The Use of Freezing‐Point Depression for the Theoretical Dextrose Equivalent Measurement

Abstract

Abstract The determination of the theoretical dextrose equivalent was investigated, by measuring the osmolality (mol dissolved particles/kg H 2 O) by freezing‐point depression. Relations for dextrose equivalent and increase in dry weight during a hydrolysis were derived as a function of molality and amount of dry weight at the start of the hydrolysis. With freezing‐point depression it was possible to determine the theoretical dextrose equivalent of oligosaccharides (dextrose to maltoheptaose), whereas a traditional titration method ( Luff‐Schoorl ) overestimates 20‐50%. The relation for the increase of dry weight during the hydrolysis of starch with an α‐amylase was experimentally validated. The overestimation of dextrose equivalent by Luff‐Schoorl titration was also evident in the hydrolysis of amylopectin potato starch. With freezing‐point depression it was possible to determine the theoretical dextrose equivalent fast and accurate.