high-performance liquid chromatography were LaLaLa (32.91%), LaLaM (23.59), LaOLa (9.93%) and CLaLa (9.10%). The differential scanning calorimetry showed that the crystallisation of CPKO displayed two major exothermic regions of CPKO with the saturated TAG at 6.11°C and the unsaturated TAG at -2.10°C. The melting curve of CPKO displayed two endothermic peak regions at 9.13°C and 24.08°C.