E336 – Potassium tartrates | cream of tartar safety, uses and side effects

Quick analysis summary about E336 – Potassium tartrates food additive

Bottom line about E336

E336 covers potassium tartrates, mainly monopotassium tartrate (E336(i)) and dipotassium tartrate (E336(ii)). At normal food-use levels, the overall evidence is reassuring enough for a GREEN – SAFE rating.[1-4]

Why this grade for E336

Recent re-evaluations did not find a relevant genotoxic or carcinogenic signal for tartaric acid and its sodium and potassium salts, and the main long-term rat studies did not show harmful effects at high tested doses.[1-4] The main caution is not ordinary food use, but unusually large intake of potassium bitartrate such as cream of tartar taken as a home remedy or purge.[5]

Who may want to limit or avoid E336

Most people do not need to avoid E336 in ordinary foods. People with advanced kidney disease, people advised to restrict potassium, and anyone using large non-food amounts of cream of tartar should be more careful.[5]

Common uses and where E336 appears

E336 is used as an acidity regulator, stabiliser, and processing aid. It can appear in baking powders, confectionery, jams, fruit and vegetable products, table-top sweeteners, and some wine-related processing uses.[1,6]

E336 source or origin

Potassium tartrates are salts of tartaric acid. Monopotassium tartrate is also known as cream of tartar and is commonly obtained during winemaking, then purified for food use.[6,7]

Intake note for E336

EFSA set a group ADI (Acceptable Daily Intake) of 240 mg/kg body weight per day, expressed as tartaric acid, for tartaric acid and tartrates including E336.[1] For a 60 kg adult, that is 14,400 mg per day expressed as tartaric acid. This is a relatively high benchmark, which supports the view that normal dietary exposure is usually not a major concern.[1]

Is E336 banned anywhere?

In the EU, E336 remains authorised for specified food uses, and in the US monopotassium tartrate is affirmed as GRAS (Generally Recognized as Safe) for direct food use under current good manufacturing practice.[6,7] No clear major food-use ban was identified in the reviewed jurisdictions, and Japan has also carried out a positive safety assessment for dipotassium L-tartrate.[4]

Safety grading GREEN – SAFE

E336 is graded GREEN – SAFE because the overall toxicology record is broadly reassuring at realistic food-use levels. Major reviews did not identify a meaningful genotoxicity concern, long-term animal data did not show carcinogenicity at high tested doses, and ordinary dietary exposure is generally well below health-based guidance values.[1-4] The main practical caution is excessive non-standard intake, especially of cream of tartar, which can deliver a large potassium load and cause problems that do not reflect normal additive use.[5]

Study basis or key toxicological reasoning for E336

EFSA’s 2020 re-evaluation of tartaric acid and tartrates established a group ADI of 240 mg/kg bw/day as tartaric acid and found no indication of genotoxicity for tartaric acid and its sodium and potassium salts.[1] The key chronic rat study on monosodium L(+)-tartrate found no carcinogenicity at the highest tested dose of 3,100 mg/kg bw/day, approximately 2,440 mg/kg bw/day expressed as tartaric acid, and this reference point was central to later risk assessments.[1,2] JECFA had already assigned an ADI of 0-30 mg/kg bw/day expressed as L(+)-tartaric acid decades earlier, reflecting a long-standing low-concern view.[3] A newer Food Safety Commission of Japan assessment for dipotassium L-tartrate also identified a NOAEL (No Observed Adverse Effect Level) of 2,440 mg/kg bw/day as tartaric acid and concluded that appropriately used food-additive exposure did not raise safety concerns.[4] The main caveat is that very large intakes of potassium bitartrate outside normal food use have caused life-threatening hyperkalaemia in case reports, so the reassuring grade does not apply to deliberate high-dose ingestion.[5]

Side effects of E336 – Potassium tartrates food additive

Usually no obvious problem at normal intake: ordinary food amounts are generally well tolerated.[1-4]
Possible stomach upset at high intake: very large amounts of tartrate salts can cause nausea, vomiting, abdominal discomfort, or diarrhoea.[1,3]
Potassium overload is the main special risk: unusually large intakes of cream of tartar can push blood potassium dangerously high.[5]
Extra caution in kidney disease: people who already struggle to control potassium may be less able to handle excessive intake.[5]

Should You Avoid E336 – Potassium tartrates food additive?

For most people, E336 does not need special avoidance in ordinary foods. A more cautious approach makes sense for people with kidney disease, people on potassium-sparing medicines, or anyone using cream of tartar in unusually large homemade doses rather than as a small food ingredient.[5]

Common uses of E336 – Potassium tartrates food additive

Baking powders and bakery mixes as an acid component
Confectionery and sugar work to help control crystallisation
Jams, jellies, and fruit-based products as acidity regulators
Wine-related processing and stabilisation uses
Some table-top sweeteners and preserved fruit or vegetable products in the EU[6]

Common names and synonyms of E336 – Potassium tartrates food additive

Potassium tartrates
Monopotassium tartrate
Dipotassium tartrate
Potassium hydrogen tartrate
Potassium bitartrate
Cream of tartar
E336
E336(i)
E336(ii)
INS 336

What is E336 – Potassium tartrates food additive?

E336 is the food-additive group name for potassium tartrates. In practice, this mainly means monopotassium tartrate, better known as cream of tartar, and dipotassium tartrate. These ingredients are salts of tartaric acid, a naturally occurring acid associated especially with grapes and winemaking.

In foods, potassium tartrates are used mainly to regulate acidity, support texture or stability, and help certain processing functions. In baking, cream of tartar is especially familiar because it reacts with bicarbonate to release carbon dioxide and improve rise. Safety assessments treat these substances largely through their shared tartaric-acid toxicology, and the available evidence does not suggest that ordinary dietary exposure creates a major toxicological concern.[1-4]

Where is E336 – Potassium tartrates food additive allowed (EU vs US)?

In the EU, E336 potassium tartrates remain authorised for specified food categories under the Union additives framework. In the US, monopotassium tartrate is affirmed as GRAS under 21 CFR 184.1077 for direct food use in line with good manufacturing practice, although US labelling usually uses chemical names rather than the EU E-number system.[6,7]

E336 – Potassium tartrates