Pro Version | USD Change Currency | Help | Mobile Site

The Science Of Decanting

Glass specialist Riedel offers wine lovers a choice of 39 different decanters
© Riedel | Glass specialist Riedel offers wine lovers a choice of 39 different decanters
Tyler Colman considers the delicate art of decanting, and why it works.

Erin Scala has a problem: she doesn’t have enough decanters.

The head sommelier at The Musket Room in Manhattan’s Nolita has only 15 decanters – quite a few shy of the 50 she would need for every wine served in the restaurant to get one. The new spot from chef Matt Lambert specializes in Kiwi cuisine and over half the wines on the list come from New Zealand. Not surprisingly, many are closed with screw caps and they get decanted whenever possible.

“Sediment is the most important thing to get off the wine,” Scala says, prioritizing the order of decanting. “Then young wines, and then red wines under screw cap.” She even pre-decants some wines in the by-the-glass section of the list by pouring the wine into a decanter and then back into the original bottle, a process sometimes known as “Bordeaux decanting.”

Why decant screw caps when there's unlikely to be any sediment? "The first thing the guest smells can be whatever gas they put in the head space of the bottle, but that blows off after a minute. So I decant every screw-capped bottle to make sure what people taste first is the actual wine," she says.

Scientifically speaking, the aromas don't actually "blow off." Decanting wine allows smelly trace components, known as thiols, to oxidize to form compounds (disulfides), which have an aroma that is much more difficult for humans to detect. 

Dr. Andrew Waterhouse of UC Davis explains: "The goal of decanting is to eliminate those chemicals from the wine and let them react with oxygen. These thiols will be removed or destroyed by the oxidation process in an hour."

Back in New York, at DBGB Kitchen and Bar, head sommelier Eduardo Porto Carreiro also loves to break out a decanter for guests. 

“The major ‘aha! moment’ for me was when I as delving into the northern Rhône,” he says. “I tend to prefer more ‘traditional’ producers and when you open them up too young, oh man, they can be reductive. If you hit them with some air it really wakes them up and makes them show better.”

Beyond syrah, Porto Carreiro cites mourvèdre and poulsard as being reductive, and he also likes to decant Loire whites.

At DBGB, the head sommelier likes to decant reds as well as Loire whites
© DBGB Kitchen and Bar/Fotolia | At DBGB, the head sommelier likes to decant reds as well as Loire whites

Wine has long been decanted to remove older wine from the sediment it throws. Yet there has been relatively little research on the science of decanting. In 2012, a team at the Shenyang School of Pharmacy set out to fill in this black hole of knowledge, embarking on a study* to investigate how decanting changed the chemical composition of a red wine.

The scientists discovered that the concentration of organic acids (which play a major role in sour flavors) and polyphenols (including tannins) decreased after decanting, which explains its mellowing effect.

Room temperature and light intensity also played a role in the decanting process, they found. Higher temperatures could lessen the sour-tasting acids, and when warmer conditions were combined with increased light intensity, the effect was to "accelerate the changes of polyphenols in red wine in decanting." So, if you are short on time and want to soften your red, put the decanter next to the fire and turn on all your lights!

However, the Shenyang researchers also revealed a drawback to decanting red wine: its antioxidant properties appeared to decrease after decanting. "Therefore, in view of the health-promoting properties of red wine intake, decanting was not suggested," the study concluded.

Waterhouse is not 100 percent convinced by the Shenyang study, questioning whether the organic acids could be destroyed so quickly. He also points out that the period used to decant their wines (up to 12 hours in one instance) is unrealistic. "It is impossible to predict how long it's going to take to get rid of those mercaptans [another name for thiols], but most people would get tired of waiting, so 60 minutes is more practical."

There's also a question mark over the ability of decanting to soften tannins. While there's not been any further research, Waterhouse extrapolates from chemistry.

"The amount of oxygen that reacts [with the decanted wine] is about a micromole [a scientific unit of measurement] and that’s plenty to eliminate those [volatile aroma] compounds," but the level of oxygen that would react with wine when decanting isn't enough to alter the structure of the tannins, which are much more abundant, he explains.

"That micromole is completely insufficient to do anything with the tannins – which there are 100 or 1,000 times more of. A micromole of oxygen is going to make about a 0.1 percent modification to the tannin, and the idea that this is going to change its taste is quite frankly not believable."

Waterhouse suggests that the perception of softer tannins after decanting is just that: a perception and not a reality. "If there's a change in the aroma because the negative thiols have been removed, not only does the wine smell better, it tastes better." In the same way, fruity-smelling wines seem sweeter.

Hyper-decanting using a kitchen blender or Vinturi's red wine tower
© Simone Phillips/Vinturi | Hyper-decanting using a kitchen blender or Vinturi's red wine tower

Questions remain about how much air should be introduced and in what type of vessel. One extreme method is “hyper-decanting.” This process is championed by Nathan Myhrvold, a former chief technology officer at Microsoft who has written the multi-volume opus entitled “Modernist Cuisine.”

Instead of waiting an hour or more for wine to breathe in a decanter, he advocates opening a (young) wine and blending it on high in a kitchen blender for 60 seconds. Sparky Marquis of Mollydooker has advocated pouring off a glass of wine, putting the cap back on, and then shaking the bottle. Both methods leave most wine experts as agitated as the wine.

"Decanting devices can only accelerate the speed of the oxygen introduced to the wine. Once the air is present you then have to wait for chemical reactions to occur," says Waterhouse.

Porto Carreiro agrees that it’s the "act of decanting" that matters most. When a wine needs the most air, he doesn’t take out the blender, instead opting to sit the decanter upright on a table. He carefully pours a steady stream into the middle of the decanter, creating a “mini-waterfall.”

While not every wine benefits from being decanted, more sommeliers are experimenting with this ancient art. Give it a swirl – though just how vigorous is up to you.  


What is “Bordeaux decanting”?

When Erin Scala instructs her staff to “Bordeaux decant” a wine, they know what she means: pour it off the sediment, remove the sediment from the bottle, then return the wine to the original bottle. It turns out that not everyone from Bordeaux is even familiar with the practice, as one member of the trade there expressed ignorance about such a decanting method.

But Peter M.F. Sichel, who owned Château Fourcas Hosten in Bordeaux, had this to say about the procedure: “Indeed it is widely practiced when the amount of wine being poured (at larger parties) exceed the decanters available, or if the prestigious wine needs to be emphasized at major PR functions. It is never used in smaller circles when there are sufficient decanters.”

Journal of Separation Science, 2012

Related story:

Myhrvold's Theory: Blenders Trump Decanters

Signup for our Free Weekly Newsletter

Write Comment

  • Comments

    01-Mar-2014 at 15:26:23 (GMT)

    Inspite of the few comments to "Bordeaux decanting" (which I know as "double decanting")I should like to emphasize that this procedure for me is only applicable when I come across a slightly too young wine, which I should have left lying in the cellar for another year or so! When it is opened and I have tasted it, I go for the "double decanting" and it get an extra dose of air. Mind you, "double decanting" an older wine can kill it!

  • Vanessa wrote:
    30-Aug-2013 at 20:45:15 (GMT)

    Thank you! It's very helpful article. Nevertheless, the résumé is: decant or not it's up on personal taste. No particular rules for that.

  • Dominic wrote:
    23-Aug-2013 at 10:58:08 (GMT)

    Very good article. I too know Bordeaux decanting as double decanting - we regularly use this method at wine tastings.

  • David Wright wrote:
    22-Aug-2013 at 23:45:16 (GMT)

    I'd not heard the term "Bordeaux decanting" before; I know the technique as "double decanting", and I do it for bottles of older wine I'm taking to a wine tasting. That way people can see the wine poured from the original bottle, but without risk of any deposit being stirred into the wine on the way there, or indeed while pouring.

  • David Ramey wrote:
    22-Aug-2013 at 23:31:21 (GMT)

    Tyler, the Bordelaise, at least, if not all French, distinguish "decanting" from "aerating." Older red wine is decanted to get it off its sediment; younger red wine (or white) is aerated to open it up, even if there's no sediment.

  • Wiremu wrote:
    22-Aug-2013 at 16:39:17 (GMT)

    This is the most interesting W-S article I have read to date!

Recent Stories

Numbers were down at Bordeaux's en primeur week

2013: Bordeaux's Divided Year

2013 was a vintage from hell for Bordeaux producers, but merchants are finding a bright side.

Bordeaux's Not So Greatest Hits

Jane Anson checks out some past Bordeaux vintages that make 2013 look positively stellar.

Oregon's Five Grand Cru Sites of the Future

With Burgundians arriving in their droves, Katherine Cole considers which Oregon vineyards have the potential to be the equivalent of a Burgundy grand cru.

Napa Caught Napping in American Appellation Race

How a small town in Missouri beat Napa to become the first American Viticultural Area.

Where Now For Crimean Wine?

The future of Crimea is uncertain and the local wine industry is wondering how the unrest will affect it.

Rapper Endorsement Puts Luc Belaire Rosé on Most-Wanted List

A French sparkler has emerged from the rear to grab a spot on Wine-Searcher's list of the 100 most-searched-for wines.

Chilean Immerses His Wines in Jazz

Can music change the taste of a wine? A recent experiment seems to suggest so.

Moving Military Technology to the Winery

Military technology isn't just about blowing the other guy to smithereens – it can also help you enjoy that glass of Pinot sooner than you thought.

How Long Before Napa Cabs Top $1000 A Bottle?

With 12 Napa wines selling for at least $1000 a bottle wholesale at Premiere Napa Valley, can the same price for regular releases be far behind?

British Government Stocks Some "Jolly Good" Wines

From $7 Chilean merlot to mature first growths, the British Government's cellar has a drop for all-comers.

Slow Cooking With Rollan de By's Jean Guyon

Melt-in-your-mouth beef cheek recipe

Burgundy's Spiraling Prices: Fact and Fiction

Burgundy vintners pray to St. Vincent for a bigger crop while consumers cross their palms with silver.

Berenice Lurton's Sweet and Salty Chicken

The head of Barsac's Château Climens shares her favorite recipe.

America vs. Europe: The Organic Divide

W. Blake Gray explores the debate over organic wine between the U.S. and the European Union.

Tim Adams' Lamb Shank Special

Slow-cooked lamb and a Clare Valley red is on the menu at Tim Adams' house.

Site Map About Contact Business Advertising Social