Insight into the quality and structural mechanism of wheat noodle fortified with broken rice flour

Broken rice is a by-product of rice milling and has not been widely utilized. The study investigated the effects of broken rice flour (BRF) on wheat flour (WF), with a focus on its impacts on the physicochemical properties and structure of noodles. With the increase in BRF addition, the protein content in the BRF-WF flour decreased from 10.63% to 9.76%, while the starch content increased from 73.73% to 75.18%, the peak viscosity increased. At 15% BRF, the wet gluten content and gluten index of the BRF-WF flour increased by 1.81% and 6.93%, respectively. The incorporation of BRF led to a reduction in the contents of glutenin macropolymer and disulfide bonds in noodles, while the proportion of β-sheet conformation increased. The starch crystallinity of uncooked and cooked noodles was enhanced by 50.82% and 144.10%, respectively. The short-range order showed no significant change.The storage modulus (G') and loss modulus (G″) of noodles increased initially and then decreased with the incorporation of BRF. At 15% BRF, the starch dispersedly embedded in the gluten network. When BRF exceeded 15%, resulted in gluten network disruption and starch aggregation. Compared with WF noodles, 15% BRF increased the hardness and elasticity of noodles by 2.46% and 2.17%, and enhanced the noodle lightness. This study provides a theoretical foundation for developing high quality grain noodles.