All results show that the white sediment is composed of methyl ester, mono-, diglyceride and glycerinabout 49 %wt. Others may be unsaponifiable substances such as aliphatic alcohols, sterols, pigments and hydrocarbons. These substances frequently dissolve in fatty acids, which cannot be saponified by caustic treatment, but they are soluble in the normal fat solvents. These unsaponifiable matters affect high cloud point and pour point of biodiesel and it can aggregate for clog in engine system (e.g. fuel injector nozzle and fuel filter), which decrease flow ability in engine at low temperature [8].