Skip to main content
SLU publication database (SLUpub)

Research article2009Peer reviewed

Content and Molecular-Weight Distribution of Dietary Fiber Components in Whole-Grain Rye Flour and Bread

Andersson, Roger; Fransson, Gunnel; Tietjen, Markus; Aman, Per


Content of dietary fiber and dietary fiber components in whole-grain rye (n = 18) were analyzed. The average total content, when fructan was included, was for dietary fiber 19.9% (range of 18.7-22.2%) and for extractable dietary fiber 7.4% (range of 6.9-7.9%). Arabinoxylan was the main dietary fiber component, with an average total content of 8.6%, followed by fructan (4.1%). During baking of whole-grain rye bread, only small changes in total content of arabinoxylan, arabinogalactan, and beta-glucan occurred, while the content of resistant starch increased and the content of fructan decreased in a baking-method-dependent manner. The molecular-weight distribution of extractable arabinoxylan in the flour was analyzed with a new method and ranged from 4 x 10(4) to 9 X 10(6) g/mol, with a weight average molecular weight of about 2 x 10(6) g/mol. During crisp bread making, only a limited degradation of arabinoxylan molecular weight was detected, while a notable degradation was observed in sour-dough bread. The molecular weight of extractable beta-glucan in the whole-grain rye flour ranged from 10(4) to 5 x 10(6) g/mol, with a weight average molecular weight of 0.97 x 10(6) g/mol. During bread making, the molecular weight of the beta-glucan was substantially degraded.


Rye kernels; rye bread; dietary fiber; arabinoxylan; beta-glucan; molecular weight

Published in

Journal of Agricultural and Food Chemistry
2009, Volume: 57, number: 5, pages: 2004-2008
Publisher: American Chemical Society