The Gellan Gum Technical Handbook

1.1 What Is Gellan Gum

Gellan gum is a high molecular weight anionic exopolysaccharide produced by microbial fermentation — the most prominent microbial hydrocolloid after xanthan gum. It is made by pure-culture aerobic fermentation of Sphingomonas elodea (formerly Pseudomonas elodea, ATCC 31461) on a carbohydrate carbon source, followed by precipitation with an organic solvent, dewatering, drying, milling and sieving.

If you remember only three things, remember these — they explain why the industry reaches for gellan gum rather than cheaper xanthan or carrageenan in beverage suspension, clear jellies and plant-based dairy:

1.2 Discovery and Commercialization

The commercialization path is instructive: it landed in Japan first, then achieved food-safety recognition in the US and Europe, and was finally harmonized through Codex and national standards. Understanding that sequence helps you anticipate compliance expectations in different markets.

1.3 Manufacturing and Critical Control Points

The process route determines batch-to-batch consistency. With the same strain and the same fermentation conditions, the degree of downstream alkali treatment alone decides whether you obtain high acyl or low acyl product — which is why this is one of the first things to confirm with a supplier.

1.4 Product Classification and Grades

Gellan gum has two independent classification axes: by acyl content (which determines function) and by purity and end use (which determines regulation and price). State both when requesting a quotation, otherwise it is easy to receive the right type at the wrong grade.

By acyl content

By purity and grade

1.5 Product Identification at a Glance

2.1 The Tetrasaccharide Repeating Unit

The gellan backbone is a linear, unbranched anionic polysaccharide built from a tetrasaccharide repeating unit. Understand that unit and you understand why the chain is rigid, why it carries a negative charge and why calcium can crosslink it.

• Glucuronic acid provides the only functional carboxyl group — one negative charge per tetrasaccharide unit. This is why divalent cations can crosslink it.
• Rhamnose introduces twist and rigidity — the backbone is not a flexible random coil but an approximately ribbon-like chain, which is why it forms an effective gel network at very low concentration.
• The carboxyl groups exist naturally as mixed salts — they are neutralized by K⁺, Na⁺, Ca²⁺ and Mg²⁺. The actual composition depends on the fermentation medium and downstream process, which is the fundamental reason gel strength varies naturally between batches.

2.2 Acyl Substitution: the HA / LA Divide

The native fermentation product is the high acyl (HA) form. Substitution takes place on the glucose residue adjacent to glucuronic acid — an L-glyceryl group at O-2 and an acetyl group at O-6. Substitution is not complete: on average there is about one glyceryl and about half an acetyl group per repeating unit. Industrial production removes these groups by alkaline hydrolysis to give low acyl (LA).

Blending the two is the industry's most-used trick: adjusting the LA : HA ratio gives a continuous texture spectrum between "firm and brittle" and "soft and springy", and can even approach the mouthfeel of carrageenan or gelatin. See Section 3.1.

2.3 Molecular Weight and Distribution

Figures circulating for molecular weight are inconsistent, because both the measurement method (viscometry vs GPC-MALLS) and the sample state (depolymerized or aggregated) vary enormously. Three reference values are given below — cite them according to your purpose:

2.4 Charge Properties and Ionic Forms

• Anionic polysaccharide: the charge comes from the glucuronic acid carboxyl group, with a pKa of about 3.5.
• Low charge density, very high efficiency: on average only one carboxyl group per tetrasaccharide unit — far lower than pectin. But because the chain is rigid and the double helix concentrates the charges, crosslinking efficiency per charge is very high.
• pH determines the charge state: above pH 3.5 the carboxyl groups dissociate and carry negative charge; interchain electrostatic repulsion stabilizes the solution. Below pH 3.5 they protonate, the molecules tend to aggregate, gel performance falls and clarity drops.
• Ionic strength is a double-edged sword: a moderate level of cations promotes gelation; an excess of monovalent ions (for example high NaCl) screens the charges, suppresses double-helix formation and weakens or even prevents gelation.

2.5 Molecular Mechanism of Gelation

Gelation is a three-stage physical process. Every step in a formulation process serves one of these three stages.

1. Hot hydration — random coilLow acyl gum must be heated to about 75–80 °C for complete hydration (high acyl, about 70–80 °C). The molecules disperse as random coils and the system is a low-viscosity solution. Note that at this point it is not viscous like xanthan gum.
2. Cooling — double helix formationAs temperature falls, chain segments associate into double helices. For low acyl gum this begins around 25 °C without added cations; for high acyl, around 65 °C.
3. Cation bridging — aggregation and network formationDivalent cations (Ca²⁺, Mg²⁺) form "egg-box" bridges between double helices using carboxyl groups as anchor points. The helices aggregate further into microfibrils and finally into a three-dimensional network. The amount of calcium and the timing of its addition directly determine gel strength.

3.1 Gelling Performance and Dosage Efficiency

Gellan gum's core competitive edge is doing the most precise gel with the least material. Low acyl gellan gum forms a fully structured gel at about 0.05% with sufficient calcium — an efficiency most natural hydrocolloids cannot approach.

The LA : HA blend ratio is the most direct way to tune texture, and can approach the mouthfeel of other hydrocolloids:

3.2 Suspension and Fluid Gels

This is the capability that made gellan gum famous in beverages, and what sets it apart from xanthan gum: suspension does not require high viscosity, only yield stress.

• Fluid gel: at dosages well below the gelling concentration (0.02%–0.15%), gellan gum forms an extremely weak network that has been broken up by shear. At rest this network has a yield stress high enough to hold cocoa powder, fruit pulp particles, calcium, protein and curcumin in suspension. Once pumping or filling imposes shear, the network breaks down, the system thins and flows normally.
• Shear thinning: exactly the rheology a beverage line needs — no sedimentation at rest, no blockage while flowing.
• Mouthfeel advantage: because it relies on a network rather than viscosity, the finished drink tastes clean rather than cloying, without the slimy, stringy sensation of high-dose xanthan gum.

3.3 Thermal Stability and Reversibility

Thermal behaviour is where LA and HA differ most dramatically, and where selection is easiest to get wrong — the same "low acyl" grade behaves completely differently in pure water and in milk.

3.4 pH Stability and Acid Tolerance

• Stable from pH 3 to 7. Within this range gel strength and clarity remain essentially constant and pH cycling causes no permanent damage.
• Below pH 3.5: carboxyl groups protonate, interchain electrostatic repulsion falls and the molecules aggregate — gel strength drops and clarity worsens, while acid hydrolysis at elevated temperature accelerates.
• Alkaline conditions (pH > 8) combined with prolonged high temperature also cause backbone degradation and irreversible loss of gel strength.

3.5 Clarity and Optical Performance

Low acyl gellan gels typically reach a light transmittance of over 85% (a common in-house specification), approaching glass-like clarity. This is not a decorative parameter — for many categories it is an entry requirement:

3.6 Synergy with Other Hydrocolloids

In a blend, gellan gum plays the role of scaffold: it provides a strong, heat-stable three-dimensional network with yield stress, while other hydrocolloids fill the interstices to supply viscosity, water-holding or elasticity. Once you see it that way, blending becomes intuitive.

3.7 Protein Compatibility and Dairy Systems

This is why gellan gum is hard to replace in dairy.

• No protein reactivity: between pH 4 and 7, gellan gum does not form electrostatic complexes or precipitates with casein or whey protein. This contrasts sharply with pectin and CMC, which require careful concentration control to avoid flocculation — so the formulation has far more tolerance.
• Weak gel network in milk: in milk systems gellan gum forms a weak gel network that delivers "suspension without thickening" — the long-term stability of cocoa milk, calcium-fortified milk and plant-based milk depends heavily on this.
• Whey separation control in fermented milk: in yoghurt and fermented milk, gellan gum effectively suppresses whey syneresis while giving a spoonable texture, improving the thin mouthfeel of low-fat products.
• Watch the calcium effect in milk: milk contains its own calcium, which additionally reinforces the gellan network, so dosages in milk systems are typically 20%–50% lower than in pure water. A dedicated gradient trial is required.

3.8 Flavor Release, Mouthfeel and Digestion

4.1 Product Matrix and Selection Criteria

Gellan gum grades are normally described along three dimensions: acyl type (LA / HA), performance level (gel strength, transmittance) and particle size (mesh). The table below gives the industry-standard product matrix. The exact grade names and measured values of each Cinogel product are stated in the CoA supplied with the goods.

4.2 Physicochemical Specifications

Mandatory requirements of the Chinese national standard

^a Applies only to gellan gum produced by non-ethanol processing (i.e. precipitated with isopropanol).

Identification tests

Common in-house specifications (industry reference values)

4.3 Microbiological Specifications

4.4 International Standard Comparison

The same batch shipped to different markets requires different compliance documentation. The table below highlights the differences between the four main systems so all documents can be prepared in one pass.

4.5 Packaging, Storage and Shelf Life

5.1 Beverages

Beverages are the fastest-growing and most technically demanding application for gellan gum. It solves exactly one core problem: keeping insoluble material suspended in a liquid for the long term, without making the drink viscous. Fruit pulp, cocoa powder, calcium, plant protein, curcumin — traditionally these could only be handled by thickening with xanthan gum, at the cost of a cloying, stringy mouthfeel.

Sub-segments and key points

5.2 Dairy Products

Dairy is where gellan gum's "no protein reactivity" advantage is most obvious. It does not need to tiptoe around the isoelectric point the way pectin or CMC do, so formulation tolerance is high; and the potassium naturally present in milk lets it form a weak gel that suspends without thickening.

5.3 Jellies and Gummy Confections

This is the textbook application of low acyl gellan gum and the most established route to replacing gelatin with a vegetarian formula. It satisfies three demanding requirements at once: high clarity, cuttability and heat resistance.

5.4 Bakery and Fillings

Bakery is where low acyl gellan gum's heat resistance is used most thoroughly: an ordinary gel would have melted long before it left the oven, while an LA gel formed with calcium keeps its shape at baking temperatures.

5.5 Jams, Sauces and Seasonings

• Jams / fruit purées: LA provides structure, improving spreadability and reducing syneresis, with less damage to fruit flavour from prolonged boiling.
• Salad dressings / mayonnaise: gellan gum supplies yield stress, stabilizing the oil-water emulsion and preventing oil separation; in low-fat recipes it restores a full-bodied mouthfeel.
• Seasoning sauces / oyster sauce / gravy: resists syneresis and separation and stays uniform long after filling; blending with xanthan gum delivers both thickness and body.
• Syrups / dessert toppings: suspends fruit pieces and nut fragments and prevents settling.

5.6 Meat and Seafood Products

• Reformed / restructured meat: LA plus calcium forms a heat-stable binding structure that holds together and slices cleanly after cooking.
• Sausages, meatballs, surimi products: improves water holding and elasticity, gives a denser cut surface and reduces cooking loss.
• Plant-based meat / analogue foods: blended with konjac gum it forms a boil-resistant, chewy fibrous structure — a common texture strategy for plant-based meat.
• Seafood products: improves surimi gel strength and water retention.

5.7 Pet Food

• Canned / wet pet food: LA with a calcium source forms a firm gel that suspends meat pieces evenly in the gravy, without collapsing or syneresis after 121 °C retorting.
• Meat strips / meat jelly: improves formability and cut appearance, making portioning and feeding easier.
• Liquid nutritional pastes: provides yield stress to prevent fat separation and layering.

5.8 Plant Tissue Culture and Microbiological Media

This is the highest-value, most technically demanding niche for gellan gum. As an agar replacement it leads on four fronts: clarity, batch consistency, dosage efficiency and autoclave tolerance.

• Plant micropropagation: orchids, banana, potato, strawberry, blueberry and more — the transparent gel makes root and tissue development easy to observe microscopically and contamination easy to spot early.
• Thermophilic microorganism culture: the gel is thermally stable enough to survive long high-temperature incubation without liquefying.
• Microbial plate counting: colonies spread less (smaller spreader colonies), making counting easier.

5.9 Pharmaceuticals and Excipients

5.10 Personal Care and Oral Care

• Clear gels and masks: crystal-clear appearance and a clean, non-tacky skin feel, suitable for serum gels, masks and eye patches.
• Lotions and creams: thickens and stabilizes the emulsion, improving spreadability and richness.
• Shampoo and hair care: suspends pearlescent agents, silicones and anti-dandruff actives, preventing settling and separation.
• Toothpaste: thickening and structural stability, with good compatibility in high-electrolyte systems — something many natural hydrocolloids struggle with.
• Antiperspirants and solid balms: provides structural strength and a pleasant application feel.

5.11 Industrial and Other Applications

Most gellan gum failures are not caused by choosing the wrong grade but by getting the process wrong. The table below lists the four most frequent problems in the industry; each is broken down in turn.

6.1 Dispersion: Avoiding Lumps

On contact with water the outer layer of gellan gum hydrates and swells rapidly, encapsulating the dry powder inside and forming what the industry calls a "fish eye". Once formed, no amount of subsequent heating or agitation will fully dissolve it, causing a direct loss of gel strength and clarity.

6.2 Hydration: the Temperature Window

Incomplete hydration is the standard explanation for "the gel strength is only half of what it should be". Unlike xanthan gum, gellan gum does not swell in cold water — it has a hard temperature requirement.

6.3 Ion Control: the Decisive Step

If a customer remembers only one operational point from this handbook, it should be this: for low acyl gellan gum, how much calcium and how fast it is released determine gel strength and uniformity.

Gel-promoting power of cations

Choosing a calcium source: release rate matters more than content

Choosing an ion strategy by objective

6.4 Shear, Cooling and Setting

6.5 Typical Formulation Examples

The five examples below are starting formulas. Run a bench trial with the stated process and optimize by gradient before scaling up. All percentages are by weight.

Example 1　Clear jelly (LA system)

1. Dry blendDry-blend the gellan gum with part of the sugar at 1:8.
2. HydrateAdd to 85 °C water and agitate at high shear for 8 min until fully clear.
3. Add ionsAdd sodium citrate and calcium lactate and stir until dissolved.
4. Acidify and flavourCool to 70 °C, then add citric acid, flavour and colour.
5. Fill and setFill into moulds and hold at room temperature for at least 4 h to set.

Example 2　Neutral plant protein drink (suspension type)

1. Dry blendDry-blend the gellan gum with sugar, then pre-disperse into 60 °C water under agitation.
2. HydrateHeat to 80–85 °C and hold 10 min until fully hydrated.
3. Add ingredientsAdd the base, calcium source and sodium bicarbonate; adjust pH to about 7.0.
4. Homogenize and sterilizeHomogenize, then UHT sterilize (e.g. 137 °C / 4 s).
5. FillFill above the setting temperature; the network forms as the package cools.

Example 3　Vegetarian gummy confectionery (LA + HA blend)

1. Cook the syrupHeat syrup and water to 105–108 °C to about 78% solids.
2. HydrateAdd the pre-blended gellan gum (dry-blended with part of the sugar) and hold at 85–90 °C under high shear for 10 min.
3. Add ionsCool to 80 °C and add sodium citrate and calcium lactate.
4. Acidify and flavourAdd citric acid, flavour and colour, then deposit as quickly as possible.
5. Dry and setDeposit into starch moulds and dry at 40–50 °C for 24–48 h; polish after demoulding.

Example 4　Cocoa milk (milk suspension system)

1. PreheatHeat the milk to 75 °C.
2. HydrateAdd the gellan gum and carrageenan (dry-blended with sugar) and hold at 80–85 °C for 10 min.
3. Add ingredientsAdd cocoa powder, sugar and salt, dispersing thoroughly.
4. Homogenize and sterilizeHomogenize, then UHT sterilize.
5. Cool and fillCool to above the setting temperature and fill; the weak gel network forms in the package.

Example 5　Plant tissue culture medium (per 1 L)

1. DisperseAdd water and stir to disperse the gellan gum, avoiding lumps.
2. DissolveHeat to 90–95 °C and stir until completely clear.
3. Add ingredients and adjust pHAdd basal salts, sucrose and hormones; adjust pH to 5.7–5.8.
4. Dispense and sterilizeDispense and autoclave at 121 °C for 15–20 min.
5. Pour platesCool to about 60–70 °C and mix well before pouring (re-mixing after sterilization is essential, otherwise the gel will be uneven).

6.6 Troubleshooting Manual

The table below can be printed and pinned up in the batching area. Work through "symptom → cause → action" to locate the vast majority of real-world gellan gum problems.

7.1 China

Basis for use: GB 2760-2024

• Standard title: National Food Safety Standard — Standard for the Use of Food Additives, GB 2760-2024, effective 8 February 2025.
• Basic identifiers: CNS number 20.027, INS number 418, functional class thickener.
• Permitted use: gellan gum is an additive permitted at levels consistent with Good Manufacturing Practice and may be used in the great majority of food categories; the exceptions listed in Table A.2 of GB 2760-2024 may not be used.
• On 5 February 2026, China's National Health Commission issued Announcement No. 1 of 2026 (on 22 "three-new foods" including gardenia oil), which approved an extension of gellan gum use to cream (food category 01.05.01) to improve sensory quality.

Quality standard: GB 25535-2010

• Standard title: National Food Safety Standard — Food Additive: Gellan Gum, issued 21 December 2010, effective 21 February 2011.
• Applies to the food additive gellan gum produced by pure-culture fermentation of carbohydrates with Pseudomonas elodea followed by processing.
• A revision was launched by the national standards authority in 2024 (project spaq-2024-12). Planned changes include refining the scope and molecular structure description, improving the isopropanol test method, adding a lead test method, deleting the relative molecular mass requirement, and adding a description of commercial product classification.

Typical applications and food category numbers (engineering reference)

7.2 United States

• Legal basis: the US Food and Drug Administration approved gellan gum as a food additive in 1992, listed at 21 CFR 172.665 Gellan Gum.
• Principle of use: as a direct food ingredient, used at the lowest level consistent with good manufacturing practice (cGMP) to achieve the intended technical effect.
• Quality specification: follows FCC (Food Chemicals Codex) requirements, essentially harmonized with the JECFA specification.
• Scope: broad, covering beverages, dairy, confectionery, bakery, sauces and other major categories.
• Labelling: declared in the ingredient list as Gellan Gum.

7.3 European Union

• Code: E418.
• Legal basis: listed in Annexes II / III of Regulation (EC) No 1333/2008 on food additives, used according to the specified food categories and levels.
• Quality specification: Commission Regulation (EU) No 231/2012, essentially consistent with JECFA. The differences are that the EU additionally sets limits for arsenic (≤3 mg/kg), mercury (≤1 mg/kg) and cadmium (≤1 mg/kg), and specifies Escherichia coli (negative in 5 g) and Salmonella spp. (negative in 10 g).
• Labelling: may be declared as Gellan gum or E418.

7.4 Other Major Markets

7.5 Safety and Acceptable Daily Intake

An ADI of "Not Specified" is the highest classification in food additive safety evaluation — it means that, on the available toxicological data, no numerical daily intake limit is needed for safe use. This conclusion is endorsed by the Codex Alimentarius Commission, the US FDA, the European Commission, Japan's MHLW and FSANZ.

• Not digested or absorbed: as a microbial polysaccharide, gellan gum passes through the human gastrointestinal tract essentially unchanged and is excreted, placing it in the soluble dietary fibre category.
• No known allergenicity: as a fermentation polysaccharide it contains none of the common food allergen proteins.
• Vegetarian friendly: produced by microbial fermentation, fundamentally different from gelatin (animal-derived); suitable for vegetarian and vegan products.

7.6 Certification and Labeling

8.1 Hazards and Occupational Protection

Gellan gum is itself a food-grade material with very high oral safety. At plant level the main occupational risk comes from dust — but the most frequent accidents are not respiratory, they are slipping on wet floors.

8.2 Storage Conditions and Stability

Main degradation mechanisms

• Hydrolytic degradation: high temperature plus high humidity plus acidic conditions cause backbone hydrolysis, leading to lower molecular weight and permanent, irreversible loss of gel strength.
• Moisture pickup and caking: absorbed moisture partially hydrates the particle surfaces, which appears macroscopically as caking and reduces dissolution performance.
• Microbial contamination: poor sealing combined with high humidity can allow microorganisms to grow, jeopardizing microbiological compliance.

8.3 Packaging and Transport

8.4 Quality Assurance and Traceability

Food additive buyers — especially multinational food companies — usually have strict supplier qualification requirements. Having the following documents ready in one package can significantly shorten a customer's audit and onboarding cycle.

Appendix A　Selection Decision Tree

Answer the following four questions in order to locate the recommended grade. The sequence cannot be reversed — the first question sets the direction; the remaining three only fine-tune it.

Appendix B　Dosage Quick-Reference by Application

This table consolidates the recommended grades and dosages from Sections 5.1 to 5.11 as a formulation starting point. Every value must be validated by gradient trial in the actual system.

Appendix C　Comparison with Other Hydrocolloids

Appendix D　Summary of Test Methods

Appendix E　Glossary

Appendix F　Referenced Standards and Regulations