inulintype

Inulin-type, or inulintype, refers to a class of fructan polysaccharides produced by several plant species as storage carbohydrates. These polymers are built from fructose units linked predominantly by β-(2→1) glycosidic bonds and are commonly terminated by a glucose residue at the reducing end. The degree of polymerization (DP) varies widely, from short oligomers to long chains, and influences solubility and fermentability.

Inulintype carbohydrates occur in high concentrations in species such as chicory (Cichorium intybus), Jerusalem artichoke, dandelion, and agave. They are synthesized in plant roots or rhizomes via fructosyltransferase enzymes that extend existing carbohydrate chains on sucrose acceptors. As storage carbohydrates, they accumulate during growth and are mobilized when needed.

Humans cannot digest inulintype due to the lack of relevant glycoside hydrolases, so these polymers reach the colon where they are fermented by the gut microbiota. They act as prebiotics, promoting beneficial bacteria such as Bifidobacteria and producing short-chain fatty acids that may support gut health. Their solubility, sweetness, and rheological properties depend on DP, making them useful as dietary fiber ingredients and functional food additives.

Regulatory status is generally favorable in many jurisdictions, with inulin-type fructans commonly recognized as safe when used within typical intake ranges. Potential drawbacks include gastrointestinal effects at high intake and considerations for individuals following low-FODMAP diets.

See also: inulin, fructan, prebiotic.