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What corked, oxidised, reduced and heat-damaged wine each smell like — and which one fixes itself in fifteen minutes.
If the fruit has vanished and the wine smells of damp cardboard, a wet dog or a cellar that needs airing, it is corked. Cork taint never blows off. Pour it away and open something else.
Corked is the only fault most people can name, so it gets blamed for all the others. You are as likely to have a bottle that cooked in a delivery van, or one that needs fifteen minutes of air.
Do these in order; how to taste wine covers step four.
Cork taint is 2,4,6-trichloroanisole, or TCA, formed when moulds meet chlorine residues in cork bark, barrel staves or cellar timber. Most people start to notice it somewhere around one or two nanograms per litre — parts per trillion.
Here is the useful part, and it is stranger than the usual explanation. Takeuchi, Kato and Kurahashi, writing in PNAS in 2013, recorded single olfactory receptor cells and found that TCA evokes no odorant response of its own. It suppresses the cyclic nucleotide-gated channels those cells fire through — and it did so at attomolar concentrations, far below anything you could taste. Cork taint is not a smell added to the wine. It is your nose being turned down. The wet-dog stink is the severe case. The common one is a wine that seems oddly quiet and finishes early — you sniff, think “fine, I suppose”, and drink it anyway. It is a packaging failure, not a bad producer: the next bottle is usually lovely.
| What you smell | What it is | Verdict |
|---|---|---|
| Bruised apple, stale walnut, sherry where none belongs | Oxidation | Reject. It does not recover |
| Struck match, rubber, drains | Reduction | Swirl hard or decant; usually gone in 15 minutes |
| Stewed and raisiny, cork pushed up | Heat damage | Reject. Blame the delivery |
| Cooked cabbage or wet wool in a white | Light strike | Reject |
| Vinegar, or nail-varnish remover | Volatile acidity | Reject |
| Farmyard, sticking plasters, smoked bacon | Brettanomyces | Your call — see below |
Light strike is riboflavin attacking methionine under bright shop lighting, throwing off sulphur compounds that taste of cooked cabbage; Champagne and pale rosé in flint glass suffer worst. Brett is a judgement rather than a fault: a trace in an old-school Northern Rhône red is character, but once you cannot find the fruit under the farmyard, send it back.
Ask rather than announce. “Would you mind smelling this? I think it might be corked.” That hands the sommelier the decision, and a good one replaces it without debate. Say it at the tasting pour, not two glasses in. That pour checks for faults, not for whether you like the wine: a sound bottle you dislike is still yours, so the brief you give before ordering matters more.
In a shop, keep the cork and most of the wine, and take the receipt. The Consumer Rights Act 2015 gives you 30 days to reject faulty goods outright and take the cash back — but read the clock carefully, because it starts the day the bottle is delivered to you, not the day you pull the cork. Buy a case to lay down and the short-term right is long gone by the time you find the fault. You are not out of luck: for six months after delivery the law presumes the fault was there all along, so the burden is on the shop to show otherwise — it just means a replacement rather than a refund on demand. Finishing it first never works.
FAQ
Damp cardboard, a wet dog, or a mouldy cellar — but that is the heavy end, and it is the version everyone knows. Mild cork taint is far more common and much harder to name, because it has no signature smell at all: the wine simply tastes flat, short and stripped of fruit. TCA works mostly by subtraction, muting what the wine already had rather than laying something new on top of it.
Nobody agrees, which is itself the interesting part. Published estimates have ranged from well under one per cent to several per cent, and they disagree because the counters disagree: cork producers and wine critics are measuring different bottles, and, more importantly, no two panels draw the line at the same concentration. Every estimate is also biased low for the reason above — taint that merely flattens a wine gets recorded as a dull bottle, not a faulty one. Assume roughly one bottle in a hundred and you will not be far out.
Yes. TCA ruins the aroma at parts per trillion, concentrations far too small to do you any harm. The only reason to reject a corked bottle is that it tastes of very little, so there is nothing to be gained by persevering.
Rarely, but yes. TCA also forms in barrel staves, pallets and cellar timber, so a screwcap closes the main route in rather than every route. Screwcapped wines are instead a little more prone to reduction, which a hard swirl or a decanter usually clears.
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