A simplified method for extracting water‐extractable arabinoxylans from wheat flour

Abstract

AbstractBACKGROUND: Water‐extractable arabinoxylan (WEAX) is a minor constituent of wheat grain which influences the properties of wheat dough and its end products while conferring numerous health benefits. Consequently, various applications have been proposed for it in foodstuffs. Fortification of food products with pure WEAX extracts represents a simple means to evaluate its effect in these systems. However, rapid methods to isolate relatively pure WEAX are not available. This study aimed to develop a rapid, technically simple means to extract relatively pure WEAX on a small scale.RESULTS: A simplified process was developed to extract WEAX from wheat flour. After heating, flour WEAX was extracted with water and starch was eliminated by digestion with amyloglucosidase. Most of the protein was removed by adsorption to bentonite and precipitation with 65% ethanol. The final product generated by the developed method consisted of 93 ± 4% arabinoxylan. The WEAX yield was 0.43 ± 0.02% (0.43 ± 0.02 g WEAX/100 g of starting flour) which is higher than that of other methods that generate WEAX of similar purity.CONCLUSION: This method provides a technically simple means to perform small‐scale isolation of WEAX that contains no detectable contaminating protein. This attribute renders it a preferred input for studies assessing the impact of WEAX fortification on food product quality. Copyright © 2008 Society of Chemical Industry