Cereal Chem 45:421 - 431. | VIEW
The Constitution of a Starch-Galactose Codextrin.
M. H. Fischer, Y. Ghali, and F. Smith. Copyright 1968 by the American Association of Cereal Chemists, Inc.
The acid- and heat-catalyzed dextrinization of amylopectin in the presence of D-galactose afforded a codextrin containing 13.5% D-galactose. Periodate and methylation studies established that D-galactose had become incorporated into a polymer, whereas isolation of 6-O-alpha-D-glucopyranosyl-alpha-D- galactopyranose from a partial acid hydrolysate of a similar codextrin provided evidence, together with the methylation data, that the D-galactose was an integral part of a glactoglucan codextrin. The initial product of the co-dextrinization was heterogeneous, as shown by the fractionation studies. Structural studies on a major codextrin fraction showed that it had an average D.P. of 37 and was highly branched, as deduced from the high proportion of tetra-O-methyl-sugars recovered from the hydrolysate of the methylated codextrin. The methylation and periodate data indicate an average repeating unit of 5 for the codextrin.