ABSTRACT
Cereal arabinoxylans (AX) were first described in 1927, by W. F. Hoffmann and R. A. Gortner, as a viscous gum present in wheat flour. AXs are minor constituents of whole cereal grains, but are significant components of plant cell walls. The thin walls surrounding the cells in the starchy endosperm and aleurone layer of most cereals consist mainly of AXs, with the exception of endosperm cell walls of barley and rice. The molecular structure of the physiologically active polysaccharides of psyllium husk is somewhat exceptional. AXs are not digested in the small intestine, but supply fermentable carbon resources for bacteria that inhabit the large bowel. In addition, AX content may differ based on genetic and other environmental factors. Polysaccharides such as gums, oat β-glucan, and AX have been studied for their physicochemical properties and have been extensively used as improvers in bread-making.
