Chemical composition of barley samples focusing on dietary fibre components

Grain samples of 16 barleys, including covered and naked types, were selected to represent genotypes that were known to vary in their contents of protein, amylose and amylopectin and beta-glucan contents of wort or grain. The chemical compositions of the samples were analysed, focusing particularly on dietary fibre components. Covered and naked barley genotypes differed in their average contents of non-starch polysaccharides, Klason lignin and ash. High amylose types had higher total beta-glucan values (6.3% and 7.9%) than waxy types (5.4%-5.8%). The content of extractable beta-glucan was only slightly correlated with total beta-glucan content. On average, 44% of the xylose residues in water extractable arabinoxylans were substituted with arabinose residues. The presence of considerable amounts of xylopyranose substituted only at O-2 was detected in water extractable arabinoxylans. (C) 1996 Academic Press Limited