Cereal Chem 48:427 - 436.  |  VIEW ARTICLE
Pentosans Associated with Gluten.

B. L. D'Appolonia and K. A. Gilles. Copyright 1971 by the American Association of Cereal Chemists, Inc. 

A procedure was established for the isolation, purification, and fractionation of the pentosans which remain associated with the gluten fraction of wheat flour. Preliminary investigations on a large number of glutens extracted from different hard red spring wheat-flour varieties indicated that all of the glutens contained pentosan material. Included in the study were glutens extracted from durum semolina and soft wheat flour. Initially, various methods were attempted for extracting pentosans from the gluten, with the following approach finally adopted. The procedure involved sodium hydroxide extraction of the gluten followed by neutraliztion with acetic acid and subsequent contrifugation. The extract was then subjected to heating followed by centrifugation and dialysis of the supernatant. The freeze-dried crude pentosan preparation was subjected to pancreatin treatment and ethanol precipitation of further purification. DEAE-cellulose chromatography was used to fractionate the pentosans into five fractions. Fraction I was essentially an arabinoxylan with only small amounts of protein. The component sugars in the fractions were examined by paper and gas-liquid chromatography. Intrinsic viscosity and optical rotation were used to further characterize the different fractions. The results appear to indicate that the pentosans associated with gluten are similar to the pentosans extracted from flour by water. Pentosans extracted from durum glutens contained higher amounts of pentosans and appeared to have a greater degree of branching as well as a higher intrinsic viscosity.