CORRELATION OF REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY AND GAS-LIQUID-CHROMATOGRAPHY FOR FATTY-ACID COMPOSITIONS OF SOME VEGETABLE-OILS

The triacylglycerol compositions of six genetically modified soybean oils, and commercial soybean, com, safflower and sunflower oils were determined by reversed-phase high-performance liquid chromatography with flame ionization detection. Triacylglycerol molecular species were identified based on theoretical carbon numbers. Fatty acid compositions of the above soybean oils were estimated from concentrations of the triacylglycerol molecular species. Fatty acid composition was calculated by multiplying the concentration of each triacylglycerol by the percent of each fatty acid species in the triacylglycerol molecule. The fatty acid composition calculated from triacylglycerol analysis was compared with the composition determined by gas-liquid chromatography. There was good agreement between the fatty acid composition as calculated from the high-performance liquid chromatographic data and as determined by gas-liquid chromatography. These results support the findings that triacylglycerol molecular species could be identified based on theoretical carbon numbers and that fatty acid composition of soybean oil can be obtained from the data of reversed-phase high-performance liquid chromatography with flame ionization detection. The triacylglycerol composition for soybean oil obtained by this procedure required no response factors for quantitation.