Carrageenans

Abstract

Carrageenans are linear, sulfated polysaccharides extracted from red algae and containing repeated disaccharide units composed of β-(1→3)-D-galactopyranose and a- (1→4)-D-galactopyranose or a-(1→4)3,6-anhydro-D-galactopyranose. Carrageenans have a broad rheological spectrum, rangingfrom a viscous thickener to thermally reversible gels, which may be elastic or brittle. Theinternational market for carrageenansis estimated at $450million per year, with applications mainly in the food industry, and cosmetic and pharmaceutical preparations. However, several studies show that carrageenanshave antioxidant, anti-inflammatory, antitumor, immunomodulatory, and anticoagulant activities. In this chapter, we will describe the various properties of this polysaccharide.