Cereal Chem 42:1 - 14.  |  VIEW ARTICLE

Automated Determination of the Dextrose Equivalent of Corn Starch Hydrolysates.

L. D. Ough and N. E. Lloyd. Copyright 1965 by the American Association of Cereal Chemists, Inc. 

Dextrose equivalent (DE) is the criterion employed by the corn wet-milling industry to indicate the extent of hydrolysis of starch in the manufacture of corn syrups and sugars. It is defined as the percentage of reducing sugars calculated as dextrose and expressed on a dry-substance basis. Reducing sugars are determined by the method of Lane and Eynon, which specifies an alkaline copper tartrate reagent. The present work shows how DE can be determined by an automated procedure with the Technicon Auto-Analyzer. In this procedure, consecutive reducing sugar determinations are made on the sample before and after hydrolysis with hydrochloric acid. Reducing sugars are determined with reagents made with potassium ferricyanide, potassium cyanide, and sodium hydroxide. The quantity found before hydrolysis (x) is related to reducing sugar content, and that after hydrolysis (y) is a function of the carbohydrate dry substance. The DE is related to the two determinations as follows: DE = (ax)/(y + bx), where a and b are constants. The procedure was applied to corn starch hydrolysates and to various sugars and related compounds.