Tuesday, March 20, 2018

When Good Wine Goes Bad


When Good Wine Goes Bad

At the recent AWS Pittsburgh Wine Conference and Competition, our good friend Kym Antonelli presented sessions entitled Evaluating Wine: Like a Wine Judge.  We received great responses to her presentation and information. Kym explained and demonstrated several of the wine faults that judges find in competition wine.
Statistics suggest that one in every twenty bottles of wine produced in a single year is corked and even more have been damaged by improper handling, storage or through flaws in production. Yet many of us are unaware of the faults their wine may be suffering from and can’t identify these defects when they present themselves.  
If you hand someone a carton of bad milk you get a “Yuk, no thanks!” But when good wine goes bad it’s not always simple and straightforward. Maybe the wine was hanging out on the bottom shelf with some hoodlum screw tops. Maybe it grew up in a bad environment. There are lots of different reasons that good wine goes bad.

Many of us just aren’t familiar enough with wine flaws to diagnose what’s wrong. And it can be scary to speak up since the world of wine is still an intimidating place. Knowledge is power, so below are six common wine faults and tips on how to identify them.


BRETT


What it is: Brett is short for Brettanomyces, a type of yeast that frequents wineries. It likes the phenols that make up red wine and leaves an earthy aroma to the wines when it comes in contact with them. This is one of the trickier flaws since some people enjoy a touch of Brett, and there are wineries that work with the quality rather than fight it.

How to spot it: Most commonly noticed by the smell of barnyard or Band-Aids. The University of California, Davis has tested dozens of strains of Brett and discovered that about a quarter of them add good flavors, including meaty, floral, and fruity notes. At the other end of the scale, it can add notes of rotten meat, sewer gas, and burned beans. A hint of leather or bacon might not be a bad thing, but a full hit of dog park probably means it’s time to send the bottle back.

COOKED


What it is: This flaw is just what it sounds like. The wine has been allowed to overheat. In the process it’s either lost some of its power or become stewed tasting, like over-brewed tea. This can be caused by a number of factors, like sitting on a loading dock in hot temperatures, or being stored in a basement next to the water heater. Most wineries try to avoid cooking their wines by not shipping in the summer or by using package inserts that register when temperatures go above tolerance levels. But overall, the average consumer is still pretty much at the mercy of suppliers.

How to spot it: Sometimes it’s easy. The cork might stick out from the neck of the bottle slightly, having been forced out as contents heated and expanded. Other signs include streaky wine stains on the sides of the cork. If the damage is not severe you might simply detect raisin-like, stewed fruit aromas in the wine.



CORKED



What it is: A big problem and one that’s also easily misunderstood. After all, aren’t most wines corked, as in sealed with a cork? When used to describe a flaw, however, “corked” means that the wine has come into contact with a chemical known as TCA (short for 2,4,6-trichloranisole). This chemical forms when natural fungi come into contact with chlorophenols in plant matter. Exposure to TCA is harmless at low levels, but it will wreak havoc on wine. Although it can contaminate barrels and bottling lines, it is most closely associated with use of natural cork. Estimates vary on the amount of contamination exists today in the global supply of cork stoppers. The commonly quoted figure is 3%, although other estimates are higher.

How to spot it: Despite what you may have seen in old movies, you’re not going to detect cork taint from sniffing the cork. It also has nothing to do with little pieces of cork that crumble into the wine. You’ll detect it by sniffing the wine and noticing a smell like wet, musty newspapers, wet cardboard or moldy basement. It doesn’t take a lot of TCA to make an impact; most people can smell it at 10 parts per trillion. (For reference, one part per trillion is like mixing one drop of red dye into 20 Olympic-sized swimming pools.)

OXIDATION


What it is: This is another one of those “good news - bad news” issues. Oxidation is what happens when you cut up fruit and leave it out on your kitchen counter. Some wines are improved by oxidation, and in fact their style is meant to be oxidized (think Madeira and Sherry). Also, older wines are transformed by the tiny bit of oxygen that has passed through the cork during long storage and bottle age. But a wine like a young Sauvignon Blanc will definitely suffer if it has gotten too much air.

How to spot it: Color is a common tip-off to oxidization. Reds turn brick-red or brown; whites turn amber or gold-brown. In terms of aroma, white wines can smell like apple cider or Sherry. Red wines will smell flat and sometimes have a caramel quality.

REDUCTION


What it is: This is the opposite of oxidation. The wine hasn’t gotten enough exposure to oxygen during its production and cellar and bottle aging, usually due to wine making techniques aimed at reducing oxidation flaws.

How to spot it: A reduced wine has an odor of sulfur, like burnt matchess. It can sometimes be fixed by decanting the wine. Another trick to fix a reduced wine is to drop a small piece of copper, even a (clean) pre-1980s penny, into the wine. The copper binds with the sulfur and makes it unavailable to your nose and tongue.


VOLATILE ACID


What it is: Volatile acid, known as VA, occurs naturally in wine and is usually caused when bacteria create acetic acid, the substance that gives vinegar its flavor. In small quantities it’s not a problem. But if particularly strong bacteria take hold and the VA gets out of control, watch out.

How to spot it: You stick your nose in the glass expecting to smell wine. You get a sharp whiff of nail polish. Often the wine will also taste like vinegar.



BONUS


There’s one more very common, but strange, thing that can happen to wine. Sometimes crystals will form in the bottom of a bottle that has been in the refrigerator for a day or two. These crystals form when potassium and tartaric acid naturally occurring in the wine combine and sink out of solution. A good winemaker will stabilize the wine so it’ll withstand typical refrigeration temperatures without forming these crystals. But if it does happen, don’t worry. This flaw is harmless (they’re basically Cream of Tartar) and happily, it’s one that won’t affect wine’s taste.

Check the blog often for more tips, news, and tasting notes!


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