Wine tasting might be your favorite pastime, but that doesn’t mean you won’t encounter a bad bottle once in a while. This is actually fairly normal, and with a little practice, you’ll become a pro at spotting (and smelling) these flaws. Here are eight of the most common flaws, plus a couple tips for stopping these problems before they start.
Sometimes wine comes into contact with the chemical TCA, which stands for 2,4,6-trichloroanisole. It’s a long, complicated name, but all you really need to know is that this is what forms when natural fungi and chlorophenols in plant matter come into direct contact. Corked wine sometimes smells moldy, and will have a flat, dull taste. This is rather rare and affects about 3 percent of wines with natural cork.
When wine is allowed to overheat, it becomes cooked. Similar to over-brewed tea, overheated wine has a flat or stewed taste. How exactly does this happen? Sometimes all it takes is sitting somewhere with a high temperature, like a loading deck. On the flip side, being stored in a basement beside a water heater has the same effect.
You've probably heard about oxidation before and there's a good reason why. As the most common of the wine flaws on our list, oxidation can and does happen at any point during the winemaking process. Too much oxygen in the wine causes the chemical balance to weaken. In simple terms, the wine flavor tastes dull, flat or bitter.
On the other end of the spectrum, reduction happens when wine does not get a sufficient amount of oxygen exposure during the aging process. Sulfur odors, like rotten eggs or burnt rubber, are telltale signs that this is the issue. Decanting has been known to fix this problem and another tip is to drop a piece of copper (try a penny) into the wine.
Brett stands for Brettanomyces, which is a type of yeast very common in wineries. Why? Well, because the yeast is attracted to the phenols in the wine. For some, this isn't really a flaw but more of a taste preference. Flavors like floral and fruity notes are pleasant for most while others, like rotten meat and burned beans, aren't.
In an effort to prevent oxidation and keep bacteria at bay, sulfur is added during the winemaking process. Usually sulfur goes unnoticed, but that's not always the case. There are four components that can wreak havoc on an otherwise good bottle: sulfur dioxide, hydrogen sulfide, mercaptans and dimethyl sulfide. You’ll smell asparagus as a result.
7. Volatile Acidity
With a name like volatile acidity, this can't be good. Also known as VA, this is a natural occurrence in wine. Most times, it's caused when bacteria create acetic acid. This generally isn't a problem in small quantities, but it can be with bigger quantities. If the wine smells or tastes like vinegar, that's a pretty solid clue you’re dealing with VA.
When a wine starts fermenting again while in the bottle, this is called refermenting. For this to happen, there must be yeast and sugar remains in the bottle. Curious what happens next? Well, the yeast gets hungry and begins eating the sugar, resulting in mild bubbles in the wine. This isn’t the worst thing, but the taste is not pleasant.
How Can You Prevent These Flaws?
Get a Wine Fridge
This is something both winemakers and drinkers can do, as refrigeration can eliminate flaws like sulfur compounds. That said, heat damage is not fixable. If you have a wine fridge, set the temperature to 55 degrees Fahrenheit. Ideally, you'll also want 70 percent humidity. Also make sure to keep the wine away from harsh lighting and natural (or artificial) light.
Smell the Signs
Even if you're doing everything right, there might still be a flaw or two in your bottle. The best way to spot flaws is to look for the warning signs. Once you know what a certain odor means, you'll be better prepared to prevent the same problem in the future. Plus, practice makes perfect and we can think of worse ways to pass the time!
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