Gellan Gum

What is Gellan Gum?

Gellan gum is a water soluble anionic hydrocolloid produced by the microorganism Sphingomonas elodea. This microorganism was discovered in 1978 in the United States by scientists at Merck following a concerted effort to find naturally occurring hydrocolloids.

Gellan gum is supplied as a free-flowing white powder. For commercial grades, gellan gum is manufactured by fermentation of a carbohydrate. In its native state, Gellan gum has acyl groups in its structure. Treatment with alkali removes acyl groups completely

Physicochemical Properties of Gellan Gum

Chemical Structure

Gellan gum is a straight chain polymer consisting of D-glucose, L-rhamnose and D-glucuronic acid units. In its native or high acyl grade, acetate and glycerate substituents are present on one of the glucose residues. The low acyl grade there is no acyl substituents. Note that the presence of acyl groups has a strong bearing on gel properties of Gellan gum.
Gellan Gum

Differences between High Acyl and Low Acyl Gellan Gum

  High Acyl Gellan Gum (KELCOGEL® LT100 Low Acyl Gellan Gum
Molecular weight 1 – 2 x106 Daltons 2 – 3 x105 Daltons
Solubility Hot water Cold or hot water
Set Temperature (oC) 70 – 80 30 – 50
Thermoreversibility Thermoreversible Heat stable

Where can you use Gellan gum?

Gellan gum is a useful and effective gelling agent in pharmaceutical and food products. It offers the following benefits:

  • It is effective at low concentrations
  • Provides a wide range of viscosities and textures
  • Gels on cooling
  • Forms fluid gels, which are solutions with a weak gel structure. These systems are extremely versatile for suspending drug substances without settling
  • Can be used in combination with other hydrocolloids

Uses of Gellan gum in pharmaceutical products

Application Typical products
Oral suspensions (immediate and sustained release) Ibuprofen, Paracetamol, Cetirizine
In-situ forming gels Nasal and ophthalmic products
Medicated gummies Vitamins and children medicines
Hair care products Stabilization of medicated shampoo formulations
Topical products Creams and lotions as a substitute for paraffins
Tablet coatings To improve slip and enhance swallowing
Oral care In toothpaste formulations to bind actives while creating a gel-like texture

Regulatory status

Approved for use in foods in Europe, USA, Japan, China and India. Gellan gum is also approved for use in non-food, cosmetics and pharmaceutical formulations in the USA, Canada, Australia, Brazil and China. Pharmaceutical use in EU falls under E418 (Directive EC/95/2). Gellan gum is manufactured in accordance with applicable food GMPs and complies with purity criteria defined in the current USP-NF monograph.


KELCOGEL® Gellan gum book, 5th Edition, CP Kelco, San Diego, USA

Mahdi M H et al., 2014. Evaluation of Gellan gum fluid gels as modified reléase oral liquids. International Journal of Pharmaceutics, 475; 335 – 343.

Kubo W et al., 2003. Oral sustained delivery of paracetamol from in-situ gelling Gellan and sodium alginate formulations. International Journal of Pharmaceutics, 258 (1-2); 335 – 343; 55-64