| ABSTRACT |
As Malaysia is the second largest palm oil producer around the world, the Malaysian palm-based industry has been advancing rapidly and is producing an increasing number of products like fatty acid methyl esters, fatty alcohols and glycerin. Palm oil contains of two categories of minor components. The first one is made up of derivatives of fatty acid, mono-glycerides, di-glycerides, tri-glycerides, phosphatides, esters, and sterols. The second is non-fatty acid compounds, particularly hydrocarbons, and these include aliphatic alcohols, tocopherols, free sterols and pigments. Palm oil is high in saturated fatty acids. It contains 45% palmitic acid and 5% stearic acid. Three techniques are being used in Malaysia for the extraction process: screw press, solvent extraction, and pre-pressing followed by solvent extraction. Supercritical fluid extraction has become an important extraction technique in many fields, with the supercritical extraction technique; it is possible to extract sensitive compounds such as fatty acids and avoiding the residual toxic solvent as hexane. The most commonly solvent used in supercritical fluid is carbon dioxide; carbon dioxide has the additional advantage of being cost-effective, non-toxic, non-flammable, easily removed from the extract following decompression and due to its low critical temperature (31.1oC), it may be ideal technique to study the thermally labile compounds. Supercritical carbon dioxide is a good solvent for non-polar compounds extraction such as hydrocarbons. Usually, addition of a small amount of a liquid co-solvents (modi@257;er) and additives can enhance signi@257;cantly the extraction ef@257;ciency and, consequently, reduce the extraction time.
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