Spoiled wine can have a range of unpleasant tastes and aromas that are indicative of its deterioration. It's essential to be able to identify these markers so that you can avoid consuming and serving bad wine.
One of the most noticeable signs of spoiled wine is an overly sweet taste in a red wine that is not intended to be sweet, such as a Cabernet Sauvignon or a Merlot. This sweetness can be a result of the fermentation process gone wrong or the presence of residual sugars that have not been properly converted into alcohol. If you find that your red wine tastes more like grape juice or syrup, it's a clear indication that something is off.
In addition to the sweetness, another red flag is the presence of fizziness or bubbles in a non-sparkling wine. This effervescence is a sign of fermentation continuing in the bottle, which should not happen in still wines. If you pour a glass of wine and notice it has a carbonated texture or produces bubbles, it's a clear indication that the wine has gone bad.
A sharp, vinegary taste is another unmistakable sign of spoiled wine. This taste is caused by the presence of acetic acid, which is produced by bacteria called acetobacters. These bacteria can spoil the wine and turn it into vinegar. If your wine tastes more like salad dressing than a pleasant beverage, it's definitely time to discard it.
It's important to note that not all spoiled wines will exhibit the same characteristics. Depending on the specific spoilage issue, the wine may display different off-putting flavors or aromas. For example, a wine that has been affected by Brettanomyces, a type of yeast, may have a barnyard or “horse blanket” aroma. Similarly, wines affected by cork taint may have a musty or moldy smell.
To avoid consuming spoiled wine, it's essential to store it properly. Keep your wines in a cool, dark place to minimize the exposure to heat, light, and fluctuations in temperature. Additionally, make sure the bottles are sealed tightly to prevent oxidation.
In my experience as a sommelier, I have encountered a few instances of spoiled wine. Once, I opened a bottle of red wine, and upon tasting it, I immediately noticed an overpowering sweetness that was not characteristic of the particular varietal. It turned out that the wine had undergone a stuck fermentation, where the yeast stopped converting sugars into alcohol, resulting in an unbalanced and overly sweet wine.
Another time, I opened a bottle of white wine, and to my surprise, it had a fizzy texture when poured into the glass. This was a clear indication that secondary fermentation had occurred in the bottle, causing carbonation. It was disappointing to have to discard the bottle, but it was necessary to avoid consuming spoiled wine.
Being able to recognize the signs of spoiled wine is crucial for any wine enthusiast or professional. By paying attention to taste, texture, and aroma, you can ensure that you only enjoy wines that are in their prime and free from any faults or spoilage.