What is E402?
Potassium alginate (E402) is a seaweed-derived thickener and stabiliser used in specified food applications. Goodnessly rates E402 Safe, while food-category permissions and regulator conditions still apply.
A seaweed-derived thickener and stabiliser used in specified food applications. Check the food category, amount and full formulation rather than judging one ingredient in isolation.
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Read the FAQ →
What is Potassium alginate?
Potassium alginate is a seaweed-derived thickener and stabiliser used in specified food applications. Its function depends on the formulation and the conditions attached to the permitted use.
What's it used for?
- Thickening a food formulation
- Helping stabilise a mixture
- Supporting texture in gels and other permitted foods
- Working at the maximum levels and conditions that apply
Where you'll find E402 on the shelf
You may see E402 in packaged foods where its technical function is useful and the food category permits it.
Is E402 permitted? What the regulators say
Potassium alginate is listed or permitted in the checked AU/NZ, EU and US frameworks with conditions. Permission is conditional: category, level, identity and specifications matter.
| Region | Status | What this means |
|---|---|---|
| AU/NZ Australia & New Zealand (FSANZ) | Permitted with conditions | FSANZ lists the additive number in its food-additive materials; the permitted use, food category and conditions are set by the Food Standards Code. [FSANZ source] |
| EU European Union (EUR-Lex) | Authorised with conditions | The consolidated Union list includes the additive for specified categories and conditions. [EUR-Lex source] |
| US United States (FDA) | Permitted with conditions | 21 CFR 184.1610 affirms potassium alginate for specified direct-food uses, with food categories, maximum levels and functional uses set out in the section. [FDA source] |
Goodnessly rates E402 Safe within its rating system. The rating does not remove the need to consider the product category, amount or full formulation.
- The FDA section specifies different maximum levels by food category, so “permitted” does not mean unrestricted use.
- The current sources checked for this draft do not state a new numerical ADI for this specific additive.
- Regulatory permissions can change; confirm the primary source when a product or use is unusual.
This section is checked periodically rather than continuously — confirm the current primary source before relying on a regulatory detail.
Who might want to limit or avoid it
- People comparing additive functions across products
- People checking the frequency of this ingredient in their usual foods
- People who want to consider the whole formulation and serving pattern
Goodnessly rates E402 Safe as a practical prompt to understand the ingredient, the product and the overall formulation.
How to spot it on a label
Look for:
- Potassium alginate
- 402
- E402
- Additive class (402)
Ingredient labels may use the name, the number, or the additive class followed by the number.
Related additives
Frequently asked questions
What is E402?
E402 is Potassium alginate, a seaweed-derived thickener and stabiliser used in specified food applications.
Is E402 permitted?
E402 is listed or permitted with conditions in Australia/New Zealand, the EU and the US sources checked for this draft.
What should I know about Potassium alginate?
No numerical ADI for this specific additive was stated in the current primary sources checked for this draft.
How does Goodnessly rate E402?
Goodnessly rates E402 (Potassium alginate) as Safe within its rating system.
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