Abstract: Embodiments of the present invention report compositions, systems and methods for obtaining xylo-oligosaccharide-rich extracts from agricultural by-product streams. In certain embodiments, compositions and methods are directed to producing xylo-oligosaccharide-rich extracts with increased amounts and/or concentrations of degrees of polymerization (DP) of 3 or greater (DP3+). In other embodiments, compositions and methods relate to the production of products containing high soluble fiber, for example, xylo-oligosaccharides of DP3 or greater, from oat hull by-products. In yet other embodiments, xylo-oligosaccharides-rich extracts derived from oat hulls can be further processed to generate useful liquids for example, liquids containing soluble solids and powdered sweeteners and other useful consumer products.