Premium
NON‐STARCHY POLYSACCHARIDES OF CEREAL GRAINS I. FRACTIONATION OF THE BARLEY GUMS
Author(s) -
Preece Professor I. A.,
Mackenzie Dr. K. G.
Publication year - 1952
Publication title -
journal of the institute of brewing
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.523
H-Index - 51
eISSN - 2050-0416
pISSN - 0046-9750
DOI - 10.1002/j.2050-0416.1952.tb02702.x
Subject(s) - fractionation , solubility , chemistry , endosperm , polysaccharide , arabinose , food science , xylan , galactan , chromatography , xylose , organic chemistry , biochemistry , fermentation
Ammonium sulphate fractionation of barley extracts prepared under conditions which obviate enzyme action allows the preparation of a laevorotatory glucosan uncontaminated by pentosan and of a number of pentosan‐rich fractions (contaminated by glucosan). The properties of the pentosan materials are consistent with their being mixtures of xylan, araboxylan and araban each at varying degrees of molecular complexity and of solubility. Malting leads to the substantial elimination of the laevorotatory glucosan, but increases somewhat the recoverable yields of high‐molecular pentosan, increase being particularly marked with arabinose‐based units. The enzymic changes involved in malting lead to a decrease in viscosity of aqueous solutions of the gums, to increased water solubility, and to a conversion of the isolated gums from a fibrous to a pulverulent condition. Both barley and malt contain galactan, but mannan has been detected in barley only.