Chapter 22 Methodology for Extraction of Soluble Non-Starch Polysaccharides and Viscosity Determination of Aqueous Extracts from Wheat and Barley

摘要

Cereal grains contain various amounts of non-starch polysaccharides (NSP), which are composed predominantly of arabinoxylans, β-glucans and cellulose. The detrimental effect of soluble NSP is mainly associated with the viscous nature of these polysaccharides and their physiological effects on the digestive medium. Our study had in view to investigate the influence of some extraction conditions on the viscosity of wheat and barley aqueous extracts. Water extract viscosities (WEV) appeared to be related to the particle size, the extraction time and temperature, and to the time elapsed after isolation of the extract. The experiments revealed as optimum conditions for obtaining the soluble NSP extract from wheat and barley and for WEV determination: granulation of 0.5 mm size, extraction temperature 40 °C, extraction time 60 min, and viscosity measurements immediately after extract isolation.