There's a lot to love about wine. It is delicious and is perfect for a variety of occasions. There are also so many types of wines, from light, sweet Riesling to full-bodied Cabernet Sauvignon. But if you opened a bottle, couldn't quite finish it, and are hoping to enjoy it a few days later, you might be wondering if it's OK to drink. Can wine go bad, really? After all, isn't ageing (i.e., letting wine sit in the bottle) a standard part of winemaking? Well, yes — but not all situations are created equal. Keep reading as wine- and food-safety experts break down the science behind wine spoilage, whether you can drink spoiled wine, and tips for keeping wine fresh.
Can Wine Go Bad?
Sorry, wine-lovers. Wine can definitely go bad! However, it's worth noting that wine does not "spoil" in the same way food does, according to Mary Ewing-Mulligan, master of wine, wine educator, and president of International Wine Center, an independent wine school based in New York City. Basically, food spoils when pathogenic (harmful) bacteria cause decay. In wine, on the other hand, the alcohol prevents this type of bacteria from forming or growing in the first place, Ewing-Mulligan says. So when we say wine has "gone bad," it doesn't mean it's growing gross bacteria; rather, it simply means means "it's no longer desirable to drink," Ewing-Mulligan notes.
In most cases, wine goes bad because it's been open for too long. This is mainly due to two reasons: oxygen exposure and nonpathogenic bacteria. Oxygen exposure causes chemical changes in the wine, a process known as oxidation. This can make the wine lose its vibrancy, colour, and flavour, Coly Den Haan, certified sommelier and owner of LA-based wine shop Vinovore, says. The presence of acetic-acid bacteria also contributes to spoilage, according to Kimberly Baker, PhD, RD, LD, director of the food systems and safety program team at Clemson University Extension Service. "This type of bacteria is not pathogenic," Dr. Baker says, but when wine is exposed to oxygen, this bacteria "converts the alcohol into acetic acid and acetaldehyde, causing the wine to [develop] a vinegar-like taste and smell." (For context, acetic acid is the main component in standard white vinegar.)
How to Tell If Wine Has Gone Bad
The best way to tell your wine has spoiled is to smell it. As mentioned earlier, if wine has gone bad, its odour will likely be similar to vinegar, thanks to the acetic acid. Take a whiff, and see what it smells like. If you're unable to detect an unusual smell, you can also use your taste buds, though it may be an unpleasant experience. "A spoiled wine may taste like vinegar or have an off flavour due to oxidation," Dr. Baker says.
Here are a few other telltale signs that your wine has gone bad.
- The red wine tastes sweet. If the bottle of red wine has the aroma of Port or tastes like dessert wine (even though it is neither of those two things), it has been overexposed to heat and is therefore undrinkable.
- The cork is pushed out slightly from the bottle. That's a sign the wine has overheated and expanded within the bottle.
- The wine is a brownish colour. A brown hue in red wine demonstrates that the liquid is past its prime. White wines that have darkened to a deep yellow or brownish straw colour are usually oxidised.
- You detect astringent or chemical flavours. Wine that lacks fruit, is raspy, is too astringent, or has a paint-thinner taste is usually bad.
- It tastes fizzy, but it's not a sparkling wine. A still wine that is fizzy or effervescent has undergone a second fermentation after the bottling and shouldn't be enjoyed.
Is It Dangerous to Drink Spoiled Wine?
If you've accidentally sipped on spoiled wine, don't panic. "There are few dangers of drinking spoiled wine," Dr. Baker says. That's because the wine becomes more acidic during the spoilage process, which prevents harmful bacteria from growing, she explains.
If anything, "the biggest side effect of drinking spoiled wine is an unpleasant taste in your mouth, [so] most people stop after the first gross sip," Den Haan notes. "However, in the rare instance someone decides to power on, it's extremely unlikely [the bacteria will] give you a food-poisoning-type sickness."
TLDR: drinking spoiled wine isn't dangerous, but it will not be fun.
What Should You Do With Spoiled Wine?
It can be hard to pour a beautiful bottle of wine down the drain, even if you think it's gone bad. If your spoiled wine is only slightly off, you can still drink it and make the flavour more palatable by diluting it with other beverages, such as whipping up a tasty sangria or wine spritzer. You can also cook with it or really lean into the spoil and make your own homemade vinegar. When in doubt, spoiled wine always works as a fruit-fly trap; just pour some inside a small glass or bowl, cover the top with plastic wrap, and then poke some holes in the plastic with a toothpick.
How Do You Keep Wine Fresh?
As with all good things in life, an open bottle of wine won't last forever. Still, it's possible to extend its shelf life — and avoid making an accidental batch of vinegar — by storing it properly. "There are a few options depending on the tools [you have]. Gadgets like wine pumps and wine gas can be helpful to remove or replace the oxygen that can prematurely age wine," Den Haan says. You can also use a wine-preservation system such as Coravin Timeless (£199.99) if it fits within your budget and you're serious about wine. Otherwise, "your simplest solution is to cork, screw, or stopper the wine [bottle], and pop it in the refrigerator," Den Haan shares. The cooler temperature will slow down the reactions that are responsible for spoilage, meaning oxidation and growth of acetic-acid bacteria. The exception is heavy red wine, which should be stored in a cool, dark space or wine refrigerator (if you have one), Dr. Baker says.
While you're at it, consider the amount of wine that's leftover. According to Ewing-Mulligan, the less wine there is in the bottle, the more air and oxygen there will be. This can reduce the wine's shelf life, so "if you need to keep the wine for more than a couple of days, pour the wine into a smaller bottle so there's less air space in the bottle, and then refrigerate it," Ewing-Mulligan suggests. "Cold is your best friend in keeping wine's flavour fresh."
When stored properly, an open bottle of wine will stay fresh for several days, depending on the variety, according to Dr. Baker.
- Sparkling wine: one to three days stored in the refrigerator.
- Light white or rose wines: five to seven days stored in the refrigerator.
- Full-bodied white wine: three to five days stored in the refrigerator.
- Red wine: five to seven days stored in a cool, dark place.
As for an unopened wine? Although it will have a longer shelf life than opened wines, proper storage is still essential for keeping it fresh. The total shelf life will also depend on the type of wine, according to Ewing-Mulligan. "Red wines are more durable than whites, and higher-alcohol white wines (such as Chardonnay) are more durable than delicate wines such as Moscato or inexpensive Pinot Grigio," she explains. With that being said, your best bet is to store wine in "a cool place with [minimal] temperature flux and away from direct light," Den Haan says. Also, if it has a natural cork, lay the bottle on its side, which "keeps the cork from drying out and minimises oxygen coming in." This will ensure that your wine stays fresh for as long as possible — so you can have your wine and drink it, too.
— Additional reporting by Katie Sweeney