Fractionation procedures for obtaining cocoa butter-like fat from enzymatically interesterified palm olein

Solvent-free lipase-catalyzed incorporation of stearic acid in palm olein by the 1,3-regiospecific Novo Lipase Lipozyme IM20 resulted in the formation of a complex mixture of fatty acid glycerides and free fatty acids. The stearoyl incorporation in palm olein gave rise to the formation of 39.3% of the desired cocoa butter-like triglycerides in the fatty acid glyceride portion, namely distearoyl-oleoyl-glycerol (SOS), palmitoyl-oleoyl-stearoyl-glycerol (POS) and dipalmitoyl-oleoyl-glycerol (POP). A combination of fractionation steps involving initially the removal of free fatty acids (FFA) from the product mixture by steam distillation under vacuum, followed by fractional crystallization of the fatty acid-free glycerides in hexane and/or acetone, gave a fat, whose triglyceride composition and melting profile were comparable to that of cocoa butter as adduced by reversed-phase high performance liquid chromatography (HPLC) and differential scanning calorimetry (DSC). The yield of the cocoa butter-like fat was approximately 25% of the weight of the original palm olein.