E351 - Potassium malate

At a glance

• What it is: a potassium salt of malic acid used as an acidity regulator and flavor enhancer.
• What it does: sets and stabilizes pH, boosts sourness, and helps flavors stay stable over time.
• Where it’s found: flavored drinks, candies, fruit fillings, jams, and some bakery and dairy-style products.
• Label names: “potassium malate,” “E351,” or “acidity regulator.”

Why is Potassium malate added to food?

Manufacturers add potassium malate to adjust and control acidity (pH), which helps shape taste, texture, and shelf life. As an acidity regulator, it can make foods pleasantly tart while keeping the pH steady so flavors don’t drift as the product ages.¹ It is closely related to malic acid but is less sharp and can provide a smoother, longer-lasting sourness in some recipes.²

What foods contain Potassium malate?

You’ll mostly see potassium malate in:

• Flavored waters, juices, energy and sports drinks
• Hard candies, gummies, and chews
• Fruit fillings, jams, and dessert sauces
• Some bakery items and dairy-style desserts

On ingredient lists, it often appears as “potassium malate” or “E351,” sometimes grouped with other acidity regulators such as citric acid or sodium citrates.

What can replace Potassium malate?

Depending on the recipe and flavor target, formulators might use:

• Malic acid for a sharper sour profile
• Sodium malates or calcium malates when a different mineral salt is preferred
• Citric acid, potassium citrates, or phosphoric acid for alternative acidity regulation and buffering

Each option changes flavor, pH control, mineral content, and solubility, so swaps are recipe-specific.

How is Potassium malate made?

Food-grade potassium malate is produced by neutralizing malic acid with a potassium base, typically potassium hydroxide or potassium carbonate, then purifying and drying the salt.³ In EU law, it is defined and specified as the potassium salts of malic acid, with set purity criteria and identification tests.³

Is Potassium malate safe to eat?

In the European Union, malic acid (E 296) and its salts—including potassium malate (E 351)—were re‑evaluated by the European Food Safety Authority (EFSA). EFSA concluded there is no safety concern for their use at the reported levels and uses in foods.² Potassium malate is an authorized food additive under EU rules, with general definitions and conditions laid out in Regulation (EC) No 1333/2008.¹

Does Potassium malate have any benefits?

• Taste: It provides a clean, fruity tartness and can round out sweetness in drinks and candies.²
• Stability: As an acidity regulator, it helps keep pH steady, which supports flavor and product stability over shelf life.¹
• Minerals: It adds a small amount of potassium to the diet, though foods typically use it for function, not as a mineral supplement.

Who should avoid Potassium malate?

Most people don’t need to avoid E351. However:

• People who must limit potassium—such as some individuals with chronic kidney disease or those advised by their clinician to control potassium intake—should review labels for potassium-containing additives, including potassium malate.⁴
• If your healthcare provider has warned you about high potassium (hyperkalemia) or interactions with potassium-sparing medicines, ask whether you need to limit foods with potassium salts.⁴

Myths & facts

• “E-numbers are always synthetic.” False. E-numbers are just codes for approved additives in the EU; they include both naturally derived and synthetic ingredients.
• “Potassium malate is the same as malic acid.” Not exactly. It’s the potassium salt of malic acid, offering similar tartness but different pH behavior and solubility.
• “If a product has E351, it’s unsafe.” False. EFSA has re‑evaluated malic acid and its malate salts and found no safety concern at reported uses and levels.²

Potassium malate in branded foods

On labels, look for “potassium malate,” “E351,” or “acidity regulator.” You’re most likely to find it in flavored beverages, sour candies, fruit spreads and fillings, and some shelf‑stable desserts. It often appears alongside other acidulants like citric acid or buffers such as sodium citrates.

References

Footnotes

1. Regulation (EC) No 1333/2008 on food additives (definitions and conditions of use) — Official Journal of the European Union. https://eur-lex.europa.eu/eli/reg/2008/1333/oj ↩ ↩² ↩³

2. Re-evaluation of malic acid (E 296), sodium malate (E 350), potassium malate (E 351) and calcium malate (E 352) as food additives — European Food Safety Authority (EFSA). https://www.efsa.europa.eu/en/efsajournal/pub/5142 ↩ ↩² ↩³ ↩⁴

3. Commission Regulation (EU) No 231/2012 laying down specifications for food additives listed in Annexes II and III to Regulation (EC) No 1333/2008 — Official Journal of the European Union. https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩ ↩²

4. Eating, Diet, & Nutrition for Chronic Kidney Disease — National Institute of Diabetes and Digestive and Kidney Diseases (NIH). https://www.niddk.nih.gov/health-information/kidney-disease/ckd/eat-nutrition ↩ ↩²