The sugars, including arabinose, rhamnose and uronic acid, constituted up to 21.2–25.8% of the total sugars, suggesting the presence of arabinose-rich pectic substances. The xylose-containing polymer in the insoluble FRFs could possibly be a xylose-rich hemicellulose, comprising xylose, arabinose, galactose, glucose and mnannose. A hemicellulose rich in xylose was reported to he the major polysaccharide in grape seed DF. Table 3 shows a great similarity in the polysaccharide profiles among the three insoluble FRFs. In the SDF (Table 3), arabinose, rhamnose and uronic acids accounted for 53.0% of the total sugar content,implying that the arabinose-rich pectic substances were the major polysaccharides in the SDF.