Sulfites (or sulphites, SO₂) are naturally occurring preservatives added to wine during production to prevent oxidation and spoilage. Sulfites bind with acetaldehyde and other compounds, extending shelf life. Levels vary: traditional winemaking uses moderate sulfites; natural winemakers minimize or omit them. Excessive sulfites create pungent, unpleasant aromas; insufficient sulfites allow oxidation and spoilage. Sulfite sensitivity is rare (though sulphite allergies exist); most wine contains naturally occurring sulfites from fermentation regardless of additions.
WHY IT MATTERS FOR COLLECTORS
Sulfites are necessary for wine stability; wines without adequate sulfites risk oxidation and spoilage. Understanding sulfite levels helps evaluate natural wine quality and stability.
Tasting cues
- Sulfur dioxide is added (or produced) as an antioxidant and antimicrobial — not a flavour goal.
- Excess free SO₂ can prickle the nose; normal levels are usually undetectable as “sulphur taste.”
- “Contains sulfites” is a legal label line for nearly all wine above a low threshold.
Examples
- Conventional and most organic wines use sulfites; “no added sulfites” is a niche category with higher spoilage risk.
- Sensitive drinkers may react to sulfites, but histamines and alcohol are separate issues.
Cellar actions
- Do not assume zero-sulfite wine is healthier or higher quality — it is a stylistic and risk tradeoff.
- Store all wine cool; SO₂ cannot save a bottle from heat abuse.
Related terms
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