Waiter, There's a Flaw in My Wine!

By Sunny Brown

It has happened to every wine lover. After perusing the wine list for what seems like an eternity to your better half you select a bottle to enjoy with dinner. The anticipation builds as the server presents the bottle and pulls the cork. A little swirl of the glass and you are ready for the first sniff. And then it hits you like a slap across the face. Peee-uuuuwww! What is that horrible smell? Is it a barn? Or a wet basement? How about a pig sty littered with dirty socks and Limburger cheese? But what to do now? There are a plethora of wines that have flavors and aromas that can be generously described as “earthy,” “gamey,” or my personal favorite, “rustic.” But is the wine supposed to smell or taste this bad? How do you tell the difference?

There is a difference between a “flawed” wine and a bad wine. Sometimes it can be subtle, others it is plain as day. Sending back a flawed wine is perfectly acceptable behavior and should be encouraged. Sending back a bottle because you don’t enjoy the selection is a much more grey area. So with this in mind we will now present you with the most common of wine flaws, an excellent resource in deciding whether the vino is acceptable or ready for the recycling bin.

Trichloroanisole 2,4,6

Known as TCA for short, this is the most common of flaws found in a bottle of wine. Industry standards put the amount of wine with detectable amounts of TCA at anywhere between 3-5%. This chemical compound can occur naturally in cork forests but is most often caused by corks that haven’t been cleaned properly after they are bleached, a process quite common for aesthetic purposes. TCA is the cause of corked or corky wines, and causes flavors and aromas of wet cardboard or a musty, wet basement. The fruit in the wines is also muted by TCA. Wines affected by TCA can range from absolutely terrible to only slightly different from a pristine bottle, and it can be difficult in the more subtle instances to tell the difference. The prevalence of TCA has spurred the growth of alternative enclosures such as screw caps and synthetic corks, as nothing is worse than opening a bottle of Bordeaux that has been carefully cellared for ten years only to have it taste like a basement.


Also known as “Brett,” this is a specific strain of yeast that can occur in wine before and after it is bottled. The most common cause of Brett is unsanitary conditions in the winery, typically from dirty crush equipment, crush lines and especially barrels that have been contaminated as wood is impossible to fully sanitize. Brett is a hotly debated topic as in small amounts it can add complexity to a wine with aromas and flavors of leather, clove, smoke and even meatiness or bacon fat. Until the late 1980s Brett was quite common in many European and Australian wines, and often the unique qualities of these wines that has for so long been attributed to terroir was also a product of small amounts of Brett. But Brett in large amounts is more likely to be compared to band aids, dirty socks, horsiness, barn or a distinct medicinal smell. Extreme cases of Brett can be devastating to a winery, as it will spread from barrel to barrel until all of the wine is affected.


The process of Madeirizing a wine, as in the case of Madeira, is one of slowly cooking the wine over a long period of time. In this case a wine that is Madeirzed has literally been cooked, and unlike the tasty treat that is the fortified Madeira, this is not a good thing. Madeirized wines will have a dark brown color and will smell like bourbon, caramel or Sherry. This can occur if a bottle of wine is left in the sun or at too high a temperature while in storage. Send it back immediately! There are no redeeming qualities of a cooked wine.


Sulfur is an integral part of the winemaking process. It is an excellent preservative and has been used for years. However, too much sulfur dioxide can lead to aromas of burnt matches and a bitter flavor. Too much hydrogen sulfide will make a wine smell like rotten eggs and taste soapy.


Excess oxygen in the winemaking process will cause acetaldehyde to form causing a straw-like color and a distinctly acrid and Sherry-like wine. This is more common in white wines.

Malolactic Fermentation

Another necessary step in winemaking where the sharp malic acid is converted to the creamier lactic acid thus making the wine feel more round and soft. When this process is stopped or interrupted prematurely musty and swamp-like aromas can occur.

Volatile Acidity

Acidity is a natural component of wine, but too much acetic acid will make a wine seem like vinegar and it will have a prickly sensation on the tongue. Too much acetone will cause a nail polish remover-style of smell. Both can be difficult to detect in small amounts, but once recognized they should be treated with disdain.

Enough with the bad. Two things that can occur in a bottle of wine that aren’t faults are tartrate crystals and sediment. Tartaric acid forms naturally in grapes and can cause a wine to be cloudy if not removed. The easy way to remove them is to quickly cool the wine during filtration. The better way is to keep the wine at a cool temperature for a longer period of time (about 3 weeks), the tartrate crystals will form and drop harmlessly to the bottom of the wine. While they may be unattractive, they can be the sign of a well-made wine.

Sediment occurs as tannins combine with flavor compounds in the wine and fall to the bottom of the bottle. Some of these can be removed before bottling by filtering or fining the wine, but some winemakers feel that this also strips the wine of some of its flavor. Sediment will also occur as the wine ages. While excessive amounts can be a sign of a flaw, small amounts can be easily removed by decanting a wine through a screen or even a coffee filter.

Never hesitate to refuse a bottle when a flaw is present. Your local wine merchant may accept a returned bottle, but usually only if the bottle is full and you have a specific set of descriptors as to why the wine was bad. Knowing the difference will also help in the judgment of the merits of a particular wine. If you know that bottle of wine is corked as opposed to just being bad you may give it a second chance.

As far as sending back a bottle of wine that is perfectly fine but just not to your liking I have two words: Buyer beware! If the bottle was strongly recommended by the server or sommelier then you may have a case. If it is of your own selection, well, there is no substitute for experience, even if it was a bad one.