Many wines are meant to be aged, but after you open a bottle, it has a shelf life. Opening a bottle of wine begins the process of oxidation, which causes the wines’ flavors and aromas to deteriorate. How long does a wine last after it’s opened? The answer depends on multiple factors.
Popping the Cork
The cork seals the wine in the bottle, creating an air-tight space where the wine receives little or no oxygen, preserving it. When you pop the cork, however, air reaches the wine, and immediate deterioration begins. Oxidation has both a positive and a negative effect on wine. For instance, many wine experts recommend letting wines “breathe” in order to soften tannins and open up the flavors of the wine. Depending on how tannic a wine is, it may need to breathe for several hours before it reaches an ideal state of oxidation. This is the principle behind decanters and aerators, which allow more air to reach wine more quickly.
If you expose a particularly delicate wine to air too long, however, the oxygen quickly converts ethanol into acetaldehyde, which can mask a wine’s flavors and aromas. Depending on the wine, this can occur in as few as two hours. This is especially true with whites and well-aged reds, which remain highly susceptible to quick oxygen damage.
How Long Does Wine Last After It’s Opened
Many factors affect how quickly a wine oxidizes once you pop its cork.
Red or White
In general, red wines oxidize more slowly than white wines. Structured red wines will last several days longer than whites. In general, a white wine lasts about three days, while a red may last up to a week. Blush wines have more in common with whites than reds, and typically last about three days after opening.
Age and Tannins
Youthful, strongly tannic wines typically last longer after opening than lighter reds, those with fewer tannins, and those that have been well-aged. For example, a young Bordeaux less than ten years of age may last for a week while a well-aged Bordeaux with soft tannins and a few decades under its belt may begin to degrade from oxidation immediately. Fruity reds, like Boujoulais Noveau, will also degrade more quickly. Delicate reds like a soft Burgundy or Pinot Noir may also degrade from oxidation more quickly. In general, plan to drink a delicate, fruity, or well-aged red within three days, while a full-bodied, tannic red may last up to a week.
Sugar and Alcohol Content
Both sugar and alcohol act as preservatives, slowing oxidation. Resultantly, dessert wines like Eiswein and Sauternes may keep for as long as a year, as May fortified wines like Sherry or Port. Likewise, higher alcohol reds such as Zinfandel may keep a little longer than their lower alcohol bretheren. A high-alcohol Zin may last a week to ten days, depending on age, alcohol content, and tannins.
Decanting, Aerating and Amount in Bottle
The less wine remaining in the bottle, the more air there is in the bottle with the wine, leading to quicker in-bottle oxidation. Likewise, if you have decanted or aerated the wine, you may wish to drink it relatively quickly – within a day or two of opening it.
Past Its Prime
How can you tell whether a wine is past its prime? Smell it or taste it. If you detect off flavors or aromas, chances are you’ve kept an open bottle a little too long. Once a wine is past its prime, you can’t bring it back. Instead, discard the wine.
Making it Last
If you don’t think you’ll be able to drink a wine before it degrades, you can attempt to slow the oxidation process in many ways.
Cork the bottle tightly to prevent more oxygen from entering.
Pour the remaining wine into a smaller (375 mL) bottle and cork it tightly. This may add a day to the wine’s life.
Put the wine in the refrigerator, which will slow down the chemical process of oxidation. You may gain a day or two by doing so.
Use a vacuum wine preserver such as the Vacu VIN Wine Saver, which allows you to pump excess air out of the bottle and slow down oxidation. This may add a few days to the wine’s life.
Use a wine preservation system that replaces oxygen with either argon or nitrogen. This may help you gain an additional week or longer from an open bottle of wine.
Playing it Safe
As a general rule of thumb, you will be able to preserve an open bottle of wine for three days. The above factors may make this general time either longer or shorter. For best results, drink wines within a day or two of opening in order to gain maximum enjoyment from the wines you drink.
By Karen Frazier
California Wine Appellation Specialist (CWAS)
**Grabbed from: http://wine.lovetoknow.com/wine-articles/how-long-does-wine-last-after-its-opened