Cereal Chem 38:113 - 121.  |  VIEW ARTICLE

Histochemical Characterization of Wheat and Wheat Products. III. Use of Methyl Green in Estimating Flour Extraction Rate.

Y. Pomeranz and J. A. Shellenberger. Copyright 1961 by the American Association of Cereal Chemists, Inc. 

The quantity of bran in flour may be determined by its high adsorption of methyl green. Flour is shaken with a dilute solution of methyl green, and the dye adsorbed is calculated from the absorbance of the centrifuged supernatant solution.The estimates of bran in flour, as determined by the proposed method, are highly correlated with the ash content or the color grade of the flour. Staining of flour with methyl green has also been shown useful as an aid in detection of insect fragments, especially in high-extraction flours.