The effect of solvent type and temperature on mono-diacylglycerol purification

Abstract

Mono-diacyl glycerol (M-DAG) resulted from esterification reaction between palm fatty acid distillates (PFAD) and glycerol with catalyst of methyl ester sulfonic acid, has low purity caused by the remaining catalyst, free fatty acids, free glycerol and triacylglycerol. Purification can be carried out by saponification and crystallization. The purpose of this study was to determine the most suitable solvent (96% ethanol, 70% ethanol, 95% isopropyl alcohol), and followed by determination of temperature level (2 °C, 5 °C, 10 °C) in crystallization step to obtain pure and high yield of M-DAG. Analyses that were carried out included yield, visual appearance, free fatty acid (FFA) content, and emulsion stability. The results showed that the type of solvent had an effect on the yield and free fatty acids, but did not affect the emulsion stability. Temperature also affected the yield and free fatty acids content, but did not affect the emulsion stability. The most suitable solvent was 96% ethanol with a yield of 24.2%, FFA content of 29.6%, and emulsion stability of 49.5%. The best temperature for crystallization was at 2 °C with a yield of 16.23%, FFA content of 3.80%, and emulsion stability of 100%.