🍷 Volatile acidity
Also known as: volatile acidity, VA, volatile acids, acetic acid in wine, vinegary wine
Volatile acidity is the share of volatile acids in wine, mostly acetic acid; a trace is in every wine, a lot smells of vinegar.
Volatile acidity (VA) is the share of volatile acids in wine, and more than 93 per cent of it is acetic acid, the acid of vinegar. A little is in every wine: a sound wine fresh off fermentation holds about 0.1 to 0.4 g/L. As the number climbs, the wine begins to smell of vinegar.
The Australian Wine Research Institute (AWRI) says you can pick up the vinegar smell from around 0.1 to 0.125 g/L, and that over about 0.7 g/L it is usually counted as a defect. Ethyl acetate rides along with it and smells of nail polish remover. Sound wines carry 30 to 60 mg/L. Faulty ones carry 150 to 200.
The main culprits are acetic acid bacteria, which need oxygen. Penn State Extension lists the riskier habits: cold soaking, native fermentations, sluggish or stuck ferments, barrel ageing, long headspace exposure and bottling without enough sulphur dioxide or sterile filtration. VA often travels with oxidation. Good SO2 use, temperature control, clean equipment and sensible oxygen management keep it down.
Limits depend on where you are. The OIV, the international wine organisation, sets the maximum at 20 milliequivalents per litre, or 1.2 g/L as acetic acid, with an exception for old wines made under special rules. US federal limits are 1.4 g/L for red and 1.2 for white; Australia allows 1.5. Ordinary vinegar holds 3 to 9 per cent acetic acid, tens of times the level a wine may have.
A wine under 0.7 g/L can be blended with a cleaner one. At or above that, wineries first treat it by reverse osmosis. At that point it is closer to a flaw than a taste. Volatile acidity is a wine fault, and quite a different thing from the fresh tartness that acidity gives a wine.
Facts
| Acidity | Sound wine after fermentation: 0.1 to 0.4 g/L VA; usually detrimental above about 0.7 g/L 3 |
|---|---|
| Legal basis | OIV maximum: 20 meq/L, i.e. 1.2 g/L as acetic acid 1 |
| Taste | Vinegar (acetic acid), nail polish remover (ethyl acetate) 3 |
| Status | US federal limits: red 1.4 g/L, white 1.2 g/L 2 |
How it connects to Wine
🍷 Volatile acidity → kind of → 🍷 Wine faults → kind of → 🍷 Winemaking → kind of → 🍷 Wine
Links
- What it affects
- 🍷 Acetic acid
- Part of
- 🍷 Wine faults
Frequently asked questions
What does volatile acidity mean on a wine?
The proportion of volatile acids, mainly acetic acid. A trace is normal; a lot gives a vinegar smell.
How much volatile acidity is too much in wine?
AWRI usually counts it as detrimental above about 0.7 g/L. The OIV maximum is 20 meq/L, or 1.2 g/L as acetic acid.
Why does my wine smell like nail polish remover?
Probably ethyl acetate, which comes with high volatile acidity. Sound wines carry 30 to 60 mg/L and faulty ones 150 to 200 mg/L.
Is it true that a bit of vinegar smell is fine in any wine?
A trace of VA is in every wine, but the vinegar smell becomes noticeable from about 0.1 to 0.125 g/L and is usually seen as a flaw above 0.7 g/L.
How do wineries measure and fix volatile acidity?
Many use a Cash still, then titrate. A wine under 0.7 g/L can be blended with cleaner wine; at or above that, reverse osmosis comes first.
Similar
🍷 Reduction (wine) · 🍷 Acetic acid bacteria · 🍷 Cork taint · 🍷 Oxidation of wine · 🍷 Brettanomyces
Sources
- OIV. Maximum acceptable limits (volatile acidity)
- Penn State Extension. Volatile acidity in wine
- Australian Wine Research Institute. Recognition of wine faults and taints