of the beta-configuration of the anomeric C2 in their fructose monomers, inulin-type fructans resist hydrolysis by intestinal digestive enzymes, they classify as &;non-digestible&; carbohydrates, and they are dietary fibres. increasing faecal biomass and water content of the stools, they improve bowel habits, but they have characteristic features different from other fibres. They affect gastrointestinal functions not because of their physicochemical propeies but rather because of their biochemical and physiological attributes. In the colon, they are rapidly fermented to produce SCFA that are good candidates to explain some of the systemic effects of inulin-type fructans.