Assessing the impact of xylanase activity on the water distribution in wheat dough: A 1H NMR study. (30th September 2020)

• Record Type: Journal Article
• Authors: Leys, Sofie; De Bondt, Yamina; Bosmans, Geertrui; Courtin, Christophe M.
• Is Part Of: Food chemistry. Volume 325(2020)
• Publication Date: 2020-09-30
• Subjects: Wheat -- Arabinoxylan -- Xylanase -- Hydration -- Time domain proton nuclear magnetic resonance -- Dough -- Water retention capacity; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2020.126828
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: 1 H NMR of dough allows determining the molecular mobility of water and biopolymers. The water retention capacity decreases from WU-AX over gluten and flour to starch. Starch binds water fast but during resting WU-AX withdraws water from starch. WU-AX withdraws less water from other components after solubilization by xylanase. Abstract: The molecular mobility of water and biopolymers in wheat dough and the influence of xylanases thereon was investigated with time domain proton nuclear magnetic resonance relaxometry. To reduce the complexity, model systems containing starch, gluten and/or water-unextractable arabinoxylan (WU-AX) were used. In the starch-WU-AX-water model, starch binds water fast but less strong compared to WU-AX, resulting in water withdrawal from starch during resting. In contrary, WU-AX did not affect the water distribution in a gluten-WU-AX-water system, despite the higher water retention capacity (WRC) of WU-AX compared to gluten. In a starch-gluten-WU-AX-water model and in wheat flour, water was distributed over the different constituents including WU-AX. Addition of xylanase reduced the WRC of WU-AX, resulting in a release of water. Therefore, the beneficial effect of xylanase on dough and bread quality can, in part, be attributed to the redistribution of water, initially bound by WU-AX, between the other flour constituents.