E260 - Acetic acid

At a glance

Acetic acid is a simple food acid used to control pH and help keep foods safe.

• Also called ethanoic acid; in Europe it is listed as E260 in the food additive system.¹
• It works as an acidity regulator and preservative, helping to control microbes by lowering pH.²
• In foods, acetic acid most often comes from vinegar, which is made by alcoholic and then acetous (acetic) fermentation of suitable raw materials.³
• Standard table vinegars contain at least 4 g of acetic acid per 100 mL by U.S. standard of identity.³
• The U.S. FDA affirms acetic acid as Generally Recognized as Safe (GRAS) when used in line with good manufacturing practice.⁴
• Concentrated “glacial” acetic acid is corrosive and not for direct consumption.⁵

Why is acetic acid added to food?

Manufacturers add acetic acid to lower the pH, which slows or stops growth of many spoilage and disease-causing microbes.² In acidified foods, processors aim for a finished equilibrium pH of 4.6 or below because this level prevents growth of Clostridium botulinum, a serious foodborne hazard.⁶ Acetic acid also gives a tangy flavor that many consumers expect in pickles, sauces, and dressings.

What foods contain acetic acid?

You will most often find acetic acid in foods that use vinegar, such as pickled vegetables, relishes, marinades, sauces, and salad dressings.³ It also appears in other “acidified foods,” where acids are added to bring pH to 4.6 or below for safety and shelf life.⁶

What can replace acetic acid?

Depending on the recipe, other food acids can supply sourness, such as citric acid, lactic acid, or malic acid. Preservatives like sorbic acid, potassium sorbate, sodium benzoate, or propionic acid may also be used where regulations allow, depending on the food type.⁷ In soft drinks, phosphoric acid is a common acidulant that provides tartness without a vinegar note.⁷

How is acetic acid made?

There are two main routes:

• Fermentation: Vinegar is made by first fermenting sugars to alcohol and then converting the alcohol to acetic acid with acetic acid bacteria (“acetous fermentation”).³
• Industrial synthesis: Most acetic acid used in industry is produced by carbonylation of methanol (reaction with carbon monoxide), yielding high-purity acetic acid.⁸

Is acetic acid safe to eat?

Yes—when used as intended in foods. The U.S. FDA lists acetic acid as GRAS for general-purpose use in food at levels consistent with good manufacturing practice.⁴ In the EU, acetic acid (E260) has been re-evaluated by EFSA, which found no safety concern at reported uses and concluded that setting a numerical ADI (acceptable daily intake) was not necessary.² Note that concentrated acetic acid is corrosive; food-grade vinegar and diluted food-use acetic acid are the appropriate forms for consumption.⁵

Does acetic acid have any benefits?

• It helps foods keep quality longer by holding pH in a range that makes it harder for many microbes to grow.⁶
• It delivers a clean, tangy sourness that many recipes rely on for balance and flavor.

Who should avoid acetic acid?

Food authorities have not set special population restrictions for acetic acid when it is used properly in foods.² People who find acidic foods aggravate reflux or heartburn symptoms may choose to limit strongly acidic items and consult a clinician about personal triggers.⁹

Myths & facts

• Myth: “E260 is different from the acid in vinegar.” Fact: E260 is acetic acid, the same molecule that makes vinegar sour; standard vinegars must contain a defined minimum of acetic acid and are made by acetous fermentation.³
• Myth: “Acetic acid is unsafe because it’s a chemical.” Fact: Regulators in the EU and U.S. permit acetic acid in foods and consider it safe at typical use levels.²
• Myth: “Acetic acid alone makes any canned food safe.” Fact: Safety depends on proper acidification (pH 4.6 or below for acidified foods) and good processing, not just adding acid.⁶

acetic acid in branded foods

On EU labels, additives are listed by function (for example, “acidity regulator”) followed by their name or E-number, so acetic acid may appear as “acidity regulator: acetic acid” or “acidity regulator: E260.”¹⁰ In the U.S., ingredients are listed by their common or usual names, so you will typically see “vinegar” or “acetic acid” in the ingredient list.¹¹ If you prefer to avoid a vinegar note, look for products that use other acidulants like citric acid instead.

References

Footnotes

1. Specifications for the identity and purity of food additives including E260 (acetic acid) — Commission Regulation (EU) No 231/2012. https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩

2. Re-evaluation of acetic acid, sodium acetate, calcium acetate and potassium acetate (E 260–263) as food additives — EFSA Journal. https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2013.3252 ↩ ↩² ↩³ ↩⁴ ↩⁵

3. Cider vinegar; identity and composition (requires acetous fermentation; ≥4 g acetic acid/100 mL) — FDA (21 CFR 169.175). https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-169/section-169.175 ↩ ↩² ↩³ ↩⁴ ↩⁵

4. Acetic acid — FDA (21 CFR 184.1005). https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-184/section-184.1005 ↩ ↩²

5. Acetic acid: hazards and precautions (corrosive at high concentrations) — NIOSH Pocket Guide, CDC. https://www.cdc.gov/niosh/npg/npgd0001.html ↩ ↩²

6. Acidified foods: definition and required pH (≤4.6) — FDA (21 CFR 114.3). https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-114#114.3 ↩ ↩² ↩³ ↩⁴

7. Food additives and their functional classes authorized in the EU — Regulation (EC) No 1333/2008. https://eur-lex.europa.eu/eli/reg/2008/1333/oj ↩ ↩²

8. Acetic acid, production and use (industrial carbonylation of methanol) — PubChem, NIH. https://pubchem.ncbi.nlm.nih.gov/compound/176 ↩

9. Eating, diet, and nutrition for GERD — NIDDK, NIH. https://www.niddk.nih.gov/health-information/digestive-diseases/acid-reflux-ger-gerd-eosa/eating-diet-nutrition ↩

10. Ingredient and additive labelling (name or E-number) — Regulation (EU) No 1169/2011. https://eur-lex.europa.eu/eli/reg/2011/1169/oj ↩

11. Ingredient labeling by common or usual name — FDA (21 CFR 101.4). https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-101/section-101.4 ↩