Wine Faults: Why Does My Wine Smell Funky?


There is nothing like the anticipation of smelling a new wine for the first time. You can’t wait to see what aromas you will uncover; white flowers, luscious red fruits, or maybe lively spices. Instead you get a nose full of nail polish remover, burnt matches, or what can only be described as a wet horse.

Is it your nose? Has your sniffer lost it’s ability to sniff? Is this what the wine is suppose to smell like? Doubtful to all of the above. It sounds like you have detected a wine fault. If you aren’t sure how to tell, it can be challenging to know if the wine is bad, so let’s get familiar with the major wine faults so you can easily detect them in the future.

Types of Wine Faults

1/ Corked

You may have heard the expression ‘corked wine’ or ‘cork taint’? Not surprising since this is the most common wine fault. It’s official name is Trichloroanisole or TCA and it comes from a tainted cork, or tainted winery equipment. This fault will often increase with exposure to air so a wine that seems only slightly corked on opening will only get worse. Therefore, always reject a ‘corked’ wine even if it has low levels at first.  

How to tell if wine is corked? The wine will have a moldy smell like wet cardboard or a musty basement. At low levels these might be subtle and the wine may just lack freshness and aromas.

2/ Reduction

This is a result of a lack of oxygen in the bottle. Therefore, this fault can sometimes be reversed once the bottle is open and decanted for a while.

How to recognize it? The wine will smell like rotten eggs, boiled cabbage or even blocked drains. At low levels this can add a complexity to the wine and  often be confused with ‘minerality’.  

3/ Oxidation

This is the opposite of reduction, where too much oxygen has interacted with the wine. This occurs due to a failure of the closure, excess oxygen in the bottle, or the wine being too old.

How to recognize it? This one can sometimes be detected by the colour of the wine. The wine will be more brown and deeper in colour than it should be. Oxidized red wines will have aromas of coffee, bitter stewed fruit and lack freshness and fruitiness. Oxidized white wine will smell flat and typically have apple-cider like aromas.  

4/ Volatile Acidity

This is also known as V.A. and is caused by acetic acid produced by acetic bacteria. All wines have some level of V.A. Low levels help create complexity and fragrance in the wine. However, too much V.A. is a problem and is considered a fault.

How to recognize it? The wine will smell of nail polish remover or vinegar.

5/ Sulfur Dioxide

Sulfur Dioxide is found in all wines and plays a key role in the winemaking process. Generally, levels are higher in sweet, white wines.

How to recognize it? If too much is used the wine will smell like a recently burnt match. At lower levels it can hide the fruitiness in the wine.

6/ Cooked or Out of Condition

This a wine that is too old, or has been stored improperly. Harsh light, exposure to sun and/ or high temperatures will all cause deterioration. 

How to recognize it? The wine will have lost its freshness and taste flat and stale. The wine may also shows signs of oxidation due to high heat and therefore be more brown than it should be.

7/ Other Common Issues

There are some common issues that aren’t considered faults but are still a concern for most wine drinkers. Let’s look at those now.

  • Tiny bubbles or Spritz – If you open a bottle of still wine (not sparkling) and get the surprise of some spritz but no odor of vinegar, the wine is going through fermentation again in the bottle. It won’t hurt you and you might even like it! The wine may also be a bit hazy or cloudy due to residual yeast.
  • Crystals – If you see tiny crystals that look like sugar in the bottom of the wine bottle, or on the bottom of the cork, these are tartrate crystals. They are actually known as potassium bitartrate and are naturally forming in wine. They are formed when a method called cold stabilization is performed on a wine. If all of the potassium bitartrate is not removed, crystals will remain in the bottle. They will not affect the taste of the wine, and are considered by many to not be a fault but rather an indication that the wine is not overly processed. 
  • Sediment – This is different than crystals and can affect  the taste of the wine. During the winemaking process, particulates of grape skin, stem and seed are so small they stay suspended in the liquid. Over time, they will start to bunch together and then fall to the bottom of the bottle because they are too large to remain suspended. This sediment of tannin and other solid matter is more common in red wines and should be avoided when serving the wine. It is bitter in taste and it’s not pleasant to get a glass of wine with chunky bits in it.

 You can try to pour the wine through a sieve to remove the sediment or use a decanter and leave the last couple of inches of wine in the bottle. I know it seems like a waste, especially for expensive, old wines, but it won’t be a pleasant experience with a glass full of sediment.

8/ Brett

Brett, or it’s formal name Brettanomyces, is in a class all by itself because it is the most controversial of all the faults. Many wine lovers don’t consider it a fault at all and feel it adds complexity and character to the wine. Brett is a yeast, and can be found in white and red wine, but is definitely more common in red wines. It can  be on the grapes themselves, on the winery equipment, or in the oak barrels used for ageing.

How to recognize it? At low levels it can add spice, leather and gamey characteristics. Doesn’t sound bad right? At higher levels you will get aromas of band aids, sweaty horse, barnyard and sweaty socks. Obviously not everyone’s cup of tea. 

So there you have it, the common wine faults you may come across the next time you open up a bottle, or get served at a restaurant.  Now that you know how to tell if wine is bad you can save yourself and your friends from drinking bad wine. You can send a faulty wine back at a restaurant or return the bottle (not empty of course) back to the store for a replacement.  

Have you ever come across a bad bottle before? Which wine fault was it suffering from? Let us know in the comments.

Happy wining!




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