Decanting is one of those elements of wine service that remains mysterious and intimidating to many drinkers: Which wines need it? When should you do it? And how? Is it really even necessary or just a bit of wine pomp and circumstance?
Why Should a Wine Be Decanted? Get the (Sed)iment Out
Fundamentally, decanting serves two purposes: to separate an aged wine from any sediment that may have formed and to aerate a young, still-closed wine in the hope that its aromas and flavors will be more vibrant upon serving.
Older red wines and Vintage Ports naturally produce sediment as they age (white wines rarely do); the color pigments and tannins bond together and fall out of solution. Stirring up the sediment when pouring will cloud a wine’s appearance and can impart bitter flavors and a gritty texture. It’s not harmful, but definitely less enjoyable.
Decanting is simply the process of separating this sediment from the clear wine. It’s fairly safe to assume that a red will have accumulated sediment after five to 10 years in the bottle, even if this can’t be verified visually, and should be decanted.
How to Decant a Wine with Sediment
- Set the bottle upright for 24 hours or more before drinking, so the sediment can slide to the bottom of the bottle, making it easier to separate.
- Locate a decanter or other clean, clear vessel from which the wine can easily be poured into glasses.
- Remove the capsule and cork; wipe the bottle neck clean.
- Hold a light under the neck of the bottle; a candle or flashlight will work well.
- Pour the wine into the decanter slowly and steadily, without stopping; when you get to the bottom half of the bottle, pour even more slowly.
- Stop as soon as you see the sediment reach the neck of the bottle. Sediment isn’t always chunky and obvious; stop if the wine’s color becomes cloudy or if you see what looks like specks of dust in the neck.
- The wine is now ready to serve. Discard the remaining ounce or two of sediment-filled liquid in the bottle.
What Happens to Wine When You Decant It?
When you open a bottle of wine, two things start to happen—oxidation and evaporation—both of which seem to smooth out rough edges and can make a wine seem more expressive, more aromatic and better integrated.
The first thing that happens is evaporation. After a wine has been poured into a decanter, highly volatile components will move to the new headspace and then dissolve into the surface of the wine. The more you swirl or pour a wine and change up the surface, the more this can happen. Typically, the volatile compounds in a wine tend to be the less desirable notes, so evaporation will help notes of burnt matchsticks or rubbing alcohol, for example, to “blow off,” making the wine seem smoother and more appealing.
The effects of oxidation in wine happen over hours and days, not seconds or minutes. Oxidation might quickly turn a sliced apple brown, but dissolved oxygen in wine is not going to signficiantly change its major components, such as tannins, after sitting for an hour in a decanter, though there might be minor changes to some of the smaller phenolic compounds.
When to Decant a Wine Before Drinking: Aerate on the Side of Caution
The question of whether—or how long—to aerate a wine can generate extensive debate among wine professionals. Ultimately, decanting for aeration depends on the wine, what stage of development it’s in and your personal preference. Some wine lovers feel that an extra boost of oxygen can open up a wine and give it extra life. If you’ve opened a wine and it seems unexpressive upon first taste, it can’t hurt to try moderate aeration in a decanter to see if that transforms it.
Others feel that decanting makes a wine fade faster, and that a wine is exposed to plenty of oxygen when you swirl it in your glass. Plus, it can be fun to experience the full evolution of wine as it opens up in your glass; you might miss an interesting phase if you decant too soon.
Older wines tend to fade much more quickly than younger wines in the glass. So a particularly fragile or old wine (especially one 15 or more years old) should only be decanted 30 minutes or so before drinking. A younger, more vigorous, full-bodied red wine—and yes, even whites—can be decanted an hour or more before serving. You can start enjoying it right away, but if it seems inexpressive, let it sit in the decanter for another 2 to 3 hours or even longer. At some tastings, wines are decanted for hours beforehand and may show beautifully, but these experiments can be risky (the wine could end up oxidized) and are best done by people very familiar with how those wines age and evolve.
If you’re curious, experiment for yourself with multiple bottles of the same wine—one decanted and one not, or bottles decanted for different lengths of time—and see which you prefer. Even better, see if someone can set up a blind tasting of them for you. The more you start playing around with decanting, the more you’ll realize it’s not just a wine-by-wine scenario, but a bottle-by-bottle or day-by-day choice. So don't get weighed down by trying to follow a fixed set of rules.
Pro Tip: How to Decant a Really Large Bottle of Wine
Decanting a regular 750ml bottle or even a magnum of wine is easy enough, but what about a large-format bottle, such as a double-magnum or bigger? Should you use multiple decanters? Or can you use one decanter and keep refilling it after the wine is poured into glasses?
Expert sommeliers recommend that you don't interrupt the decanting process for older wines; otherwise you'll stir up the sediment, defeating the purpose. Master Sommelier Evan Goldstein shared his tips:
- Be prepared in advance with several decanters; how many depends on the size of the bottle being decanted and the size of the decanters you have available. (Decanters typically come in single-bottle and magnum sizes.)
- The process of decanting should be continuous. Once you start, don't stop until you are finished, as the wine's sediment will be agitated.
- Enlist the help of someone to keep changing/replacing decanters for you. If it's a bottle larger than a jeroboam, you'll probably need a second person to help you hold the bottle steady while decanting.
