Have you ever cracked a bottle of wine, poured a glass, and took a big whiff, only to have your nostrils assaulted by the noxious fumes rising from your goblet? Chances are good that even occasional wine-drinkers have encountered a faulty wine, even if they didn’t recognize it as such. As a natural substance, wine is subject to a variety of faults—usually the result of either shoddy winemaking or bad storage.
Oxidation
This fault can be experienced by anyone who has tasted wine that has been open for a few days. However, it can occur in unopened bottles too, usually due to a damaged cork or cap. Oxidized wine is brownish in colour and stale of scent, with aromas reminiscent of bad sherry. The longer the wine is exposed to air, the more it will start to resemble vinegar.
TCA/Cork Taint
Trichloroanisole (TCA) contamination, or “corked” wine, is probably the most common (and most famous) wine fault. TCA is usually caused by a tainted cork: the high incidence of contaminated corks in the 1990s instigated the global shift towards plastic corks and screwcaps. Corked wines are devoid of fruit and smell like musty basement, wet cardboard, and/or stinky socks.
Brett
No, I’m not referring to the odour of your little brother (as apt as that may be). Brettanomyces, Brett for short, is a type of yeast that can confer disagreeable, often animal-like, aromas and flavours to a wine—think barnyards, stables, and sweaty saddles. (How Albertan!) Metallic and cheesy characteristics can also occur. As unappealing as these qualities may seem, many people praise low levels of Brett—certain French wines, especially those from the Rhône Valley, are supposed to have Brett-like characteristics—and New World winemakers often encourage this fault as it makes their wines taste more “European.”
Sulfur
There are two main sulfur faults: if your nose gets a sting of struck matches, sulfur dioxide is to blame; if you smell rotten eggs or burnt tires, hydrogen sulfide is the culprit. Sulfur dioxide is a common preservative that helps stabilize the wine and preserve its aromas and flavours when used in correct amounts. However, too much leaves you with a wine that smells flammable, not drinkable. Hydrogen sulfide forms in red wines from hot climates that haven’t had enough access to oxygen—this is perhaps why Aussies are more likely to detect this particular fault.
Cooked
The name says it all. Cooked wines have been damaged from exposure to high temperatures, having been left too long in hot trucks or a sweltering container ship. Even storing wine for a few weeks in a hot part of your house can do it. Telltale signs are pushed-up corks and sticky, leaking bottles, as well as wine that tastes dull and lifeless, with stewed fruit and prunelike aromas.
Refermentation
If you open a bottle of wine and the cork shoots out as if from a bottle of Champagne, check the label. If the wine isn’t supposed to be sparkling, then you’ve got refermentation: the wine has undergone a second fermentation in the bottle, resulting in bubbles that aren’t supposed to be there. However, keep in mind that certain white and blush wines are actually bottled with a bit of spritz in order to make them more refreshing.
Ladybugs
Weird as it may sound, ladybugs can contaminate wine. Though they are a very beneficial vineyard insect, eating aphids and other vine pests, an infestation of ladybugs often results in many of the little guys getting mixed up with the grapes in the fermentation tank. These wines smell like peanut butter, leaving you with an odd choice: do you dump the wine or drink it with a jelly sandwich?
If you detect one of these specific faults in a wine, put the cork back in the bottle and return it; most reputable stores will replace faulty bottles.
