Skip to main content

There is no need to panic if you find mould on the cork of that special bottle of wine that you are about to open.

Mould on aged wine bottles can, if anything, be a sign that it was stored correctly.


Why do wine corks get mouldy?

Wine cellars and refrigerators have higher levels of humidity than a standard fridge in order to prevent the corks from drying out.

Most cellars and fridges also allow bottles to rest horizontally to keep the wine in contact with the cork, preventing evaporation; however, evaporation can still happen over time.  

Humidity in wine cellars is usually between 50% and 80%. While beneficial for the corks, such high levels of humidity also encourage mold spores. As such, most wine collectors will experience mold in their cellars at some point. 

The mold in your cellar should not be a cause for concern about the wine itself.

Unless the cork has been affected and protrudes from the neck, the wine is likely to be as good as the winemaker intended.  


How to tell if wine has gone bad

If you are still concerned about your wine and whether it is safe to drink, you can read this article on how to tell if your wine has gone bad.

How to remove mould from wine bottles and corks

Mould on a wine bottle or the top of a cork and be removed by wiping with a clean, dry cloth. Ensure the cork is completely dry before resealing the wine bottle.

If you wish to clean stubborn mould from the bottle, you can clean with a solution equal parts vinegar and water; however, a vinegar solution is not recommended for the lip of the bottle. You don’t want to risk your wine tasting like vinegar!

Cork taint

Cork taint is a wine fault characterized by undesirable odors or tastes in a bottle of wine.

The cork is usually considered to be responsible, although studies have shown that other factors can also be responsible for taint; for example, wooden barrels, storage conditions and the transport of corks and wine.

Wine tainted on opening is said to be corked. Cork taint can affect all wines regardless of price and quality level.

The main cause of cork taint is the presence of the chemical compounds TCA and TBA in the wine.  

Often the compounds have been transferred from the cork, but they can also be transferred through the cork rather than from it.

Tainted wine is harmless but the wine will not taste nice.

Corked wine has a characteristic odor often resembling moldy newspaper, wet dog, damp cloth, or damp basement. It is also likely that the wine’s native aromas (fruity, floral etc.) are reduced significantly.

Decanting wine

Wine corks with mould are likely to be aged wines. Aged wines with a deposit will likely need to be decanted into a decanter.

If you don’t have a decanter, there are many ways to decant wine without a decanter.