title: Characterization of water and alkali extractable arabinoxylan from wheat and rye under standardized conditions.
abstract: Arabinoxylans (AXs) are an important component of wheat and rye dough. They bind water, contribute to the formation of viscous dough and improve the quality of bread. For the application of AX fractions in bread making process, it is useful to record a quality profile of wheat fractions compared to the quality profile of rye fractions under standardized conditions. In this work water and alkali extractable AX containing fractions, from wheat- and rye wholemeal, were extracted under standardized conditions and characterized. For analysis of composition, structural features, and molecular dimension a combination of chemical, physicochemical, enzymatic and chromatographic techniques was applied. The molar mass distributions obtained by means of an innovative colorimetric pentose detection in the eluted SEC fractions were comparable for all under standardized conditions extracted AXs. The determined molar masses of AXs extracted both from wheat- and from rye grain were close to 2.0 × 10(5) g/mol for water extractable AXs and 3.0 × 10(5) g/mol for alkali extractable AXs. Different susceptibility to endoxylanase treatment, having been observed as differences in the SEC profiles, may be evidence of structural differences between AXs depending on their origin. The viscosities of AX solutions were strongly influenced by their molar mass and structure; samples being less susceptible to endoxylanase provided solutions of higher viscosity.
authors: Faculty of Food Technology, Department of Carbohydrates Technology, University of Agriculture Kraków, ul. Balicka 122, 30149 Kraków, Poland.
authors: Krzysztof
authors: K
authors: Buksa
authors: Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Werner
authors: W
authors: Praznik
authors: Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
authors: Renate
authors: R
authors: Loeppert
authors: Faculty of Food Technology, Department of Carbohydrates Technology, University of Agriculture Kraków, ul. Balicka 122, 30149 Kraków, Poland.
authors: Anna
authors: A
authors: Nowotna
keywords: Alkali extractable arabinoxylan; Molar mass; Solubility; Viscosity; Water extractable arabinoxylan; Wheat and rye