Cereal Chem 41:514 - 522.  |  VIEW ARTICLE

High-Protein Rice Flours.

D. F. Houston, A. Mohammad, T. Wasserman, and E. B. Kester. Copyright 1964 by the American Association of Cereal Chemists, Inc. 

High-protein flours have been prepared by two types of commercial machinery from both normal and high- protein rice. One process, consisting of fine-grinding and air-classification, furnished 8 to 10% of the kernels as flour with about 75% higher-protein, intermediate fractions, and 75 to 80% residual flour with slightly less protein than the original. Protein content was highest in the finest particles and decreased with increasing particle size. Fat, ash, thiamine, riboflavin, and amylase activity were distributed in like manner. The second process was scouring off consecutive layers of milled rice in a continuous-flow abrasive cone mill similar to a rice-whitening cone. Flour from the outermost layers had about twice the original protein content of the whole kernels, and was obtained in 10 to 15% yield. The residue was chiefly whole kernels of slightly reduced size and protein content, with some broken kernels. Again, fat, ash, thiamine, riboflavin, and amylase activity followed the trend of protein content. Fine-grinding and air-classification of flours obtained by abrasive milling further concentrated protein in the finest-particle fractions.