Tool 02 · High acyl or low acyl?
Gellan Gum Grade Selector
Five questions about texture, ions, clarity and process temperature, and a recommendation of high acyl, low acyl or a blend — with the reasoning shown.
Before you use these numbers
- Gellan gum is dosed by outcome, not by rule: the same polymer behaves differently at a different water hardness, total solids, grade and fill temperature.
- Low acyl gellan gum needs a divalent cation to gel, so a soft-water system will thicken without setting however much is added.
- Dosage ranges on this site describe where most products land; they are a starting point for a bench trial, not a specification.
- The authoritative figures are the specification in the Technical Handbook §4 and the limits in the Method of Analysis Appendix B.
A grade recommendation is a starting point, not a specification. Confirm it with a bench trial against the actual grade and the actual process.
Already published on E418.org
Fallback
The decision table
If you would rather read than answer.
| What you need | Grade | Why |
|---|---|---|
| Suspension, body, or a thin fluid gel | Low acyl | Not a structural gel — it needs a yield stress, not strength. |
| Firm, brittle, clean-breaking gel | Low acyl | The classic application. Heat stable, ion responsive, clear. |
| Soft, elastic, cohesive gel | High acyl | Elasticity is the point of the grade — not a wide melt gap, since high acyl sets and melts over much the same window. |
| Must survive UHT, retort or baking | Low acyl | High acyl melts between roughly 70 and 80 °C and will not survive a retort. |
| Heavy calcium or magnesium load | High acyl, or low acyl plus a sequestrant | HA is ion tolerant; LA needs a sequestrant to avoid pre-gelation. |
| Clarity is a specification point | Low acyl | Clearest gels, and the easiest to hydrate without haze. |
| Soft texture and heat stability in one product | Blend | 20–40% low acyl in a high acyl base tightens the gel without losing the chew. |
Other tools
Keep going
Three more decision aids for the same problem set.