What is E260?

Complete guide to understanding E260 (Acetic Acid/Vinegar) in your food

The Quick Answer

E260 is acetic acid, the weak organic acid that gives vinegar its characteristic sour taste and pungent smell—the main active ingredient in vinegar, typically comprising 4-8% of vinegar by volume.

It’s used in food primarily as a preservative, acidulant (acidity enhancer), and flavoring agent—preventing microbial growth through pH reduction, controlling acidity levels, and adding tangy taste to pickles, sauces, condiments, and dressings.

E260 is one of humanity’s oldest and safest food additives: vinegar has been used for food preservation for over 2,000 years, making acetic acid one of the most time-tested preservation methods available.

What Exactly Is It?

E260 is acetic acid (CH₃COOH), a simple weak organic acid naturally produced through fermentation of ethanol.

When acetobacter bacteria ferment ethanol (alcohol) in the presence of oxygen, they oxidize the ethanol into acetic acid—the fundamental chemical process that creates vinegar. This is a completely natural fermentation process that has occurred for millennia.

Acetic acid is fundamentally different from strong acids like hydrochloric acid or sulfuric acid. It’s a “weak” acid, meaning it only partially dissociates in water, making it mild enough for food use yet effective enough for preservation.

Chemical composition:

• Molecular formula: CH₃COOH
• IUPAC name: Ethanoic acid
• CAS Number: 64-19-7
• Molecular weight: 60.05 g/mol
• Molar mass: 60.052 g/mol
• Density: 1.049 g/cm³ (glacial acetic acid); varies with concentration
• Melting point (glacial): 16.6°C
• Boiling point: 118.1°C

How it’s made:

E260 is produced using two primary industrial methods:

• Method 1 – Fermentation (traditional/natural): Ethanol is fermented by acetobacter bacteria in the presence of oxygen. The bacteria oxidize ethanol to acetic acid. This is how vinegar is traditionally made. This method produces “natural” acetic acid from biological fermentation.
• Method 2 – Chemical synthesis (industrial): Methanol is carbonylated (carbon monoxide added) in the presence of a catalyst to produce acetic acid. This is the dominant modern industrial method. This produces chemically identical acetic acid but through synthetic rather than biological means.

Fermentation process:

Ethanol + Oxygen (via acetobacter bacteria) → Acetic acid + Water

C₂H₅OH + O₂ → CH₃COOH + H₂O

Where You’ll Find It

E260 appears in an enormous range of food products:

• Pickles and pickled vegetables (most iconic use) – preservation and flavor
• Sauces: ketchup, mustard, hot sauce, Worcestershire sauce
• Dressings: vinaigrettes, salad dressings, mayonnaise
• Condiments: relishes, pickled onions, capers
• Canned fruits and vegetables (especially tomato products)
• Soft drinks and beverages (provides tartness)
• Marinades and meat preparations
• Baked goods and breads
• Confectionery (very small amounts)
• Soups and broths
• Cheese products
• Processed meats and sausages
• Oils and vinegars (food category itself)
• Fish and seafood products

Regulatory use scope: EFSA approves E260 for use in virtually all food categories with “Group I” classification, which means “quantum satis” (use as much as technologically necessary with no specific maximum limits). This reflects exceptional safety confidence.

E260 is one of the most widely used food additives globally, though consumers often don’t think of it as an “additive” because it’s simply vinegar—a food ingredient used for thousands of years.

Why Do Food Companies Use It?

E260’s primary function is preservation through antimicrobial action and pH reduction.

Food manufacturers use acetic acid for multiple strategic advantages:

• Antimicrobial preservation: Inhibits growth of bacteria, molds, and fungi; prevents spoilage
• pH reduction: Lowers pH to create hostile environment for pathogenic microorganisms
• Botulism prevention: Prevents Clostridium botulinum (botulism bacteria) growth—critical for canned foods
• Mold inhibition: Particularly effective against mold; extends shelf life
• Flavor enhancement: Adds characteristic tangy, sour, vinegary taste
• Taste improvement: Masks unwanted flavors; enhances savory notes
• Acidity control: Controls and maintains desired pH level
• Water activity reduction: Interferes with microbial growth mechanisms
• Cost efficiency: Inexpensive; highly effective at low concentrations
• Synergistic preservation: Works better with salt and other preservatives
• Natural perception: Vinegar-based—strong “clean label” appeal
• Flavor stability: Prevents oxidative off-flavors
• Thermal stability: Remains stable at processing temperatures
• No chemical taste: Unlike some synthetic preservatives, recognized as natural flavor
• Consumer acceptance: Familiar ingredient used for centuries; no controversy
• Regulatory universality: Approved worldwide with no restrictions

Unique preservation advantage: E260 is nearly irreplaceable for pickling and preservation of low-acid foods. By lowering pH below 4.6, acetic acid prevents botulism—a critical food safety function. This is why pickling with vinegar has been the gold standard preservation method for millennia.

Is It Safe?

E260 is one of the safest and most comprehensively approved food additives.

Regulatory approval:

• FDA approved: Generally Recognized As Safe (GRAS) as preservative, flavor agent, pH control agent, and acidulant
• EFSA approved: Classified in “Group I” (unlimited use permitted in all food categories); no restrictions
• JECFA approved: ADI “not specified” (no safety concerns identified)
• Food Standards Australia New Zealand: Approved with code number 260
• UK Food Standards Agency: Approved food additive
• International approval: Approved by virtually all regulatory bodies worldwide

Safety profile:

• ADI status: “Not specified” by JECFA—indicating no safety concerns whatsoever
• Natural occurrence: Found in all fruits, fermented foods, and naturally produced by human metabolism
• Body production: Acetic acid is a normal metabolite; body produces it from various foods
• Acetate metabolism: Completely metabolized through normal metabolic pathways
• No documented toxicity: No toxicity documented at any food use level
• No carcinogenicity: No evidence of cancer-causing potential
• No reproductive effects: Safe for pregnancy and breastfeeding
• No genotoxicity: No evidence of genetic damage
• Centuries of safe use: 2,000+ years of safe human consumption
• Familiar use: Vinegar is a common household food item
• No bioaccumulation: Does not accumulate in tissues
• Low acute toxicity: Would require massive quantities to cause any harm
• Normal diet component: Naturally present in fermented foods, fruits, and as body metabolite

Important safety context: The GRAS status of E260 reflects absolute regulatory confidence. There are essentially no documented adverse health effects from acetic acid at food concentrations in any population.

Natural vs Synthetic Version

E260 can be either naturally derived (fermentation) or synthetically produced (chemical synthesis):

Source and production:

• Natural method: Fermentation of ethanol by acetobacter bacteria—produces “vinegar”
• Synthetic method: Methanol carbonylation via chemical catalysis—produces chemically identical acetic acid
• Final product: Chemically identical CH₃COOH regardless of production method

Perceived “naturalness”: E260 from fermentation is considered “natural” or “natural-origin.” E260 from chemical synthesis is technically “synthetic” despite being chemically identical. However, both are approved as GRAS, indicating both sources are equally safe.

Vegetarian/vegan/dietary status:

• Vegan: Yes—whether from plant fermentation (vinegar) or chemical synthesis
• Vegetarian: Yes
• Kosher: Yes
• Halal: Yes (when ethanol source is compliant for fermentation method)
• Gluten-free: Yes
• Dairy-free: Yes

Natural Alternatives

Want to avoid E260 or looking for alternative preservatives and acidifiers?

Some alternatives include:

• E262 (Sodium acetate) – Sodium salt of acetic acid; similar preservation; provides sodium
• E263 (Calcium acetate) – Calcium salt of acetic acid; provides calcium instead
• E261 (Potassium acetate) – Potassium salt of acetic acid; provides potassium instead
• E270 (Lactic acid) – Occurs in fermented foods; different flavor
• E296 (Malic acid) – Apple acid; naturally occurring
• E330 (Citric acid) – Most common alternative acidifier
• E334-E337 (Tartrates) – Naturally occurring acid salts
• Traditional vinegar: Direct use instead of concentrated acetic acid
• Lemon juice or citrus juices: Natural acidification
• Traditional salt pickling: Old-fashioned preservation without acids
• Natural fermentation: Lacto-fermentation without added acids

The Bottom Line

E260 (acetic acid) is the main component of vinegar, used as a preservative, acidulant, and flavoring agent in pickles, sauces, condiments, and countless other foods.

It’s approved by the FDA, EFSA, JECFA, and virtually all regulatory bodies worldwide with ADI “not specified,” indicating exceptional safety confidence.

Key advantages: E260 is exceptionally safe because it’s literally vinegar—used safely for over 2,000 years. FDA GRAS approval indicates complete safety. ADI “not specified” shows no safety concerns. Produced naturally by human metabolism. EFSA “Group I” unlimited use reflects complete regulatory confidence.

Historical significance: E260 is one of humanity’s oldest preservation methods. Before refrigeration, pickling with vinegar (acetic acid) was the primary method of preserving vegetables and fruits—a role it continues to fill today.

For consumers: E260 is an excellent choice—one of the safest additives available. It’s either naturally derived (fermentation) or chemically synthesized but chemically identical either way. Familiar, time-tested, widely used, and completely safe.

Unique status: E260 is unusual among food additives in that consumers often don’t recognize it as an “additive”—it’s simply “vinegar,” a traditional food ingredient. This reflects its exceptional status as a non-controversial, universally accepted preservation method.