How To Be In The Know About Wine Faults
It is a comparatively rare occurrence but, yes, it can happen in the best of wines from the finest of wine producers. Sometimes, somehow, something goes wrong and the wine goes bad. Most of the time this will occur only in individual bottles and despite the inconvenience, it can only be accepted as one of those unfortunate but inevitable facts of life. You will often see novice wine drinkers, in a restaurant or at a gathering of friends, take a sip of flawed wine and glance around at their friends uncertainly. They are not quite sure of their palates and are afraid to speak up until someone else confirms the fault. Should you be served a flawed wine in a restaurant, it is perfectly reasonable to discreetly inform the server, who should be happy to replace it. Similarly, if the wine is bought from a shop the bottle should be returned (with the flawed wine still therein) for exchange or reimbursement.
So how do we know when wine has gone bad? Sometimes we can find clues in the cork or in the color of the wine, but the absolute test is in the aroma and in the tasting. These are the major faults that can occur in wine –
- Too much oxygen coming into contact with the wine. We need to be a little careful here. Small and gradual amounts of oxygen can help to bring out the glorious aromas and flavors of the wine. And controlled oxidation can produce such wonderful wines as dry sherry, Madeira, Banyuls and Maury. Excessive oxidation, however, eliminates any freshness or fruit that the wine may have. It makes it taste bitter. Usually the result of a defective closure, oxidized red wines take on a brick color and oxidized whites appear brownish. Oxidation is the most common of all wine faults.
- Heat damage. Heat is the enemy of wine. If your wine has a jammy, processed, unnaturally sweet or stewed taste it is usually the result of heat damage that occurs in the shipping or storage of the wine (or perhaps you left the bottle in your car on a hot day for too long). A clue to a bottle of wine being compromised by heat damage is when the cork protrudes from the neck of the bottle, a sign that the expansion of the heated air within the bottle has forced the cork out.
- Sulphur compounds. Sulphur is often added to wine to counteract other faults, but sometimes the sulphur can react badly and become a fault in itself. The wines will give off the smell of rotten eggs, burnt rubber or skunk. These aromas will often disappear once air gets to the wine. Decanting will usually help.
- Secondary fermentation. This is the result of residual sugar coming into contact with microorganisms within the wine. The wine will begin to ferment again. A sure sign of secondary fermentation is bubbles when there aren’t supposed to be any.
- Cork taint. This is also known as 2,4,6–Trichloroanisole (TCA) and can be a major problem as it can affect not just a single bottle but a winery’s entire production. TCA is caused by a chemical compound that most likely originates from mold growth on chlorine-bleached wine corks or barrels. Often it occurs in contaminated corks during the bottling process, though contamination may also occur in the oak barrels. The wine will show dank, earthy or moldy odors with hints of damp newspaper or smelly wet dog.
These are the most obvious faults that a wine lover will come across at some point or other in their wine-sipping lives. They can be disappointing, irritating and downright infuriating. But it must be stressed that they occur in only a very small percentage of the sum of wine produced, and that tasting faulty wine is by no means harmful. Best to accept the rare but occasional bad bottle and concentrate on all the great wine there is to enjoy out there!
Bill Stobbs, ABC Fine Wine & Spirits, wine & spirits supervisor
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