What it is
Fructans are chains of fructose units, and in commercial prebiotic fibre the only meaningful variable is how long those chains are. Extraction from chicory root yields a native mixture spanning a wide degree of polymerisation, which is then separated into fractions: enzymatic hydrolysis produces short-chain oligofructose, while physical fractionation isolates the long-chain material. The same raw stream therefore produces ingredients that behave quite differently.
Formulation considerations
Chain length determines sweetness, solubility and texture together. Short-chain FOS dissolves quickly, sweetens mildly and adds little viscosity, which makes it useful where fibre needs to disappear into a formulation. Long-chain inulin adds body and a creamy mouthfeel in water, and at higher concentrations will form a soft gel that formulators use deliberately as a texturiser. Neither contributes much to the sweetness budget in the way sucrose does, so sweetener systems usually need separate attention.
The chemical caution is hydrolysis. Acidic conditions plus heat break the glycosidic linkages, releasing free fructose and reducing the fibre figure that appears on analysis. This matters most in hot-filled acidic beverages held for long shelf lives, and it is worth measuring on the finished product rather than assuming the incoming specification carries through.
Hygroscopicity is the handling caution: these powders pull moisture and cake, so sealed storage and prompt resealing are routine.
Applications
Beverage powders, drink mixes, sachets and nutritional blends use the soluble grades directly. Bars, baked goods and dairy-style products use longer-chain material for texture as well as fibre. In solid dose the powders also serve as carriers and fillers. Available in bulk quantities, with pricing on application.
Applications
- Beverage and drink mix powders
- Powder blends and sachets
- Bars, baked and dairy-style formats
- Tablets and capsules as a carrier or filler
Handling and storage
Store sealed below 25 degrees Celsius at low humidity. The powders are hygroscopic to varying degrees and will cake if left exposed, with FOS grades noticeably more moisture sensitive than long-chain inulin. Typical shelf life is 24 to 36 months from manufacture in unopened packaging. In processing, note that fructans hydrolyse under combined low pH and elevated temperature, so extended hot holds in acidic liquid systems will reduce measured fibre content; long-chain grades are more resistant than short-chain.
Common questions
What is the difference between inulin and FOS?
Both are fructans, and the distinction is chain length. FOS or oligofructose has a low degree of polymerisation, dissolves very readily and carries roughly 30% of the sweetness of sucrose. Long-chain inulin has a higher DP, contributes almost no sweetness and builds viscosity and body instead.
Which grade works best in a beverage?
Short-chain FOS and high-solubility inulin grades dissolve fastest and give the clearest solutions, which suits ready-to-drink and instant mixes. Long-chain inulin can be used where some body is wanted, but it dissolves more slowly and can haze a clear beverage at higher inclusion.
Is inulin stable in acidic products?
Fructans hydrolyse when low pH and heat are combined, so a hot-filled acidic beverage will lose some measured fibre over shelf life. Long-chain grades resist this better than short-chain, and keeping high-temperature hold times short limits the effect.
How is the fibre content determined?
Dietary fibre is quantified by recognised AOAC methodology appropriate to fructans, and the figure is stated on the lot Certificate of Analysis alongside the inulin or FOS content on a dry basis.