Tartaric acid
A naturally occurring fruit acid, most abundant in grapes, used in food and drink to add sharpness and stabilise acidity.
EFSA established a group ADI of 240 mg/kg body weight per day (as tartaric acid) for E334 to E337 and E354, raising it from the 1990 figure of 30 mg/kg; no toxic or genotoxic effects were found.
What is it?
Tartaric acid is a dicarboxylic organic acid found naturally in many fruits, most abundantly in grapes, tamarinds, and bananas. Commercially it is recovered as a by-product of wine production, where it precipitates as cream of tartar (potassium hydrogen tartrate) on the inside of fermentation tanks. The food-grade form used as E334 is predominantly the naturally occurring L-(+)-tartaric acid enantiomer.
What does it do?
As an acidity regulator it lowers and stabilises pH in food and drink, which inhibits microbial growth and enzymatic browning, and improves the stability of other additives such as antioxidants. Its sharp, clean sourness also functions as a flavouring. In bakery products it reacts with sodium bicarbonate as a leavening acid. In confectionery it provides the sharp 'bite' of sour sweets.
Where you will see it
Found in wine and grape juice (where it occurs naturally and may also be added), sour sweets and confectionery, carbonated soft drinks, bakery powder and baking mixes, fruit preserves, jam and marmalade, and some canned fruits. On a UK label it appears as 'tartaric acid', 'E334', or within the ingredient 'cream of tartar' (E336).
What the science says
Metabolism and kidney stone risk
Tartaric acid is absorbed in the small intestine and excreted mainly unchanged in the urine. At very high doses in animal studies, urinary tartrate crystals can contribute to renal tubular damage, but intakes from food are orders of magnitude below those levels. There is no established link between normal dietary exposure to E334 and kidney stone formation in humans.
EFSA's Panel on Food Additives and Nutrient Sources (ANS) reviewed tartaric acid and its salts (E334-E337) and concluded that the available data did not raise a safety concern at typical food-additive use levels.
In animal studies, very high oral doses of tartaric acid caused nephrotoxicity (renal tubular crystallisation), but no toxicologically relevant effects were observed at doses relevant to food use.
ADI and typical dietary exposure
EFSA set no numerical acceptable daily intake for tartaric acid, reflecting that at realistic food intakes no adverse effects have been demonstrated. The body handles tartaric acid as a normal organic acid and most of it passes through unmetabolised.
No numerical ADI was established for E334; EFSA considered exposure from permitted uses to be of no safety concern.
Where it stands with the regulators
Who should be careful
No specific population is required to avoid tartaric acid at food-use levels. People with a history of kidney stones may wish to be aware that tartrate is excreted in urine, though there is no established link between food-level exposure and stone formation. Anyone concerned should discuss their diet with a doctor.
The honest read
Tartaric acid is one of the most ordinary organic acids in food: it is the predominant acid in grapes and has been extracted from wine-making by-products for centuries. EFSA reviewed it in 2010 and found nothing warranting a numerical limit. The only noted toxicological effect, kidney damage in rodents, required doses far above anything achievable through food. There is no active scientific debate about it at food-use levels.
Related additives
Common questions
Is E334 banned in the UK?
No. Tartaric acid is approved for use in food and drink in the UK under the assimilated EU Regulation 1333/2008 and remains on the UK FSA approved-additives list.
Is E334 the same as cream of tartar?
They are related but different. Tartaric acid (E334) is the free acid. Cream of tartar is potassium hydrogen tartrate (E336), the potassium salt of tartaric acid. Both come from the same source, tartaric acid naturally present in grapes and wine, and both are permitted food additives.
What foods contain E334?
E334 is most commonly found in sour sweets and confectionery, carbonated soft drinks, wine, grape juice, baking powders, fruit preserves and some canned fruit products. On the label it appears as 'tartaric acid' or 'E334'.
Is E334 vegan?
Yes. Commercially produced tartaric acid is recovered from wine-making by-products (grape skins and fermentation sediment), making it plant-derived and suitable for vegans. Some strict vegans avoid it when listed alongside wine-derived ingredients, but the acid itself contains no animal products.
Sources
- EFSA ANS Panel: Re-evaluation of tartaric acid (E334), sodium tartrates (E335), potassium tartrates (E336), potassium sodium tartrate (E337) and calcium tartrate (E354) as food additives
- UK FSA: Approved additives and E numbers
- EU Regulation 1333/2008 on food additives (Annex II)
See this on every food you scan
NutraSafe reads the label and puts every additive into plain English, with the source, right in the app.
Get NutraSafe on the App Store