E424 - Curdlan

At a glance

• E-number: E424; functional classes: stabiliser and thickener
• Source: produced by microbial fermentation, then purified and dried
• Not sweet, not salty, and nearly tasteless; works mainly on texture
• Heat-stable gels that help products keep shape through cooking and freezing
• Common in noodles, processed meats, fillings, desserts, and dairy or meat alternatives

Why is Curdlan added to food?

Food makers use curdlan to control texture. It can make firm, elastic gels that hold water and keep products from breaking apart. Unlike many gums, curdlan’s gel stays stable during cooking and reheating, which helps foods keep their structure in hot soups, baked items, and fried or grilled products.¹ It also improves freeze–thaw stability, so foods do not weep or turn mushy after freezing.¹

What foods contain Curdlan?

You may find curdlan in:

• Asian‑style noodles and dumpling wrappers
• Processed meat and seafood (for sliceability and juiciness)
• Plant‑based meat and seafood alternatives
• Filled buns, pie fillings, and sauces
• Dairy analogues, puddings, and gelled desserts

In the European Union, curdlan (E424) is an authorised additive in specific food categories with conditions and limits set in the food additives legislation.² Its identity and purity requirements are defined in the EU additive specifications.¹

What can replace Curdlan?

Several hydrocolloids can play similar roles, depending on the texture and processing needs:

• For body and pourable thickness: xanthan gum, guar gum, or locust bean gum
• For firm, cuttable gels: agar or carrageenan
• For heat‑stable, brittle-to-elastic gels in beverages and gels: gellan gum
• For fruit‑based systems: pectins

Each behaves differently with salt, sugar, acid, and heat, so formulators often test blends to match curdlan’s unique, heat‑stable texture.

How is Curdlan made?

Curdlan is a high‑molecular‑weight beta‑1,3‑glucan (a chain of glucose units) produced by fermenting approved microorganisms under controlled conditions.¹³ After fermentation, the insoluble polymer is separated, purified, neutralised, washed, and dried to a fine powder that meets identity and purity specifications set by regulators.¹

Is Curdlan safe to eat?

EU authorities have evaluated curdlan as a food additive and allow its use within defined food categories and limits.² Specifications in EU law set purity criteria, including residuals and microbiological standards, to help ensure safety and consistent quality.¹ Internationally, Codex Alimentarius recognises curdlan (INS 424) as a food additive with thickening and stabilising functions, supporting its use across a range of foods following good manufacturing practice.³

Does Curdlan have any benefits?

• Texture that lasts: Curdlan forms firm gels that stay stable through heating, cooling, and many freeze–thaw cycles.¹
• Moisture management: It helps retain water, which can reduce syneresis (weeping) in fillings and gels.¹
• Neutral profile: It is essentially tasteless and colorless, so it does not change flavor or appearance.

Who should avoid Curdlan?

• People with sensitive digestion may experience gas or discomfort from large amounts of any poorly digestible polysaccharide.
• Anyone advised by a healthcare professional to limit certain thickeners or fiber‑like ingredients should check labels.
• As with any powdered ingredient, workers handling curdlan powder should avoid inhaling dust during manufacturing (a workplace, not consumer, concern).¹

Myths & facts

• Myth: “Curdlan is synthetic.” Fact: It is produced by microbial fermentation and then purified, similar to many other food gums.¹
• Myth: “Curdlan is the same as gluten.” Fact: Curdlan is a beta‑glucan carbohydrate, not a protein. It is unrelated to gluten.
• Myth: “Curdlan adds sweetness.” Fact: It has no meaningful sweetness; it is used for texture, not taste.
• Myth: “All gums melt when cooked.” Fact: Curdlan’s gels are notably heat‑stable, which is a key reason manufacturers use it.¹

Curdlan in branded foods

On ingredient lists, look for “curdlan” or “E424” (in the EU). It most often appears in noodles, dumplings, plant‑based meats, processed meats, and gelled desserts. Because label laws require listing additives by name, checking the ingredients panel is the easiest way to spot it.

References

Footnotes

1. Commission Regulation (EU) No 231/2012 — Specifications for food additives. EUR-Lex. https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹

2. Regulation (EC) No 1333/2008 on food additives. EUR-Lex. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32008R1333 ↩ ↩²

3. Curdlan (INS 424) — Codex GSFA (Food Additives) database. Codex Alimentarius (FAO/WHO). https://www.fao.org/gsfaonline/additives/en/ ↩ ↩²