Acetic Acid (CAS 64-19-7) — Citrus Top Note Fragrance Ingredient
Acetic Acid
CAS 64-19-7
What Is Acetic Acid?
Acetic acid is the main component of vinegar, giving it its characteristic sharp, sour smell. People encounter it daily in food products, cleaning solutions, and some fragrances. In perfumery, diluted acetic acid adds a tangy, fresh quality that can brighten citrus or green accords.
Safety Profile
USE WITH AWARENESSWhat Does Acetic Acid Smell Like?
Acetic acid delivers an intensely sharp, piercing sourness reminiscent of distilled white vinegar with a slightly fruity undertone. The initial burst is aggressively acidic, mellowing into a cleaner, almost metallic dryness. In trace amounts, it adds a crisp, mouthwatering quality to citrus top notes and can enhance the green freshness of cut grass or leaf accords. The dry-down leaves minimal olfactory trace unless deliberately paired with complementary materials.
Scent Profile
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Uses acetic acid’s green sharpness to amplify the tomato leaf accord, creating an ultra-fresh vegetal effect.
Showcases acetic acid’s photorealistic quality in a single-note novelty fragrance.
2D Molecular Structure
SMILES: CC(O)=O
Chemistry, Properties & Perfumer Guide
The Chemistry
Acetic acid (CH₃COOH) is a simple carboxylic acid produced through bacterial fermentation of ethanol. Industrially synthesized via methanol carbonylation (Cativa process). The molecule’s polarity gives it high water solubility and a low odor threshold. In perfumery, typically used as glacial acetic acid (99% purity) diluted to 1-5% solutions.
Physical & Chemical Properties
| Boiling Point | 118 °C |
|---|---|
| Melting Point | 16.6 °C |
| Density | 1.049 g/cm³ |
| Vapor Pressure | 15.7 mmHg at 25°C |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.01-0.1% | Up to 0.5% | Used sparingly for lift |
| Functional Fragrance | 0.05-0.3% | Up to 1% | Cleaning product freshness |
Classic Accords
Tip: Always pre-dilute to 1% in alcohol before incorporating to avoid material degradation.
Alternatives & Comparisons
Less sharp, more cheesy nuance. Used when a softer acidic effect is desired.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. IFRA, REACH, EU Cosmetics Regulation standards update periodically. Consult current IFRA Standards Library before formulating. Not legal or regulatory advice.
IFRA Status
No IFRA restrictions. Considered GRAS for fragrance use.
GHS Classification
RIFM Assessment
RIFM evaluation confirms safe use at current industry levels.
Sustainability
Most acetic acid is produced synthetically from petrochemical feedstocks, though bio-based routes using fermented sugars exist. The carbonylation process has high energy demands but produces minimal waste. Recycling programs exist for industrial acetic acid recovery.
Explore Acetic Acid
Browse essential oils and aroma compounds.
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References
- PubChem Acetic Acid CID 176
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Mar 2026.
Report a data errorIngredient Data Sheet
CAS 64-19-7Physical Properties
| Molecular Weight | 60.05 g/mol🔬 PubChem |
| LogP (Octanol-Water) | -0.2🔬 PubChem |
| Boiling Point | 117.8 °C🔬 EPA CompTox |
| Vapor Pressure | 11.4 mmHg @ 25°C📊 OPERA |
| Flash Point | 40 °C🔬 EPA CompTox |
| Involatility Index | 1.5855💻 Calculated |
| log Kp (skin permeability) | -3.208💻 Calculated |
| SMILES | CC(=O)O🔬 PubChem |
Volatility & Performance
| Fragrance Note | Top💻 Calculated |
| Volatility Class | Fast💻 Calculated |
| Persistence Score | 0.5 / 5💻 Calculated |
Odor & Flavor
| Primary Descriptors | pungent• leffingwell |
| “Pungent, stinging sour odor, unpleasant”📖 Arctander | |
| Acetic acid, CH3COOH, is a colorless, volatile liquid at ambient temperatures. The pure compound, glacial acetic acid, owes its name to its ice-like crystalline appearance at 15.6∞C. As generally supplied, acetic acid is a 6 N aqueous solution (about 36%) or a 1 N solution (about 6%). These or other dilutions are used in adding appropriate amounts of acetic acid to foods. Acetic acid is the characteristic acid of vinegar, its concentration ranging from 3.5 to 5.6%. Acetic acid and acetates are present in most plants and animal tissues in small but detectable amounts. They are normal metabolic intermediates, are produced by such bacterial species as Acetobacter and can be synthesized completely from carbon dioxide by such microorganisms as Clostridium thermoaceticum. The rat forms acetate at the rate of 1% of its body weight per day. As a colorless liquid with a strong, pungent, characteristic vinegar odor, it is useful in butter, cheese, grape and fruit flavors. Very little pure acetic acid as such is used in foods, although it is classified by FDA as a GRAS material. Consequently, it may be employed in products that are not covered by Definitions and Standards of Identity. Acetic acid is the principal component of vinegars and pyroligneous acid. In the form of vinegar, more than 27 million lb were added to food in 1986, with approximately equal amounts used as acidulants and flavoring agents. In fact, acetic acid (as vinegar) was one of the earliest flavoring agents. Vinegars are used extensively in preparing salad dressing and mayonnaise, sour and sweet pickles and numerous sauces and catsups. They are also used in the curing of meat and in the canning of certain vegetables. In the manufacture of mayonnaise, the addition of a portion of acetic acid (vinegar) to the salt- or sugar-yolk reduces the heat resistance of Salmonella. Water binding compositions of sausages often include acetic acid or its sodium salt, while calcium acetate is used to preserve the texture of sliced, canned vegetables.📖 Fenaroli | |
Flavor Notes (Arctander)
| “Clean-sour, acid taste, perceptible well below 1% in water. Useful in flavor compositions: butter, butterscotch, cheese, chocolate, grape, raspberry, rum, spice, strawberry, vinegar, wine, etc.”📖 Arctander |
Sensory Thresholds
| Odor Detection Threshold | 35.7543 ppm (n=60)📖 van Gemert |
Regulatory Status
| FEMA Number | FEMA 2006⚖️ FEMA GRAS |
| GRAS Status | Generally Recognized as Safe⚖️ FEMA GRAS |
| IOFI Classification | Nature Identical📖 Fenaroli |
Physical data: PubChem (NIH/NLM), U.S. EPA CompTox Dashboard, EPA OPERA models, RDKit. Odor & flavor: Arctander (Perfume & Flavor Chemicals), Fenaroli's Handbook of Flavor Ingredients, Leffingwell. Thresholds: van Gemert (Compilations of Odour Threshold Values). Regulatory: IFRA Standards 51st, FEMA GRAS. Trade names: Surburg (Common Fragrance & Flavor Materials). All data compiled and cross-referenced for perfumertools.com.
Physicochemical Properties
DTXSID: DTXSID5024394
Physical Properties
| Molecular Weight | 60.052 g/mol🔬 EPA CompTox |
| Density | 1.048 g/cm^3🔬 EPA CTX |
| Boiling Point | 117.853 °C🔬 EPA CTX |
| Melting Point | 16.642 °C🔬 EPA CTX |
| Flash Point | 40.104 °C🔬 EPA CTX |
| Refractive Index | 1.376 Dimensionless📊 OPERA |
| Molar Volume | 56.175 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | -0.185 Log10 unitless🔬 EPA CTX |
| LogD (pH 5.5) | -1.294 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | -3.135 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 4.31 Log10 unitless🔬 EPA CTX |
| Water Solubility | 15.948 mol/L🔬 EPA CTX |
| Henry's Law Constant | 0 atm-m3/mole🔬 EPA CTX |
Transport Properties
| Vapor Pressure | 13.906 mmHg🔬 EPA CTX |
| Viscosity | 1.522 cP📊 OPERA |
| Surface Tension | 28.757 dyn/cm📊 OPERA |
| Thermal Conductivity | 165.776 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 37.3 Ų💻 Computed |
| H-Bond Donors | 1 count💻 Computed |
| H-Bond Acceptors | 1 count💻 Computed |
| Rotatable Bonds | 0 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 12.879 cm^3/mol📊 OPERA |
| Polarizability | 5.106 Å^3📊 OPERA |
Data Sources:
🔬 EPA Experimental data from U.S. EPA CompTox Chemicals Dashboard & CTX APIs. 📊 OPERA Predicted using EPA's OPERA QSAR models. 💻 Computed Calculated from SMILES using RDKit.
