ABSTRACT
Barley cell walls are an excellent source of soluble and insoluble dietary fiber. Despite variations due to genetic and environmental factors within cereal grains, generally the content of total dietary fiber in whole barley grain (17.3%) is higher than in other cereal grains. Arabinoxylans and mixed linkage (1→3)(1→4)-β-D-glucans are the major nonstarch polysaccharides present in various tissues of barley, but other polysaccharides such as cellulose, glucomannans, and arabinogalactans also occur, although in much smaller amounts. Depending on the genotypic or cellular origin, both polymers exhibit variations in molecular features. The molecular structures of β-glucans and arabinoxylans are important determinants of physicochemical properties and may affect physiological functionality in the gastrointestinal tract. Barley β-glucans have been associated with lowering plasma cholesterol, reducing glycemic index, and reducing the risk of colon cancer. Furthermore, arabinoxylans offer nutritional benefits of soluble and insoluble fiber and, because of phenolic moieties bound to arabinoxylans, they may also have some antioxidant properties.
ArticleCopyright
This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. AACC International, Inc., 2010.