Cereal Chem 65:9-12   |  VIEW ARTICLE

Effect of the Source of Fiber in Bread on Intestinal Responses and Nutrient Digestibilities.

G. S. Ranhotra, J. A. Gelroth, and P. H. Bright. Copyright 1988 by the American Association of Cereal Chemists, Inc. 

Young rats were fed one fiber-free and 12 isofibrous diets for three weeks. Fiber originated from 12 different types of breads. Five (white, oatmeal, corn, and two multigrain) of these contained one-fifth or more of the total fiber as soluble fiber. The following results were obtained: a) fiber caused a significant increase in stomach and colon weights; b) fiber increased the dry fecal weight three- to sixfold; c) insoluble fiber was positively correlated with fecal output (r = 0.56); d) cellulose added to bread was more resistant to colonic degradation than naturally occurring insoluble fiber; e) fecal density was lower on cellulose- containing, bran-containing, and wholewheat breads than on other breads; f) fiber degradation averaged the highest (82.1%) on white bread and the least (15.9%) on cellulose-containing bread; g) apparent digestibility of nitrogen and fat was adversely affected by fiber; and h) fiber caused a significant reduction in fecal pH.