NUCLEAR-MAGNETIC-RESONANCE AND GAS-CHROMATOGRAPHY MASS-SPECTROSCOPY ANALYSIS OF THE NONVOLATILE COMPONENTS PRODUCED DURING HEATING OF OLEIC-ACID ESTERIFIED PROPOXYLATED GLYCEROL, A FAT SUBSTITUTE MODEL-COMPOUND, AND TRIOLEYLGLYCEROL

Oleic acid esterified propoxylated glycerol (EPG-08 oleate) and triole ylglycerol were heated separately (192 +/- 8 degrees C for 12 h/day) u ntil the polymer content was greater than or equal to 20% and examined . Supercritical fluid fractionation (SFF) produced a monomer fraction of 98.3% purity and a dimer fraction of 90.8% purity for heated EPG-08 oleate and comparable fractions for triolein. Carbon-13 NMR analysis of the fractionated dimer (SFF-D) oil samples indicated peaks at appro ximately 107-108, 67-68, and 23.8 ppm that were present in only the SF F-D samples. The presence of these peaks in both samples indicated tha t the presence of the oxypropylene backbone was not necessary for the formation of the bonds corresponding to these peaks. The oxypropylene backbone profile was the same for the day 0 and the SFF-D sample. Gas chromatography/mass spectrometry of dimeric fatty acid methyl esters i ndicated that the fatty acid portion of the molecule was involved in d imer formation for both oil samples.