Publication no. C-2000-0602-05R |  VIEW ARTICLE

Air Classification of Barley Flours.

A. A. M. Andersson (1,2), R. Andersson (1), and P. Åman (1). (1) Swedish University of Agricultural Sciences, Department of Food Science, P.O. Box 7051, SE-750 07 Uppsala, Sweden. (2) Corresponding author. E-mail: <annica.andersson@lmv.slu.se> Phone: +46 (0)18-67 20 48. Fax: +46 (0)18 67 29 95. Cereal Chem. 77(4):463-467. Accepted March 6, 2000. Copyright 2000 American Association of Cereal Chemists, Inc.

Flour samples from seven different barleys, including covered and naked barleys and barleys with normal, waxy, and high-amylose starches, as well as the high fiber barley Prowashonupana, were impact-milled and air-classified in a pilot unit. Six fractions (F1-F5 and C5) with increasing particle size were obtained from each barley. All fractions were analyzed for ash, protein, starch, dietary fiber, and total and unextractable beta-glucan. Ash was enriched in C5; covered barleys (4.3-5.7% of dry matter) had a higher ash content than naked barleys (2.1-3.2%). Starch was enriched in F4 for normal and waxy barleys (72-79%) and in F3 for high-amylose barleys (72-75%). Protein was enriched in F1 (14-26%) for the different barleys. beta-glucan was enriched in F5 and C5 (7-23%), Prowashonupana had the highest value. The extractability of beta-glucan decreased with increasing particle size, probably because of lower amounts of endogenous beta-glucanase and poorer availability of the substrate in larger particles.