Cereal Chem 69:148-151   |  VIEW ARTICLE

Relation Between Wheat Kernel Hardness, Environment, and Gliadin Composition.

F. R. Huebner and C. S. Gaines. Copyright 1992 by the American Association of Cereal Chemists, Inc. 

Variation in wheat kernel hardness has recently increased, making wheat classification more difficult. To assess effects of growing conditions on protein composition and hardness, wheat grown in a greenhouse and commercial field-grown wheats were examined. Mature kernels from greenhouse plants were harvested and segregated according to origin from wheat heads. Individual kernels were tested for hardness with a particle size analyzer, and gliadins were extracted and analyzed by high-performance liquid chromatography. Chromatograms were integrated, and amounts of fractions varying in hydrophobicity were determined. For greenhouse-grown wheats, hardness correlated with at least one gliadin fraction but not with original head positions of kernels. This also was true for commercial wheats, but such samples also varied in hardness due to multiple gentoypes. Thus, differences in hardness among single kernels of a cultivar may result from variation in protein synthesis in kernels from different head locations, from variation between heads of the same plant that develop at different dates, and from multiple biotypes within cultivars.