Separation of molecular species of cis- and trans-triacylglycerols in trans-hardened confectionery fats by silver-ion HPLC

Smith K.W., Perkins J.M., Jeffrey B.S.J., Phillips D.L., Separation of molecular species of cis- and trans-triacylglycerols in trans-hardened confectionery fats by silver-ion High-Performance Liquid Chromatography, Journal of the American Oil Chemists’ Society, 1994, 71 (11), 1219-1222

Silver-phase high-performance liquid chromatography (HPLC) on silver nitrate-loaded silica achieves incomplete separation of major triacylglycerol (TAG) classes present in trans-hardened fats. The ”ChromSpher Lipids” silver loaded cation exchange HPLC column has been found to yield good separations of trans hardened TAG, with molecular species well resolved. Separations comparable to those previously possible for nonhardened fats are now possible for trans-hardened fats. The separation is on the basis of number and type (i.e. cis/trans) of double bonds only; the position of the double bond along the acyl group appears not to influence the separation significantly. The analysis of a palm fraction, hardened to a slip melting point of 37°C and chemically randomized, is presented as an example. This technique offers a new approach to understanding and controlling the hydrogenation and processing of trans-hardened fats.