Effect of wheat dietary fibers on properties of dough ingredient and corresponding noodles

To enhance wheat bran (WB) utilization in flour-based foods, total dietary fiber (TDF), soluble dietary fiber (SDF), and insoluble dietary fiber (IDF) were prepared via an acid-enzyme combined treatment, and their effects on the properties of starch and gluten in dough and noodle quality were evaluated in this study. The results indicated that water-holding, oil-holding, and swelling capacities followed the order: TDF > SDF > IDF > WB. SDF exhibited a loose microstructure (SEM), and facilitated conformational transitions from β-turns to β-sheets and from sulfhydryl groups to disulfide bonds. Dietary fiber supplementation (0–15%) significantly increased the onset (T0), peak (Tp), and conclusion (Tc) gelatinization temperatures of starch, while reducing viscosity properties and gelatinization enthalpy (p < 0.05), with the minimum value of 2.67 J/g for IDF. WB and TDF significantly increased the noodle hardness, chewiness and cooking loss, decreased tensile strength and water absorption capacity, with TDF exhibiting a milder effect than WB. Furthermore, compared to conventional wheat noodles, dietary fiber-enriched noodles showed increased resistant starch content and a lower estimated glycemic index (eGI), with the 15% TDF-supplemented noodles qualifying as a low-GI food. These findings suggest that wheat dietary fiber can serve as a high-quality raw material for developing low-GI food products.