The effect of different modification methods on the structural and functional characteristics of corn bran

ABSTRACT : In this study, steam explosion (SE), composite enzymatic hydrolysis (CE), and their sequential combination (SE+CE) were applied to modify corn bran (CB) to improve soluble dietary fiber (SDF) yield and functional properties. Both SE and CE significantly increased SDF content, raising it from 2.81% to 9.83% and 3.19%, respectively. Moreover, a mild SE treatment (1.0 MPa, 30 s) combined with subsequent enzymatic hydrolysis resulted in a notable synergistic effect, achieving an SDF content 113.39% greater than SE alone. In addition to enhancing SDF yield, the sequential SE+CE treatment markedly improved essential functional properties, especially water-holding capacity (WHC) and cholesterol adsorption capacity (CAC), highlighting its considerable potential for use in functional foods. Microscopic and physicochemical analyses revealed that the combined treatment disrupted cell wall integrity, reduced particle size, and increased the exposure of hydrophilic sites, thereby enhancing hydration and adsorption capacities. Consequently, modified CB exhibited improved water- and oil-holding capacities, adsorption of glucose and cholesterol, as well as binding of sodium cholate and nitrite. Overall, these results demonstrate that the SE+CE strategy is an effective approach to enhancing the nutritional and functional value of CB for potential application in functional foods. • Steam explosion and enzymatic hydrolysis increase SDF yield in corn bran. • Sequential SE+CE treatment shows a synergistic 113.39% increase in SDF yield. • Combined modification disrupts cell walls and enhances surface hydrophilicity. • Modified corn bran improves hydration, adsorption, and antioxidant capacities. • This strategy sustainably valorizes corn bran as a functional food ingredient.