Cereal Chem 69:469-471   |  VIEW ARTICLE

Beta-Glucan Content and Viscosities of Barleys and Their Roller-Milled Flour and Bran Products.

R. S. Bhatty. Copyright 1992 by the American Association of Cereal Chemists, Inc. 

Total beta-glucan, soluble beta-glucan, and acid extract viscosity (AEV) of different barleys and their roller-milled products (flour and bran) were determined. Barley genotypes containing low or normal beta- glucan (3.8-4.1%) and low AEV (4-5 centiStokes [cS]) or high beta-glucan (6.9-7.2%) but medium (51-55 cS) or high (276-290 cS) AEV are reported. The soluble beta-glucan content and AEV of malting barleys were significantly higher than those of the feed barleys examined. In 15 diverse cultivars and genotypes of barley dry-milled in an Allis-Chalmers experimental mill, mean milling loss was 7.1% and flour and bran yields were 69.6 and 30.3%, respectively, of the recovered product. Beta-glucan varied from 4.3 to 11.3% in barley, from 3.9 to 9.0% in flour, and from 4.9 to 15.4% in bran, and the beta-glucan enrichment in bran was, on average, 1.36-fold. About 95% of barley beta-glucan was recovered in the flour and bran fractions (56% in flour and 39% in bran). Milling adjustments can be made to produce coarse, medium, and fine barley flour or bran. Of the three screen sizes tested, the highest bran yield and maximum enrichment of beta-glucan was obtained by using a 64 GG (236-micrometer) screen.