Corked & Faulty Wine: How to Tell
Cork taint, oxidation, reduction, re-fermentation — wine can go wrong in several distinct ways. Here's how to identify each fault and what to do about it.
· 6 min read
Key takeaways
- A 'corked' wine smells of damp cardboard or wet dog — this is TCA contamination and affects roughly 1–3% of natural cork-sealed bottles.
- Oxidised wine smells of sherry or vinegar and has lost its fruit — the result of too much oxygen contact, whether during production or after opening.
- A corked wine is not dangerous. Neither is an oxidised one. Both are legitimate grounds for returning a restaurant bottle.
- Fragments of cork in the glass are not a wine fault — they're a cosmetic inconvenience caused by a broken cork, not contamination.
Frequently asked questions
- How do I know if a wine is corked or just unfamiliar?
- Smell the cork directly — the cork end that was in the wine. A corked wine often carries the damp cardboard smell there too. If the wine smells like almost nothing and tastes flat, it may be mildly corked — TCA suppresses aroma rather than replacing it with something distinctive.
- Can I send a restaurant bottle back if it seems corked?
- Yes, always. A sommelier will taste it, confirm the fault, and replace the bottle. You should not be charged for a faulty bottle. A restaurant that refuses to replace a confirmed corked wine is not behaving correctly.
- Does natural wine smell bad on purpose?
- Some natural wine producers embrace reductive or funky aromas as part of the style. Whether struck match, barnyard, or spritz is 'character' or 'fault' is genuinely contested. Try a few from reliable producers before deciding the style isn't for you.
- What should I do with a faulty bottle I bought online or in a shop?
- Contact the retailer. Most reputable merchants will replace or refund without requiring the bottle back. Keep the cork as evidence. If multiple bottles in a case are affected, flag this — it usually indicates a production or storage issue.
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