TRIACYLGLYCEROL STRUCTURES OF FOOD FATS HIGH IN SATURATED ACIDS BY HPLC AND MASS SPECTROMETRY

Abstract

Triacylglycerol (TAG) compositions by area percent were obtained by reverse-phase high-performance liquid chromatography (RP-HPLC) coupled with atmospheric pressure chemical ionization mass spectrometry (APCI-MS) of highly saturated fatty acid fats, such as coconut, cocoa butter, palm, randomized palm, palm olein, and randomized palm olein oils. Accurate identification and quantitation of these TAG compositions were obtained and proved by comparison of the fatty acid composition calculated from the TAG composition obtained by APCI-MS with the fatty acid composition obtained by gas chromatography of the methyl esters of the transmethylated oils. Also, APCI-MS accuracy was proved by comparison of the experimental TAG composition with the predicted TAG composition for randomized oils. Average absolute errors, with respect to TAG quantitation and identification, were less than 1%. Our study identified and quantitated these TAGs present at greater than 0.1% (oil, number of TAGs): coconut, 99; palm, 27; randomized palm, 28; palm olein, 28; randomized palm olein, 29, and cocoa butter, 19. Concentrations of UUU, UUS, USS, and SSS TAGs, which can be determined accurately from RP-HPLC/APCI-MS of the actual TAG species, affected the physical properties of food formulation fats.

ACKNOWLEDGMENT

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