Cereal Chem 44:281 - 287.  |  VIEW ARTICLE
Influence of Commercial Processing on Composition and Properties of Corn Zein.

J. A. Boundy, J. E. Turner, J. S. Wall, and R. J. Dimler. Copyright 1967 by the American Association of Cereal Chemists, Inc. 

The chemical and physical properties of two commercial preparations of corn zein were compared with those of zein prepared in the laboratory by direct extraction of the grain with 70% ethanol. The three zeins differed in content of sulfur amino acids, disulfide sulfur, and total sulfur and in their electrophoretic mobilities on starch gel. Evidently, commercial steeping of corn grain in sulfur dioxide before milling cleaves disulfide bonds, thereby disrupting disulfide-linked intermolecular aggregates in native zeins. Sulfurous acid-treated zein may contain S-sulfocysteine residues, as indicated by high sulfur content and low electrophoretic mobility. A commercial zein subjected to alkaline treatment so as to render its solutions more stable had less cystine and total sulfur than the native protein.