Volatile Acidity
Volatile Acidity
Volatile Acidity, or VA, is the sharp, vinegary edge that appears when a wine's acetic acid content climbs too high. A small amount is present in every wine and can even add lift and complexity but past a certain threshold it stops being a nuance and starts smelling like nail polish remover or salad dressing.
What does it smell like?
Nail polish remover, vinegar, or a sharp, sour edge that pricks the nose before you even taste the wine.
At low levels VA can lift aromatics and add a savoury edge many tasters barely notice; past that point it dominates and masks the fruit entirely.
Aroma Classification
VA falls outside the primary/secondary/tertiary framework it is a microbial and chemical fault, produced by acetic acid bacteria converting alcohol into acetic acid and ethyl acetate.
Nature's Influence
Climate
Warm, humid conditions during harvest and fermentation encourage the bacteria responsible for VA, particularly where fruit is damaged, over-ripe, or fermentation is slow to start.
Careful hygiene, healthy fruit and clean, timely fermentation are the real defence against VA not climate alone.
Soil & Site
Not applicable.
Vintage
Vintages with rot pressure or damaged fruit at harvest carry a higher risk of elevated VA.
Wet, rot-prone vintages raise VA risk sharply.
The Winemaker's Hand
Harvest Timing
Delayed harvest of already-compromised fruit increases the risk, since acetic acid bacteria thrive on damaged berries.
Fermentation
Slow, sluggish or stuck fermentations give acetic acid bacteria time to establish, which is why healthy yeast populations and prompt fermentation are key controls.
Extraction
Extended maceration on damaged or rotten fruit increases bacterial exposure and VA risk.
Maturation
VA can also build during barrel ageing if barrels are not kept topped up and oxygen exposure is poorly managed, since acetic acid bacteria are aerobic.
Poorly maintained, ullaged barrels are a common source of rising VA during maturation.
Sealed steel tanks limit oxygen exposure and reduce VA risk.
Once bottled, VA levels are essentially fixed and do not resolve with further ageing.
Careful topping up, temperature control and sulphur management are the standard defences during maturation.
Blending
Small amounts of VA can be blended down using cleaner batches, though this only works below a certain threshold.
Where You'll Find It
Typical Wine Styles
Traditionally tolerated at slightly higher levels in some big, rustic reds; considered a flaw at much lower levels in delicate whites.
Typical Regions
What Does It Tell You?
- Bacterial activity somewhere in the winemaking process
- Possible fruit damage or a slow fermentation
- A wine at or past its acceptable acetic acid threshold
Legal limits for VA exist in most wine-producing countries precisely because it is one of the more common and well-understood faults.
Food Pairing
Similar Aromas
Doesn't every wine have some vinegar character?
Every wine contains trace acetic acid, which is normal and often imperceptible. The fault only appears once acetic acid and ethyl acetate rise high enough to dominate the nose most tasters have a detection threshold well above what's naturally present in a healthy wine.
Learn to Recognise It
- Is there a sharp, nail-polish or vinegar smell before you even taste the wine?
- Does the wine's fruit feel thin or masked behind a sour, pungent edge?
- Does the finish feel hot and acidic rather than balanced?
- Would a second bottle of the same wine taste noticeably cleaner?
A little lift and savouriness is normal; an obvious vinegar or nail-polish smell that dominates the fruit is the fault.
Volatile Acidity is a reminder that time and exposure are not neutral forces, left unchecked, the same air that helps a wine breathe can also unmake it. It teaches the value of vigilance: that good outcomes require constant, careful choices at every stage, not just at the start.
Ethyl acetate, the compound most responsible for the nail-polish smell in high-VA wines, is the same chemical used industrially as a solvent, which is exactly why it smells so recognisable.