FOS vs inulin: the same family, different lengths
Fructo-oligosaccharide and inulin are both fructans — chains of fructose. The difference is how long those chains are, and that single difference changes the sweetness, the texture and how fast they ferment.
The comparison
| FOS | Inulin | |
|---|---|---|
| Chain length | Short (DP 2-8) | Long (DP up to 60) |
| Fermentation | Faster | Slower |
| Sweetness | Mild-moderate | Very mild |
| Solubility | Highly soluble | Less soluble, can gel |
| Content | ≥95% on solids | ≥90% (typical) |
| Best role | Clear beverages, fiber fortification | Fat replacement, creamy texture |
Where each one fits
FOS — the clear-drink fiber
Short chains mean FOS dissolves transparently and ferments quickly. It is the fiber you add to clear beverages, yogurt and bars when you want fortification without clouding or thickening. Its mild sweetness also helps reduced-sugar formulas.
Inulin — the texture fiber
Long chains let inulin gel and build a creamy, fat-like mouthfeel. That is the reason it shows up in low-fat yogurts, spreads and frozen desserts as a fat replacer, with almost no sweetness of its own.
The short version
Clear drinks, yogurt and fortification → FOS. Creamy texture and fat replacement → inulin. We supply organic FOS (≥95% on solids, USDA + EU certified) for the fortification side of the job.