What is E337?

E337 (Sodium potassium tartrate) is a antioxidants food additive. Rochelle salt, acidity regulator. E337 sits in the E300–E399 series, which in the EU classification mainly covers antioxidants and acidity regulators.

What is E337 used for?

E337 belongs to the antioxidants group. Antioxidants stop fats going rancid and food discolouring. Several are natural, such as ascorbic acid (vitamin C).

Is E337 safe?

E337 is considered safe at the levels used in food and is approved for use in the EU. “Safe” means it is approved in the EU and regarded as safe at the levels used in food.

How E337 appears on labels

On food packaging you'll find E337 either as the number “E337” or by the name “Sodium potassium tartrate” in the ingredient list, often after its function. Ingredients are listed in descending order by weight, so an additive near the end is present only in small amounts.

Is E337 vegan?

Yes, E337 is suitable for vegans.