Effect of ultra-high pressure treatment on structural and functional properties of dietary fiber from pomelo fruitlets

The effects of ultra-high pressure treatment on structural and functional properties of dietary fiber from pomelo fruitlets were analyzed. The results showed that ultra-high treatment changed monosaccharide composition, increased total dietary fiber and soluble dietary fiber from pomelo fruitlets, especially at 400 MPa where soluble dietary fiber was greatly increased from 32.49% +/- 0.23% to 41.92% +/- 0.32% as compared to native one (p < 0.05). Besides, ultra-high pressure treatment enhanced water-and oil-holding capacity, as well as swelling capacity of dietary fiber, which were related to its more porous structure and hydrophobic groups. Crystallinity and thermal stability of ultra-high pressure modified dietary fibers increased. Moreover, ultra-high pressure modified dietary fibers possessed stronger bile acid binding and pancreatic lipase inhibition capacities, suggesting its better potential in vitro hypolipidemic activity. Our findings suggested that ultra-high pressure treatment is a promising method to obtain dietary fiber with excellent functional properties, and can provide a basis for the high-value utilization of pomelo fruitlets as functional food with blood-lipid regulation.