Effects of air flow micro pulverized wheat bran dietary fiber on physicochemical, structural, and digestive properties of wheat starch

The effects of wheat bran dietary fiber (WBDF) treated by air flow micro-pulverization on gelatinization, thermal, rheological, structural properties, and in vitro digestion of wheat starch (WS) were investigated. Different particle sizes of WBDF were obtained by conventional knife grinding and airflow micro-grinding. Compared with conventional knife grinding, the particle size of WBDF treated by air flow micro-pulverization decreased, the particle size distribution was concentrated at small particle sizes, the specific surface area increased, and the hydraulic and oil-holding power decreased, which was mainly related to the change of WBDF spatial structure and the increase of solubility. At the same time, the peak viscosity, setback, breakdown, and resistant starch content short-range order degree and relative crystallinity of WS were increased by adding WBDF treated by air flow micro-pulverization, whereas the gelatinization enthalpy value and apparent viscosity were decreased. This indicated that the air micro pulverized WBDF promoted gelatinization and inhibited digestion while reducing the thermal stability of WS, leading to short-term recovery. This study provides a theoretical reference for the production and processing of gluten-containing flour products. PRACTICAL APPLICATION: In this study, the physical and chemical properties and spatial structure of air flow micro pulverized dietary fiber of wheat bran were analyzed, and its effects on the properties of wheat starch were studied. Therefore, this study provides a theoretical basis for the industrial application of gluten-containing flour products.