Oxidized wine is wine that has taken in too much oxygen, and you can usually spot it in about 30 seconds. A red that has gone brick or brown at the rim, or a white that has turned deep gold or amber, is the first clue. If the glass then smells of bruised apple, nuts or flat cider instead of fresh fruit, and tastes dull with a short finish, the bottle is oxidized. It won't hurt you, but it won't taste the way the winemaker meant it to either.
That quick check covers most bottles you'll ever open. The rest of this page explains what's actually happening in the glass, how to tell oxidation apart from cork taint and vinegar, which famous wines are meant to taste this way, and what to do with a bottle that has gone over.
What is oxidized wine, chemically?
Oxidized wine is wine in which oxygen has turned some of the alcohol into acetaldehyde, a compound that smells of bruised, overripe apples. Jamie Goode, co-chair of the International Wine Challenge, names acetaldehyde as the first characteristic of oxidized wines, followed by a vinegary edge, a nutty note from a compound called sotolon, browning in the glass and a loss of fruit. His point about the mechanism is a useful one for anyone who has wondered why a sealed bottle can go off: oxygen on its own isn't very reactive in wine, and it only does damage with help from traces of iron and copper plus the wine's own phenolic compounds.
The Australian Wine Research Institute puts numbers on the apple smell. It gives the sensory threshold for acetaldehyde at 100 to 125 mg/L, notes that table wines usually sit below 75 mg/L straight after fermentation, and says that above 125 mg/L the wine picks up "over-ripe bruised apples", sherry and nut-like characters. Push the process further and acetic acid bacteria convert alcohol into acetic acid, which is the same thing that makes vinegar sour. The AWRI is clear that these bacteria only become a spoilage problem when the wine is exposed to air, which is why an opened bottle on the counter is the classic route to vinegar.
The browning is the same chemistry you see on a sliced apple. Goode explains that grapes carry an enzyme, polyphenol oxidase, that browns juice exactly the way it browns cut fruit, and that later oxidation in finished wine also darkens the color. White wines show it first because they have far less of the tannin and pigment that protect reds.
How can you tell if wine is oxidized?
You can tell if wine is oxidized by checking three things in order, which are the color at the rim, the smell after one swirl, and the taste on a small sip. When at least two of the three point the same way, trust them.
Look at the rim against something white
Tilt the glass over a white napkin or a sheet of paper and look at the thin edge of the wine, where the color is easiest to read. Goode describes oxidized whites turning a more golden or orange hue with hints of brown, and oxidized reds losing their brightness until the rim goes brick red or brown. Check the vintage before you judge, because a young Pinot Grigio that pours the color of apple juice, or a two-year-old Malbec with an orange edge, should make you suspicious. Our guide to reading a wine label shows where to find the vintage when it isn't on the front. Color alone isn't proof, though, because a properly aged Sauternes, for example, takes on orange and brown hues with time and can still be in great shape.
Swirl once and smell for bruised apple
The nose is the most reliable test of the three. The Wine and Spirit Education Trust says that as oxidation progresses the fruity characteristics fade and aromas of bruised apples, nuts and honey take over. The AWRI's list runs from a simple dulling of the aroma through cardboard, straw and hay to sherry-like and "madeirised" notes. Give the glass one swirl and a sniff, then wait a moment and smell again. A wine that's just a little closed will open up with air, while an oxidized one keeps giving you the same tired, browned-fruit smell.
Take one small sip and judge the finish
Taste comes last because by now you mostly know. Oxidized wine feels flat in the mouth, the fruit drops away early and the finish is short, sometimes with a bitter or sour edge. Wine Folly describes reds that have gone this way as having "a strange vinegar-and-caramelized-apple characteristic". Dry wine can still taste lively, so the thing to judge is whether the wine has any energy left, not whether it's dry.
Is it oxidized, corked, or turning to vinegar?
Oxidized wine smells of bruised apple and nuts, corked wine smells of wet cardboard, and wine with volatile acidity smells of vinegar or nail polish remover. Those three get confused all the time, and the fix is different for each, so it's worth learning the smells side by side.
| Problem | What you smell | Usual cause | What to do |
|---|---|---|---|
| Oxidized | Bruised apple, nuts, flat cider, honey | Too much air, a failed closure, or an opened bottle left for days | Return it if freshly opened; cook with it if only tired |
| Corked (TCA) | Damp cardboard, musty cellar | A tainted cork | Return or send back; it won't air out |
| Volatile acidity | Vinegar, nail polish remover | Bacteria working in the presence of air | Pour it out if the vinegar dominates |
| Heat damage | Jammy, stewed fruit with a roasted note | A bottle stored or shipped somewhere hot | Return it; check whether the cork pushed up |
| Reduction | Struck match, rotten egg, burnt rubber | Too little oxygen during winemaking | Decant and wait; it often fades |
Cork taint is the one people most often mistake for oxidation. The WSET explains that "corked" means a wine affected by TCA, usually from a tainted cork, and that it shows as musty, damp-cardboard aromas that dull the fruit. Bits of crumbled cork floating in the glass are a different thing entirely, and the WSET says they generally don't affect the wine's aromas or flavors. Our guide to telling if wine is corked walks through that smell in detail.
Vinegar is oxidation's next step rather than a separate world. The WSET calls volatile acidity "a fault that can occur with oxidation", caused by bacteria forming acetic acid when oxygen is around, and says it's undetectable at low levels but smells of vinegar or nail polish at higher ones. The AWRI puts the nail polish smell down to ethyl acetate, which it says sits around 30 to 60 mg/L in normal wines and 150 to 200 mg/L in defective ones. Heat damage often ends in oxidation too, since Wine Folly notes that heat can push the cork out and break the seal. Reduction is the opposite fault, which the WSET ties to too little oxygen during winemaking or bottling, and Wine Folly says most of those sulfur smells burn off 15 to 20 minutes after opening, which is why a funky first sniff deserves a little air before you give up on it.
When is oxidation in wine done on purpose?
Oxidation is deliberate in Oloroso and Amontillado Sherry, tawny Port, Madeira and the Vin Jaune of France's Jura, and in those wines the nutty, bruised-apple character is the whole point. Goode lists Madeira, tawny Port and Oloroso as fortified wines aged so long in barrel that "characteristics that would be considered a fault in other wines are actually desirable here."
Vin Jaune is the most extreme example on the table-wine side. SevenFifty Daily describes it as Savagnin aged in old casks with room for air, where a film of yeast forms on the surface, and says the wines are bottled no sooner than six years and three months after harvest. Wine Spectator draws the line well, saying oxidative wines are made in a deliberate style, while oxidized wines "will also have nutty notes, but are typically out of balance, the flavors tired and stale."
Fino and Manzanilla Sherry trip people up here. They taste salty and almondy, and Goode notes that Fino carries noticeable acetaldehyde as part of its flavor, but both styles age under a protective layer of yeast called flor and aren't oxidized at all. He says a Fino has to be treated like a white wine once it's opened. Our explainer on what Sherry is and which style to order covers how flor separates the pale styles from the nutty ones.
So if you open an Oloroso and dislike it, that's a matter of taste rather than a faulty bottle, and it's useful information about your palate. Rating it in Sommy's Taste Profile feeds that dislike into the model it builds from the wines you rate, so the next recommendation knows nutty, oxidative styles aren't your thing.
How long does it take an opened bottle to oxidize?
An opened bottle of red or white wine stays relatively fresh for up to five days if you put the cork or cap back in and keep it in the fridge, according to the WSET's guide to preserving opened wine. The WSET's reasoning is that cooler temperatures slow down chemical processes, including oxidation, so the fridge advice applies to reds as well as whites.
Style changes how quickly it goes. Wine Folly says white wines are much more susceptible to oxidation than reds because the higher tannin in reds acts as a buffer, and the AWRI singles out floral whites such as Riesling as "very prone to oxidation". Sparkling wine is its own case, since the WSET says a proper Champagne stopper keeps bubbles going for up to five days and that traditional method wines like Champagne and Cava last longer than tank method wines like Prosecco. If you want to see it for yourself, Wine Folly suggests pouring one glass from a new bottle, leaving the rest for about a week, and then tasting the two side by side.
Our guide to storing open wine so it still tastes good tomorrow covers stoppers, smaller bottles and the fridge routine in more depth.
Unopened bottles oxidize too, just far more slowly. Wine Spectator's answer on an old Sauternes pointed to a crumbly cork, a dark orange color and Sherry-like flavors as the signs of a bottle that had let air in, and noted that older wines under cork are more at risk when they aren't stored at the right temperature and humidity on their side. Before you open something you've been saving, check the fill level and look for wine seeping around the cork. Our piece on how long unopened wine lasts by bottle style has the drinking windows.
What should you do with an oxidized bottle?
If a bottle you just opened is oxidized, take it back to the shop or tell your server, because Wine Folly says a wine that's oxidized right off the shelf either had a faulty closure or was mishandled in transport. You can't fix oxidation once it's happened, so there's no trick to try at home first.
At a restaurant, the sample pour exists for exactly this. Smell it, and if it's flat and appley where it should be fresh, say so politely and ask for another bottle or for someone to taste it with you. A good restaurant should replace a clearly faulty bottle without any argument. In a shop, keep the receipt and bring back as full a bottle as you can, which is also what the WSET recommends for corked wine.
If it's your own leftover bottle that has only gone a little tired after a few days, we'd cook with it rather than pour it out. A slightly flat red works fine in a braise or a pan sauce, and a tired white is still good for deglazing a pan or steaming mussels. Once it smells sharply of vinegar or nail polish, though, it'll make the dish taste of vinegar too, so let it go.
Prevention mostly happens before the wine reaches you. SevenFifty Daily calls sulfur dioxide the primary way winemakers prevent unwanted oxidation, and our explainer on wine sulfites covers why nearly every bottle contains some. At home, the useful habits are simple ones like keeping bottles away from heat and sunlight, recorking promptly and finishing light whites and sparkling wine first.
Frequently asked questions
Is oxidized wine safe to drink?
Yes, oxidized wine is safe to drink in the sense that it won't make you sick. Wine Spectator says wine that's over the hill is safe to drink but probably less pleasant to enjoy, and Wine Folly says most wine faults aren't bad for you, they just taste bad.
Can I still drink oxidized wine?
You can still drink oxidized wine, but it'll taste flat, nutty and stale rather than fresh. If it's only slightly tired, it's often better used for cooking, and if it smells of vinegar it's past the point of being enjoyable in any form.
Will I get sick if I drink oxidized wine?
You won't get sick from drinking oxidized wine. The AWRI notes that the compounds behind volatile acidity, the vinegary end of oxidation, "represent no threat to health", even though they make the wine unpleasant.
How long does it take wine to oxidize?
Opened wine starts oxidizing as soon as air reaches it, and a recorked bottle kept in the fridge stays relatively fresh for up to five days according to the WSET. Whites fade faster than reds, and Wine Folly's home demonstration of an oxidized wine is simply a bottle left open for about a week.
Why does my white wine turn brown?
White wine turns brown because oxygen reacts with its phenolic compounds, the same browning you see on a cut apple. Whites have less of the tannin that protects reds, so they darken sooner, and a white going amber well before its time is a strong sign it's oxidized.
Is oxidized wine the same as vinegar?
Oxidized wine isn't the same as vinegar, but it can become vinegar. The first stage gives bruised-apple acetaldehyde, and if air keeps reaching the wine, acetic acid bacteria convert the alcohol into acetic acid, which is what vinegar is.
Is oxidized wine always a fault?
Oxidized wine is a fault in fresh, fruity styles, but deliberate oxidation is the signature of Oloroso Sherry, tawny Port, Madeira and Vin Jaune. The WSET makes the same distinction, describing those characteristics as a fault in young wines such as Pinot Grigio and Sauvignon Blanc that are meant to taste fresh.
