Effect of dynamic high‐pressure microfluidization on the physicochemical and structural properties of insoluble dietary fiber from fresh corn bract

Abstract

Fresh corn bracts were used as raw materials to prepare dietary fiber, dynamic high-pressure microfluidization technology (DHPM) was then conducted to modify the fresh corn bract insoluble dietary fiber (FCBIDF) to explore its effect on the physiochemical properties and structural characteristics of FCBIDF. Results showed that in the pressure range of 80–180 MPa, the water-holding capacity, water-swelling capacity, and oil-holding capacity of the dietary fiber of fresh corn bracts treated by DHPM significantly increased. When the DHPM pressure was 180 MPa, compared with the untreated group, they increased by 75.56%, 118.04%, and 78.58%, respectively. The particle size for FCBIDF treated by DHPM obviously reduced. The SEM images of the sample showed the loosened surface structure, the honeycomb-like porous feature appeared. Differential scanning calorimetry analysis demonstrated the enthalpy value of FCBIDF significantly reduced, and its thermal stability destroyed. XRD and FTIR analyses indicated the relative crystallinity of FCBIDF declined and some cellulose components redistributed and transformed into soluble dietary fiber. Those results provided a useful reference for physically modifying insoluble dietary fiber and increasing the added value of fresh corn bracts. Novelty impact statement Dynamic high-pressure microfluidization (DHPM) technology improved the water-holding capacity, water-swelling capacity, and oil-holding capacity of fresh corn bract insoluble dietary fiber (FCBIDF). The surface of FCBIDF treated by DHPM appeared holes and cracks, and the particle size decreased. The relative crystallinity of FCBIDF declined and some cellulose components redistributed and transformed into soluble dietary fiber after DHPM.