Wine Fault

Sulfur Dioxide Excess

Chemical

Excess sulfur dioxide produces sharp burnt-match, rubber band, or metallic aromas that mask fruit. SO₂ is essential for preservation, but over-addition or poor integration creates an obvious chemical fault.

Also known as: SO₂ excess, Sulfur burn, Sulfite fault

Typical severity: Low

Cause

Over-addition of sulfur dioxide or free SO₂ remaining too high at bottling without adequate conditioning time.

How it occurs

Heavy SO₂ additions at crush, bottling, or shipping — especially in wines with low pH binding less SO₂ — leave perceptible free sulfur. Poor dissolution or timing can concentrate the effect.

Prevention

Calculate additions carefully, allow conditioning time before bottling, and taste for integration. Adjust free SO₂ targets to wine chemistry.

Descriptors created

Descriptors reduced

Commonly confused with

Common wine styles

Common grape varieties

Common regions

Related winemaking techniques

Serving implications

Beginner explanation

If a young white smells like burnt matches, let it breathe — excess SO₂ often dissipates within minutes.

FAQ

Will aeration fix sulfur burn?
Often yes for excess free SO₂ — swirling or decanting releases volatile sulfur compounds and fruit may emerge.
Is this an allergy concern?
SO₂ sensitivity is real for some drinkers, but the fault described here is a sensory issue from over-addition, not trace legal levels.

Related ontology entities

See also

Fault identification guidance reflects common wine education practice and may vary by wine style, age, and context.