I am so often asked why should you let wine breathe. My answer usually is, “what wines are you talking about?” If it is a hearty young red wine, then letting it breathe would be beneficial, as the process of exposing the wine to oxygen will allow the acid and tannin to mellow and soften a little. But white wines are quite different in their makeup and don’t usually need to breathe at all, but there are exceptions.
Aging benefits many wines, especially good quality red wines, so if they are aged adequately they shouldn’t need to breathe at all before being drunk. Tasting a very young wine will often cause your mouth to pucker up as the high, raw acids and harsh tannins are felt in the mouth. As the wine ages, these acids will reduce slightly while the tannins will mellow giving the wine a fuller, softer mouth feel.
However, letting a wine breathe is not merely just a matter of opening a bottle and having it stand for an hour or two. This would have absolutely no effect whatsoever as the surface area in contact with the air, in the neck of the bottle, is tiny. What is required is to decant the wine into a glass decanter or other similar vessel, allowing it to remain for at least half an hour or thereabouts.
A basic form of aeration is the process of pouring the wine boldly into a glass so that air is mixed into the wine, but this method is fairly useless unless you leave the wine for a length of time before drinking it. After all, it is the surface area of the wine in contact with the air that is key.
By allowing a wine to breathe does not always make it a better wine. However, most red wines would benefit slightly from this process whereas with a low acid white wine the oxidation process kicks in fairly quickly and the wine would lose its freshness and appeal.
Many of us have tasted a wine, and not finishing the bottle sealed it only to come back to it the next day, and comment how much better (or worse) it tasted second time round. This is partly due to the wine breathing and partly due to our perception of the wine being different on each day, i.e. our mood or the food we accompany it with has changed.
Nowadays many wines are made to be drunk whilst still very young so uncork your wine, taste it and decide whether you think it needs to breathe, then enjoy it with your friends.