Abstract
The objective of this study was to investigate the effects of superfine grinding on the physicochemical and antioxidant properties of oat bran polysaccharides (OBP). The solubility of OBP increased from 8.1 to 11.3 mg/mL. The average molecular weights of raw OBP (rOBP) and superfine ground OBP (sOBP) were 655.6 and 489.6 kDa, respectively. The intrinsic viscosity of sOBP (4.58 mL/mg) was extremely lower than that of rOBP (94.75 mL/mg). The endothermic enthaphy change (ΔH) values of OBP with different water contents (0%, 50%, and 75%) changed from −328.79 J/g, −942.41 J/g, and −1.94 kJ/g to −197.01 J/g, −703.29 J/g, and −1.50 kJ/g, respectively. After being superfine grinding treated, sOBP exhibited higher antioxidant activities than rOBP based on FRAP, DPPH radical scavenging, and ABTS radical scavenging activities. The results suggested that superfine grinding treatment enhanced OBP's antioxidant activities. Physicochemical properties, including molecular weight, monosaccharide composition and solubility were key factors in OBP's antioxidant activities.
