Leys Sofie, De Bondt Yamina, Bosmans Geertrui, Courtin Christophe M
Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
Food Chem. 2020 Sep 30;325:126828. doi: 10.1016/j.foodchem.2020.126828. Epub 2020 Apr 15.
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.
采用时域核磁共振弛豫测量技术研究了小麦面团中水和生物聚合物的分子流动性以及木聚糖酶对其的影响。为降低复杂性，使用了包含淀粉、面筋和/或水不溶性阿拉伯木聚糖（WU-AX）的模型体系。在淀粉-WU-AX-水模型中，淀粉与水的结合速度快，但与WU-AX相比结合力较弱，导致静置过程中淀粉中的水被抽出。相反，在面筋-WU-AX-水体系中，尽管WU-AX的保水能力（WRC）高于面筋，但WU-AX并未影响水的分布。在淀粉-面筋-WU-AX-水模型和小麦粉中，水分布在包括WU-AX在内的不同成分中。添加木聚糖酶降低了WU-AX的WRC，导致水的释放。因此，木聚糖酶对面团和面包品质的有益作用部分可归因于最初由WU-AX结合的水在其他面粉成分之间的重新分布。
