Many factors are important to the evolution of wines as they age in the bottle. One of those factors is the introduction of very small amounts of oxygen into the wine through the cork (via closure ingress).

But the relationship between wine and oxygen is complicated.

Too little oxygen will yield reductive wines, half-suffocated and demonstrating animalistic flavors (more meaty than fruity) and less acidic. Reduced notes generally are the result of volatile sulfur compounds and may include unpleasant aromas like rotten eggs, sewage, or skunk. Fortunately, decanting reductive wines should cause these "off" aromas to dissipate.

Too much oxygen? Well, we’ve all left an open bottle on the counter overnight and come back the next day to a very different juice. Wines that have been exposed to too much oxygen and become oxidized lose their brightness and personality, become “tired” and often bitter. It is easy to recognize an oxidized wine just by looking at its color. Red wines trade their vibrant tones for a brick red or brown hue and whites will eventually turn golden-brown.

As soon as you remove the cork from the bottle to pour a glass, a large amount of oxygen is introduced to the bottle and mixes with the remaining wine, drastically speeding up the speed of oxidation. Unfortunately, once a wine has oxidized it cannot be brought back to life. But that’s where Coravin comes in. Since you are pouring wine with the cork in place, no oxygen enters the bottle and the wine on the other side of the cork will continue to age naturally.

Since some oxidation is normal and healthy as a wine ages, it can be difficult with old wines to know whether a wine is oxidized to a fault and when the oxidation is consistent with normal aging. Eventually, all wines will be “past their prime,” turning into ghosts of their former selves.

If a wine is oxidized, there could be several reasons why.

We’ve talked about a couple – wine could simply have been left open for too long or has aged too long in the bottle.

It could also be that the closure has failed. If you encounter a cork that is very dry and brittle, it may not be protecting the wine on the other side. Keep the cork moist by storing you bottles on their side with wine in contact with the cork’s surface.

Poor storage conditions could also be to blame. Heat and severe temperature swings will speed up the chemical reactions in wine, including oxidation. Check out our “Seven Deadly Sins of Wine” for more on storage.

Our advice...

- Check out WineFolly's tips for wines that you should cellar and ask the winemaker how long they should age. You can use your Coravin System to access tastes every 6 months or so to monitor the aging process so you can return to your wine at its peak. Remember, most wine isn't meant to age, so if something tastes great off the shelf plan to drink it in the next few months. Using Coravin won't slow the natural aging process of the wine.

- Store your wines on their side in a cool, dark place to allow them to age slowly.

- Don't pull the cork! Enjoy your favorite wines and leave the cork in place where it can continue to protect the wine on the other side.


Resources:

http://www.vawa.net/winemaking-articles/ACF_Paper.pdf

http://www.winespectator.com/drvinny/show/id/5146

http://winefolly.com/tutorial/wine-faults/

http://winefolly.com/tutorial/the-truth-about-oxygen-and-wine-aging/

http://www.sommelierjournal.com/articles/article.aspx?year=2008&month=6&articlenum=47

Photo Credits:

www.winefolly.com

www.winecommander.com