Alginate as a Source of Dietary Fiber

Alginate, an algal polysaccharide, is widely used in the food industry as a stabilizer, or as a thickening or emulsifying agent. As an indigestible polysaccharide, alginate may also be viewed as a source of dietary fiber. Previous work has suggested that dietary fibres may protect against the onset and continuation of a number of cardiovascular and gastrointestinal diseases. This article aims to examine what is currently understood about the fiber-like activities of alginate, particularly its effects on intestinal absorption and the colon, and therefore aims to gauge the potential use of alginate as a dietary supplement for the maintenance of normal health, or the alleviation of certain cardiovascular or gastrointestinal diseases.

Keywords:

• colonic health
• colonic microflora
• glycaemic response
• mucus

Notes

*These studies used bile acids conjugated to taurine rather than basic salts. All tests were carried out at approximately neutral pH for various lengths of time (10 min for Camire et al. (1993), 1 h for Vahouny et al. (1980) and 2 h for Wang et al. (2001)).

¹Total fiber content and the ratio of soluble:insoluble fiber were determined by a previously described chemical method (Englyst et al., 1994). n/a = not applicable. All diets were produced by adding fiber to the same basal diet (23.2% rice starch, 20% Ca-caseinate, 32.5% sucrose, 5% soya oil and 5% vitamin/mineral mix), so that there was no variation between dietary constituents between groups. Instead of 14.3% fiber, the fiber-deficient diet contained extra rice starch. There was no significant difference in the weight of feed eaten by the rats within each dietary group (p > .05 by one-way ANOVA).