Cereal Chem 49:609 - 615.  |  VIEW ARTICLE
Comparison of the Kjeldahl, Dye-Binding, and Biuret Methods for Wheat Protein Content.

W. T. Greenaway. Copyright 1972 by the American Association of Cereal Chemists, Inc. 

The Kjeldahl, Udy dye-binding, and biuret methods have been compared by testing 367 samples of all wheat classes. It was shown that although the Johnson versions of biuret and Kjeldahl methods do not differ significantly for wheat classes, the dye-binding method does differ from the Kjeldahl for all classes except Hard Red Spring. Most mean differences were small, being less than 0.5% between dye-binding and Kjeldahl values, except for wheats of less than 10% protein content, which differed by approximately 1%. When a quadratic equation was developed from the data and used to prepare a new conversion table, dye- binding values were brought into good agreement with Kjeldahl and biuret values.