There are numerous things that can go wrong with wine from the harvesting of the grapes, through the fermentation cycle, to the racking and aging in barrels, to the bottling process and finally waiting for the unwary wine drinker to open. Some wine faults are correctable, but many are not, and the damaged wine will need to be returned to where purchased. The burning question is when is the wine at fault, rather than a bias on the part of the wine taster?
Some wine faults are easier to detect than others and in some cases the fault might not impact the enjoyment of the wine for some drinkers. Here the discussion will focus on detectable wine faults and how they express themselves in the aroma and bouquet of the wine. Technically, aroma derives from the type of grape and bouquet from the fermentation, type of yeast employed, type of oak used, its age and the aging process itself.
The most common wine fault is oxidized wine, wherein oxygen has invaded the wine to the point where flavors have dulled and the wine develops a “Sherry-like” nose. This, of course, is fine if it is Sherry one is enjoying. While introducing oxygen into a wine glass, via swirling, decanting, or using aeration devices does open up a wine, too much oxygen will spoil the wine. Deliberately maderized wines like Madeira, from which the term derives, intentionally introduce oxygen and heat. In all other cases it was a mistake in the cycle from grape to bottle.
One of the most common places one experiences this is in a restaurant when ordering wine by the glass. How long has the bottle been opened and how well was it sealed? Does it go back into a wine chiller, or is it left out between pouring? A wine bar is usually set up to handle this and often has a fast turnaround on wine-by-the-glass requests, but a less popular wine choice on a slow day could lead to an oxidized wine. Since heat can also be a factor, an outside wine bar server needs to be more cautious in their handling of wines, and sometimes are not.
If one is not sure how to detect an oxidized wine, leave a glass of wine open all night and sniff it the following morning. Don’t worry, there is zero chance you will be tempted to taste it. The smell is all you need to remember. Once one is comfortable with detecting this wine fault, it will be far easier to tell the server your wine is oxidized, and ask him to replace it. When uncorking a bottle and discovering the same problem, one will be confident in returning it to the wine shop or winery.