Wine and oxygen are frienemies. To wine, oxygen is that friend that you love to hate. In small doses you can get along, they can even spur you try something you would never consider. But too much time together and you’re going at each other’s throats, they start to bring out the worst in you, a side of yourself that you really don’t like very much. This is how wine and oxygen work. If you are not, or never were, a catty teenage girl here’s a little bit more of a breakdown.
To a certain extent wine needs oxygen, which is why it is aged in barrels. Wood has never been notorious for being airtight but it is precisely that slow flow of oxygen on the wine that helps to age it and develop the flavors. But too much oxygen is not a good thing, which is why with the exception of the barrels everything else about the winemaking process is done to minimize oxygen contact as much as possible. The wine is moved as quickly as possible into the fermentation tanks after it is crushed to avoid exposure. They often chill the wine when they are working with it because the cold temperatures slow down the oxidation process. Even those barrels are topped up as frequently as possible when the wine evaporates to try and control and limit the process. Once in bottle the cork acts slightly like the barrel, it allows a miniscule amount of oxygen in to allow the wine to age and develop in the bottle. However this process is also carefully controlled as well. Wine with corks should be stored on their side so that the cork stays moist and keep a tight seal.
But even with all these provisions in place, wines can still get too much oxygen. If you are one of those people who can have a glass out of a bottle and then stop for the night, well good for you. But you will probably also notice that is left in the bottle doesn’t quite taste the same. Maybe on the next day it’s not that noticeable, but if you have the will power to extend the bottle yet another day you should almost definitely notice a difference. Oxidized wine can not only change color, something that is easier to detect in white wines, it will also start to smell slightly pruney, liked cooked fruit more than fresh fruit. It can even take on a slightly sulfuric note. If you want to get really good at picking it out and become one of those pesky people that annoy the tasting room employees by asking how long a bottle has been open then try leaving a glass out on the counter over night. The smell should be pretty pronounced and not something you are likely to forget any time soon.