Preparation of hard palm midfractions (PMF) and its use as a cocoa butter equivalent ingredient were studied. Hard PMF is obtained by multistep fractionation of palm oil involving dry fractionation (DF) and/or solvent fractionation (SF), usually using hexane or acetone. From our experience, in acetone, a polar solvent, symmetrical 1,3-disaturated triacylglycerols tend to selectively crystallize more than nonsymmetrical 1,2-or 2,3-disaturated triacylglycerols, making it suitable for obtaining the solid midfraction. Unfortunately, triacylglycerols are very soluble in hexane, and temperatures at least 15 degrees lower than those required for acetone must be used for equivalent crystal yields. On the other hand, DF is a less expensive and safer process. Thus, multistep fractionation combining DF and SF using acetone was developed to achieve sufficient removal of high-melting components, and further enrichment of 1,3-dipalmitoyl-2-oleoylglycerol and the hard PMF was obtained by triple-step fractionation of palm olein or double-step fractionation of soft PMF. Compared to conventional hard PMF, this hard PMF had a steeper melting curve and better snapping and sharp-melting qualities when used in chocolate. Heat resistance of the hard PMF chocolate was similar to the conventional hard PMF chocolate, and its bloom resistance could be improved by adding polyglycerol fatty acid esters. Paper no. J9713 in JAOCS 78, 455-460 (May 2001). Hard palm midfractions (PMF) used as an ingredient of cocoa butter equivalents (CBE) are obtained by multistep fractionation of palm oil (1). Palm oil is abundant, inexpensive, and a good source of CBE. For example, palm oil [iodine value (IV) = 51-53] can be fractionated into palm stearin (IV = 32-40) and palm olein (PO; IV = 56-58), and the PO can then be fractionated into soft PMF (sPMF; IV = 44-50) and palm super-olein (IV = 63-65). A hard PMF (IV = 34-36) can finally be obtained by fractionation of the sPMF by separation from the PO fraction (IV = 64-70) (all IV values depend on fractionating conditions).Hard PMF is rich in 1,3-dipalmitoyl-2-oleoylglycerol (POP) and is characterized by its hardness at room temperature and sharp melting property at around 30-35°C, like cocoa butter. However, the content of a few percent of highermelting trisaturated triacylglycerols (SSS) and of diacylglycerols (DG) in hard PMF has an adverse effect on these properties, and is best removed completely to achieve more rapid and complete melting in the mouth. From our experience, acetone, a polar solvent, is suitable for obtaining the solid midfraction, because symmetrical 1,3-disaturated triacylglycerols (SUS) in acetone tend to selectively crystallize more than nonsymmetrical 1,2-or 2,3-disaturated triacylglycerols (SSU), while in nonpolar hexane, both symmetrical and nonsymmetrical disaturated triacylglycerols (S 2 U) tend to be nonselectively crystallized. Triacylglycerols are very soluble in hexane, but this means that temperatures at least 15°C lower than those required for acetone must be used for equiv...
