Aeration opens a wine, but too much will result in oxidation and therefore spoilage. Similarly, if the wine has a cork that leeks in too much air, or if a wine goes through multiple temperature changes in the bottle over a long period, oxidation may also occur.
I find oxidation to be one of the the most common wine flaws you’ll encounter, and is the main reason that I generally don’t drink wine by the glass in restaurants, unless I know they are doing enough volume, and even have a solid wine preservation system in place. I hate having to send wine back based solely on it being open a little longer than it should, therefore in smaller restaurants you’ll most likely find me enjoying a decent micro-brew beer.
How to tell if your wine is affected:
Affected wines will turn brown in color, which is easy to spot in whites, but sometimes not so much in reds, however don’t mistake a wine that has been aged for a wine that is oxidized. The taste of a truly oxidized wine will be completely flat, have zero fruit, or as though it’s had all the life sucked out of it.
Your course of action:
If you’re absolutely 100% sure the wine is oxidized, send it back. As previously stated, you’ll most frequently run into this when ordering wine by the glass in a restaurant, and the wine has been open for 3+ days.
Click here for the rest of my —-> A Guide to Wine Faults posts.