What Is Gellan Gum?
Gellan gum is a water soluble, high molecular weight polysaccharide gum that is produced through the fermentation of carbohydrates in algae by the bacterium Pseudomonas elodea.
This fermented carbohydrate is purified with isopropyl alcohol, then dried and milled producing a powder.
Gellan gum is used as a stabilizer, emulsifier, thickener and gelling agent in cooking. Aspics and terrines are only some dishes which use gellan. It comes in both high acyl and low acyl forms. High acyl gellan gum produces a flexible elastic gel, while low acyl gellan gum will give way to a brittle gel.
Like many other hydrocolloids, gellan gum is used with liquids. The powder is normally dispersed in the chosen liquid to dissolve it. Dosage for this begins at 0.1%, depending on the type of gel that needs to be produced.
Once dissolved the solution is then heated to facilitate liquid absorption and gelling by the hydrocolloid. A temperature between 85°C / 185°F and 95°C / 203°F will start the dissolution process. Gelling will begin upon cooling around 10°C / 50°F and 80°C / 176°F.
Gellan gum creates a non-thermoreversible gel and can withstand high heat without becoming reversed in form. This makes it ideal for the creation of warm gels.
Concentration Range: 0.2-1.0% for most applications. Twice as viscous as Agar at equal concentrations.
Dispersion: Gellan gum will disperse in cold water, but dispersion is aided by the use of warm to hot water, sugar, alcohol, or glycerin.
Hydration: Happens at around 194°F/90°C. Can be hydrated at low pH, around 3.0 or 4.0, which is unique amongst hydrocolloids.
Setting: Sets rapidly at relatively warm temperatures (see above for exact numbers).
Special uses: Spherification
Low-acyl Gellan Gum can be used instead of sodium alginate for spherification and reverse spherification due to its sensitivity to calcium ions.
Related post: How can i use gellan gum in cooking?
