Why is my flat wine fizzy?
As an expert sommelier and brewer, I have come across this issue of flat wine becoming fizzy on a few occasions. It can be quite a surprising and frustrating experience for wine enthusiasts, especially if they were not expecting a sparkling wine. So, why does this happen?
1. Re-fermentation in the bottle: The most common reason for flat wine becoming fizzy is re-fermentation in the bottle. This occurs when residual sugars or yeast present in the wine undergo a secondary fermentation, producing carbon dioxide gas. This process is similar to what happens in the production of sparkling wines like Champagne, where sugar and yeast are intentionally added to create the bubbles. However, if this re-fermentation occurs unintentionally in a still wine, it can lead to unexpected effervescence.
2. Temperature fluctuations: One of the main causes of re-fermentation in the bottle is temperature fluctuations. If the wine is exposed to high temperatures during storage or transportation, the yeast present in the bottle can become active again and start fermenting the remaining sugars. This can happen on a ship or truck during long journeys, in a warehouse with inadequate temperature control, or even in a warm basement of a cheap liquor store.
3. Incomplete fermentation during winemaking: Another reason for re-fermentation in the bottle could be incomplete fermentation during the winemaking process. If the winemaker fails to fully ferment the wine or leaves residual sugars in the bottle, there is a higher chance of re-fermentation occurring later on.
4. Contamination: Sometimes, the presence of wild yeast or bacteria in the wine can also cause re-fermentation. This can happen if the winemaking equipment or storage containers are not properly cleaned and sanitized. These microorganisms can consume the remaining sugars and produce carbon dioxide.
5. Poorly sealed or faulty bottles: In some cases, the issue may not be related to the wine itself but rather to the quality of the bottle closure. If the bottle is poorly sealed or has a faulty closure, it can allow air and yeast to enter, leading to re-fermentation.
Preventing re-fermentation and fizzy wine:
1. Proper storage: To avoid re-fermentation in the bottle, it is crucial to store wine at a stable and cool temperature. Ideally, wines should be stored between 50-55°F (10-13°C). Avoid exposing the wine to extreme heat or cold, as these temperature fluctuations can activate the yeast and lead to re-fermentation.
2. Check for signs of re-fermentation before purchasing: If you are buying wine, particularly older bottles, examine them closely for any signs of fizzy wine. Look for bubbles or sediment in the bottle, as these can indicate re-fermentation. If you notice any such signs, it is best to choose a different bottle.
3. Proper winemaking techniques: Winemakers should ensure that the wine undergoes complete fermentation and that residual sugars are minimized before bottling. This involves monitoring the fermentation process closely and using proper techniques to control yeast activity.
If you find that your flat wine has become fizzy, it is likely due to re-fermentation occurring in the bottle. This can happen due to temperature fluctuations, incomplete fermentation, contamination, or faulty bottle closures. By understanding the causes and taking preventive measures like proper storage and careful wine selection, you can minimize the chances of encountering this issue. Remember to always check your wine for signs of re-fermentation before purchasing, and if in doubt, consult with a knowledgeable wine professional for guidance.