Modification of dietary fibers from purple-fleshed potatoes (Heimeiren) with high hydrostatic pressure and high pressure homogenization processing: A comparative study

In this study, we evaluated the effects of high hydrostatic pressure (HHP) and high pressure homogenization (HPH) treatments on the physicochemical, functional, and structural properties of dietary fibers (DFs) obtained from purple-fleshed potatoes. DFs subjected to HHP and HPH exhibited increased content of soluble dietary fiber. HHP and HPH treatments did not improve water holding capacity, but increased oil holding and swelling capacities, and emulsion activity and stability. DFs treated with HPH showed the increased antioxidant activities (DPPH 0.89, ABTS 2.65, FRAP 3.39 mg Trolox/g DF), content of total phenol, and α-glucosidase inhibition (98.3%). HHP and HPH treatments changed monosaccharide compositions and structural characteristics of DFs. Therefore, DFs from purple-fleshed potatoes could be used as a fiber-rich ingredient in functional foods, and HPH was more useful in the modification of dietary fiber than HHP at the same treatment conditions. Industrial relevance: This article deals with the modification of dietary fibers from purple-fleshed potatoes (Heimeiren) with HHP and HPH treatments. Results suggest that HPH treated dietary fiber showed a higher ratio of soluble fraction, increased physicochemical and functional properties than HHP at 200 MPa. There outcomes could help the food industry identify the optimal high pressure processing type to improve physicochemical and functional properties of dietary fiber.