Structure, physicochemical properties and adsorption function of insoluble dietary fiber from ginseng residue: A potential functional ingredient

Abstract

The insoluble dietary fiber from ginseng residue (ginseng-IDF) was extracted using the AOAC (Association of Official Analytical Chemists) method with content of 68.61%. Ginseng-IDF had a polysaccharide content of 18.87%, uronic acid content of 7.85%, protein content of 6.52%, and had ideal water-holding capacity (17.66 g/g), swelling ability (15.05 mL/g), and oil-holding capacity (1.78 g/g). Scanning electron microscope, Fourier transform infrared spectroscopy, and X-ray diffraction analyses suggested that ginseng-IDF had the typical structures of hydrolysis fiber, polysaccharide functional groups, and crystal structure of cellulose. Different fiber components give ginseng-IDF a specified range of pyrolysis temperature, and it is suitable for application in food processing lower than 300 °C. In addition, ginseng-IDF exhibited notable glucose and sodium cholate adsorption, significantly improved nitrite adsorption at pH 2.0 and cholesterol adsorption at pH 7.0. The above results show that ginseng-IDF could be used as an ideal functional ingredient in food processing.

Keywords: Adsorption function; Composition; Ginseng residues; Insoluble dietary fiber; Physicochemical properties; Structure.