This study investigated the potential of wet-type grinder–treated rice bran (WG-RB) as a plant-derived hydrocolloid-like material for improving gluten-free rice bread. Rice bran, a nutrient-rich by-product of rice milling, is abundant in dietary fibers, proteins, and antioxidants but remains underutilized due to its coarse texture and poor dispersibility. To overcome these limitations, rice bran was physically modified using a wet-type grinder (WG), and the study clarified how WG-induced structural refinement enhances its functionality in rice-bread systems.

Rice bran powder (5% w/w) was processed using a Super Masscolloider through 1, 5, 10, and 15 passes (T1, T5, T10, T15). Particle size distribution, viscosity, dispersion stability, antioxidant activity, and bile acid–binding capacity were evaluated. Rice-flour bread containing 3% WG-RB was then prepared to assess fermentation behavior, batter rheology, specific volume, and crumb texture.

WG treatment substantially reduced particle size and markedly increased viscosity, resulting in improved dispersion stability—from rapid sedimentation within 20 min in untreated bran to90% of the particles remaining suspended after 24 h in T15 WG-RB.Fermentation and rheological analyses demonstrated that WG-RB enhanced gas-holding capacity and increased batter viscoelasticity, with T15 showing the highest recovery rate (69%). Bread supplemented with T15 WG-RB showed a 53% increase in specific volume and a 73–76% reduction in crumb firmness compared with the control. Image and color analyses further revealed a finer, more uniform crumb structure and increased whiteness. Together, these results indicate that WG-induced microstructural refinement substantially improves the functional performance of rice bran within gluten-free rice-bread matrices.

These enhancements are a direct result of WG-induced micronization and physical modification of rice bran, which improve its viscosity and dispersion stability. These modified properties enable WG-RB to integrate more effectively into the rice-flour matrix, thereby enhancing batter structure, stability, and gas retention during proofing and baking. The findings elucidate how microstructural modification of rice bran improves rheological and technological properties in gluten-free systems. Overall, WG treatment is a key strategy for valorizing rice bran as a clean-label, sustainable hydrocolloid-like ingredient. This not only enhances product quality but also promotes resource utilization in gluten-free breadmaking, thereby contributing to sustainable food practices