The bifidogenic nature of chicory inulin and its hydrolysis products.

Research data on the bifidogenic effect of beta(2-1)fructans, which at present are commercialized in the U.S., Japan and Europe as food ingredients, are presented. These food ingredients originate from two different sources. Short-chain fructo-oligosaccharides are synthesized from sucrose and are composed of GFn [n beta(2-1) linked fructose moieties bound to a glucose molecule; 2 </= n </= 4]. The longer chain length molecule inulin is extracted with hot water from chicory roots (Cichorium intybus) and is also composed of GFn molecules (with 2 < n < 60). Oligofructose is a partial hydrolysate of inulin and is composed of GFn and Fm molecules (n and m indicate the number of fructose moieties with 2 </= n, m </= 7). All types of beta(2-1)fructans are well fermented by intestinal bacteria. For a given chain length, there is no difference in fermentation rate between GFn- and Fm-type beta-fructans. In vitro fermentation of inulin revealed that molecules with a chain length (degree of polymerization or DP) > 10 are fermented on average half as quickly as molecules with a DP < 10. All beta(2-1)fructans are bifidogenic and classified as biobiotics.