High Performance Liquid Chromatographic Determination of Minor Saccharides in Corn Sugar: Collaborative Study

Abstract

Abstract The official first action AOAC method for quantitative determination of saccharides in corn syrup by liquid chromatography was reinvestigated to expand its scope to products containing dextrose in excess of 98%. Because of the low levels of saccharides other than dextrose (DP1), separations are carried out only of the DP1, the disaccharides (DP2), and the tri- and higher saccharides (DP3+) on an Aminex Q15-S, calcium form, cation exchange column. Concentrations of solids in water solvent injected into the liquid chromatograph are higher than those in the AOAC method to increase precision of analysis of the minor saccharides. All carbohydrate components in solution are eluted from the column; therefore, loss of refractive index detector linearity with respect to dextrose is compensated by use of an external maltose (DP2) standard to correct for DP2 and DP3+ response and dextrose is calculated by difference from 100. With mean values of 0.520% DP2 and 0.244% DP3+, the reproducibility and repeatability coefficients of variation are 14.6 and 6.7% for DP2, and 19.3 and 11.9% for DP3+, respectively. Dextrose levels of 99.23% are reproducible within 0.161. The coefficients of variation of the DP2 component are lower by this method than by the AOAC method at levels up to 2% DP2. The method has been adopted official first action.