Wheat polysaccharides and gluten effect on water migration and structure in noodle doughs: An 1H LF-NMR study

Noodle dough is a complex system formed by the effects of external forces on water, starch, gluten, arabinoxylan. The migration of water among wheat flour ingredients affects dough structure and the processing and quality of wheat noodles. Spontaneous water molecule migration depends on competitive water absorption among different components, whereas the regularity and mechanism remain unclear. This study investigated the interaction of water molecules with flour ingredients. LF-NMR indicated that starch, with the largest content in flour, smallest contact angle, and uniform particles, shifted the hydrogen proton peaks towards short T2 direction and narrowed the width of peaks. In addition, SEM showed the compactness and filling capacity of starch, accounted for its ability to uniformize water distribution (MRI). Gluten and arabinoxylan had stronger water trapping capacity, dispersed particles, and a loose and viscoelastic network structure that altered the water properties within dough. Spontaneous water molecule migration established a dynamic equilibrium between starch attraction and gluten-arabinoxylan constraint, providing dough for subsequent stages of noodle-making process.