What is E337?
A double salt of tartaric acid used for acidity and formulation functions where permitted. Goodnessly rates E337 Safe, while food-category permissions and regulator conditions still apply.
A double salt of tartaric acid used for acidity and formulation functions where permitted. 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 sodium tartrate?
A double salt of tartaric acid used for acidity and formulation functions where permitted. Its function depends on the formulation and the conditions attached to the permitted use.
What's it used for?
- Supporting acidity control
- Helping maintain formulation conditions
- Contributing to a consistent texture or stability
- Serving a permitted emulsifying or pH-control function
Where you'll find E337 on the shelf
You may see E337 in packaged foods where its technical function is useful and the food category permits it.
Is E337 permitted? What the regulators say
Potassium sodium tartrate is listed in the checked AU/NZ and EU frameworks with conditions, and the US source gives a specified food-use pathway. Permission is conditional: category, level, identity and specifications matter.
| Region | Status | What this means |
|---|---|---|
| AU/NZ Australia & New Zealand (FSANZ) | Permitted with conditions | FSANZ Schedule 15 lists potassium sodium tartrate for specified categories and conditions. [FSANZ source] |
| EU European Union (EUR-Lex) | Authorised with conditions | The consolidated Union list includes E337 for specified categories and conditions of use. [EUR-Lex source] |
| US United States (FDA) | Permitted with conditions | FDA 21 CFR §184.1804 affirms sodium potassium tartrate for food use under current good manufacturing practice. [FDA source] |
Goodnessly rates E337 Safe within its rating system. The rating does not remove the need to consider the product category, amount or full formulation.
- JECFA’s group ADI is 0–30 mg/kg body weight/day expressed as L(+)-tartaric acid.
- EFSA records checked for tartaric acid and tartrates described the re-evaluation as pending additional information; no completed newer opinion was identified.
- The current EU Union list and FDA provision for sodium potassium tartrate were checked.
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 E337 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 sodium tartrate
- 337
- E337
- Additive class (337)
Ingredient labels may use the name, the number, or the additive class followed by the number.
Related additives
Frequently asked questions
What is E337?
E337 is Potassium sodium tartrate, a double salt of tartaric acid used for acidity and formulation functions where permitted.
Is E337 permitted?
E337 is listed with conditions in Australia/New Zealand and the EU, and the FDA source gives a specified US food-use pathway.
What should I know about potassium sodium tartrate?
Use depends on the food category, amount, identity and the applicable regulator conditions; a listing is not a blanket permission for every food.
How does Goodnessly rate E337?
Goodnessly rates E337 (Potassium sodium tartrate) as Safe within its rating system.
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