Crystallisation and Melting Behavior of Methyl Esters of Palm Oil

Abstract

The methyl esters of palm oil, which consists of saturated and unsaturated esters (0.6 to 95.9% unsaturation) of the C12 to C18 fatty acids, solidify at the two temperature ranges, -52 to -45°C and -24 to 21°C, when the esters are cooled. When the esters are heated, they melt at two distinct temperatures, -25 and -33°C and a broad peak at -9 to 28°C. The heating thermograms also showed an exothermic crystallisation peak in between two endothermic melting peaks, indicating the occurrence of re-crystallisation of low melting methyl esters into higher melting point crystal and then melt again at higher temperature.