E332I - Monopotassium citrate

At a glance

• What it is: the mono-potassium salt of citric acid; also called potassium dihydrogen citrate
• What it does: acidity regulator, buffer, and metal-binding sequestrant
• Common in: flavored waters, soft drinks, powdered beverages, jams, confectionery, and dairy-style drinks
• Label names: “monopotassium citrate,” “potassium dihydrogen citrate,” or “E332i”
• Dietary notes: made from citric acid and mineral potassium salts; suitable for vegetarian and vegan diets

Why is Monopotassium citrate added to food?

Food makers use monopotassium citrate to manage acidity (pH) and keep taste and color steady. As a buffer, it resists sudden pH changes, which protects flavor and sweetness in drinks and helps gels, jams, and candies set properly. As a sequestrant (a substance that binds trace metals), it can slow metal-catalyzed off-flavors and discoloration in foods and beverages.¹

What foods contain Monopotassium citrate?

You will most often see it in:

• Soft drinks, flavored waters, energy and sports beverages
• Powdered drink mixes and instant teas
• Fruit preparations such as jams, jellies, and dessert toppings
• Confectionery, gummies, and chews
• Dairy-style drinks and plant-based alternatives

It can appear anywhere a mild acid taste and stable pH are needed, sometimes replacing sodium-based citrates to reduce sodium content.

What can replace Monopotassium citrate?

Depending on the recipe, common substitutes include:

• Citric acid for stronger tartness without buffering
• Sodium citrates when sodium is acceptable and strong buffering is needed
• Calcium citrates in systems where added calcium is desired
• Other potassium citrates such as dipotassium or tripotassium citrate for different buffering strength

How is Monopotassium citrate made?

Industry produces citrates by neutralizing food-grade citric acid with a potassium base (such as potassium carbonate or potassium hydroxide). Controlling the neutralization step yields the mono‑salt, which is then purified and crystallized to meet food additive specifications set in the European Union (EU).² The underlying citric acid is typically made by fermenting sugars with the microorganism Aspergillus niger, a process described in U.S. regulations.³

Is Monopotassium citrate safe to eat?

The European Food Safety Authority (EFSA) re‑evaluated citric acid (E330) and its citrate salts, including potassium citrates (E332), and concluded there is no safety concern at reported uses and use levels in foods.¹ In the EU, potassium citrates are authorized food additives listed under Regulation (EC) No 1333/2008.⁴

Does Monopotassium citrate have any benefits?

From a food-technology view, it keeps flavor more consistent, balances tartness, and helps prevent off‑tastes from trace metals. It also supplies potassium, an essential mineral, but the amounts used as an additive are generally small compared with daily needs and should not be treated as a supplement source.⁵

Who should avoid Monopotassium citrate?

• People who must limit potassium (for example, some individuals with chronic kidney disease) should talk with a healthcare professional about total dietary potassium, including from additives.⁵
• Anyone advised by a clinician to follow a potassium‑restricted diet, or taking medicines that affect potassium balance, should check labels and seek medical guidance.

Myths & facts

• “It’s a harsh preservative.” In most products, monopotassium citrate’s main job is to regulate acidity and bind trace metals, not to act as a primary preservative.
• “It’s a petroleum chemical.” Food‑grade citrate salts are made from citric acid produced by fermentation, then neutralized with mineral potassium salts.²³
• “It’s a potassium supplement.” While it does contain potassium, the levels added to foods are typically small and are meant to fine‑tune taste and stability, not to meet daily potassium needs.⁵
• “It isn’t allowed in the EU.” Potassium citrates (E332) are authorized as food additives in the EU.⁴

Monopotassium citrate in branded foods

On labels you may see “monopotassium citrate,” “potassium dihydrogen citrate,” or “E332i.” It shows up often in flavored waters, soft drinks and energy drinks, powdered drink mixes, fruit spreads, and chewy candies. In some recipes it replaces sodium citrate to reduce sodium while keeping the same buffering action.

References

Footnotes

1. Re‑evaluation of citric acid (E 330), sodium citrate (E 331), potassium citrates (E 332) and calcium citrates (E 333) as food additives — EFSA Journal. https://www.efsa.europa.eu/en/efsajournal/pub/5238 ↩ ↩²

2. Commission Regulation (EU) No 231/2012: Specifications for food additives — Potassium citrates. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32012R0231 ↩ ↩²

3. 21 CFR 184.1033 — Citric acid (identity and manufacture by fermentation). https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-184/section-184.1033 ↩ ↩²

4. Regulation (EC) No 1333/2008 on food additives — Union list (Annex II). https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32008R1333 ↩ ↩²

5. Potassium — National Institutes of Health, Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Potassium-Consumer/ ↩ ↩² ↩³