Isolation and characterization of cellulose/arabinoxylan residual mixtures from corn fiber gum processes

White, fluffy cellulose/arabinoxylan mixtures (CAX) were generated from the solid residues remaining after corn fiber gum (CFG) production. Most CAX were produced using variations of a process in which a single alkaline hydrogen peroxide (AHP) step was used for delignification and for CFG (arabinoxylan) extraction. The optimal ratio of H2O2 to corn fiber to water was 0.1:1:20. Holding this ratio constant, time and temperature conditions were systematically varied and yields of CAX and CFG determined. Parallel processes were conducted without H2O2 to determine its effect on CAX and CFG yield. CAX prepared under identical conditions but without H2O2 retained nearly twice the levels of CFG sugars, as revealed from carabinose, D-xylose, and D,L-galactose levels. Even the CAX prepared under extreme AHP conditions (1 hr, 100 degreesC), however, contained 32.9% of these CFG sugars. This CAX was obtained in a 25.1% yield whereas those produced under less vigorous conditions were obtained in higher yields, because they retained more CFG. CAX prepared in the presence of H2O2 hydrated very effectively, as indicated by their high swollen volumes and water absorbance values. This suggests potential food applications for CAX as a bulking agent. In addition, the open structure of the CAX matrix would render these residues suitable for chemical derivatization and enzymatic saccharification.