Impact of arabinoxylan with different molecular weight on the thermo-mechanical, rheological, water mobility and microstructural characteristics of wheat dough

The aim of this study was to investigate the effects of arabinoxylan with different molecular weight on the wheat dough thermo-mechanical, rheological, microstructural and water mobility properties. Arabinoxylan was extracted from wheat bran and hydrolysed by endo-1,4--xylanase (EC 3.2.1.8 from Trichoderma reesei, 10000Ug(-1)) for 2min (AX(M)) and 10min (AX(L)), respectively. The addition of hydrolysed arabinoxylan AX(L) increased the stability time, decreased the setback value of wheat dough and enhanced the values of storage modulus (G) and loss modulus (G), while unhydrolysed arabinoxylan (AX(H)) reduced these values. Meanwhile, unhydrolysed arabinoxylan increased T-2 relaxation time while hydrolysed arabinoxylan AX(L) decreased T-21 and T-22. Confocal laser scanning microscope (CLSM) results showed that the addition of hydrolysed arabinoxylan AX(L) promoted the formation of a more compact and continuous protein network in wheat dough. These results revealed that compared with high molecular weight arabinoxylan, hydrolysed arabinoxylan could improve the rheological properties and processing properties of wheat dough by enhancing the interaction among water molecules, starch and gluten in wheat dough.