Cereal Chem 69:188-191   |  VIEW ARTICLE

Air Classification of Flours from Wheats with Varying Hardness: Protein Shifts.

Y. V. Wu and A. C. Stringfellow. Copyright 1992 by the American Association of Cereal Chemists, Inc. 

Air classification of wheat flour (six hard red winter [HRW], four hard red spring [HRS], and four soft wheats [SW]) produced an ultrafine fraction with a protein content of 38-54% (N x 5.7, dry basis) in 0.3- 1.5% yield and a fine fraction (less than 15 micrometers) with protein content of 21-30% in 11-25% yield. Brule, a HRW wheat with both hard and semihard kernels, produced a less than 15-micrometer fraction with the highest protein content (30%) and yield (16%) of all HRW wheats studied. The ultrafine and less than 15-micrometer fractions may have commercial potential as a protein concentrate. HRS wheat, HRW wheat, and SW classes differed in protein content of the 24- to 30-micrometer fraction, protein shift, and ratio of protein content of the less than 15-micrometer or 24- to 30-micrometer fractions to protein content of the flour.