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Most pseudocereal dietary fiber polysaccharides such as xyloglucans and pectins are composed of heterogeneous and complex structural elements. Arabinans, which are neutral side chains of pectins, are particularly important and represent up to 35 % of the non-starch polysaccharides. Thus, the structures of these polysaccharides may greatly influence the physiological and technological properties of the fiber. The main structural elements of these polysaccharides are only accessible through time-intensive methods such as methylation analysis. These conventional methods of carbohydrate analysis are based on chemical cleavage of all glycosidic bonds, which results in a partial information loss of complex structural elements such as ß-arabinose units. Thus, a time efficient NMR-spectroscopic approach was developed to analyze the structural composition of arabinans. Insoluble arabinans were partially solubilized by <i>endo</i>-arabinanase, which selectively cleaves the linear areas of the arabinan backbone. To analyze the portions of the different structural elements in solubilized and soluble arabinans, specific marker signals in the HSQC-spectra of the oligo- and polysaccharides were used. The marker signals were evaluated by using previously isolated and well-characterized standard compounds. To study the applicability of the method, the arabinan structures of amaranth, quinoa, and buckwheat dietary fiber were analyzed. The portions of the main structural elements obtained from the developed approach were comparable with methylation analysis data. In addition, complex structural elements such as ß-arabinoses can be analyzed, thus combining an increased information content with a reduced analysis time. The NMR-spectroscopic approach was also successfully applied to analyze pectic galactans and could also be used to analyze other pseudocereal non-starch polysaccharides.