The short answer to this age-old question is it can, but it likely will not. There are several factors that will determine if your wine is safe to drink. Through what method did the wine spoil?
Aged Wine Versus Old Wine
Let’s start by getting one thing straight: drinking old wine is different from drinking aged wine. The key difference between old wine and aged wine is that the flavors of old wine spoil with time, but the flavors of aged wine improve with time. Time allows rich flavors and new textures to come through. Depending on the wine, aging time can take between five to 20 years to reach peak flavor. However, it is important to remember that not all wines are meant to be aged. If the bottle was under 30 dollars, it is definitely meant to be consumed now.
Old wine most likely refers to a bottle that has been sitting in the refrigerator for longer than we would like to admit. Usually, a bottle of wine should be finished within three to four days of opening, but we have all opened a bottle and forgotten it on the shelf.
Oxidized Wine Will Not Make You Sick
As you might already know, popping the cork to a bottle begins the process of oxidation. Oxidation is the chemical process that essentially turns your favorite alcoholic grape juice into vinegar by converting ethanol to acetaldehyde after being exposed to oxygen. It is probably the most common reason that a wine goes bad. If a wine has spoiled through oxidation, the following changes can be observed: the hue will fade to a noticeably brown color and when you pop the cork, you will notice an acidic, vinegar-like scent.
The flavor of the wine will lose its fruity notes and turn bitter. Upon tasting, you might notice stinging or burning in the mouth. A byproduct of oxidation, called acetic acid, causes the stinging or burning sensation. Tasting your oxidized wine will not make you sick, but it is certainly not going to taste very good. Remember: oxidation is not the only route of spoilage.
What About Bacteria In Wine?
It is no secret that the fermentation process involves a healthy amount of yeast and bacteria, but wine drinkers do not want any more microbes in their drink than what is necessary. Lactic acid bacteria in wine is part of what gives wine a worthy nutritional value; this is where red wine gets its healthy reputation. Although most wines have a high enough acidity to fight off a few invasive bacteria, a faulty cork can allow conditions perfect for this bacteria already in the wine to thrive. This explains most instances of bacteria spoilage.
If lactic acid bacteria has spoiled your bottle, you will be able to observe a mousy or musty scent; it will smell like a science experiment. It is not recommended to try performing a taste test in the case of suspected bacteria-spoiled wine. Just dump it and treat yourself to a new bottle because you can fall ill if the wrong bacteria enters your body; that goes for non-alcoholic beverages and food affected by bacteria as well.
My Wine Smells Like Rotten Eggs!
If a wine is left too restricted from oxygen during the winemaking process, sulfur compounds can form. Winemaking is a chemical process. What does a little sulfur do to the concoction? The smell of sulfur has, in the past, been compared to rubber or rotten eggs. For a wine that relies heavily on aromas for a full tasting experience, popping a cork to sulfur-spoiled wine can be a real disappointment. The reason sulfur comes into question is because its properties prevent the growth of mildew on grapes.
An old wives’ tale says that a penny — after being vigorously sanitized, of course — can save your bottle and rid it of that dreadful rotten egg smell. Chemists can confirm this; the copper in pennies react with sulfur compounds called thiols to mitigate the smell by creating a compound with a less offensive scent: copper sulfide. The trick also works with a silver spoon in the same way to create silver sulfide.
Boxed Wine Goes Bad Too
Wine drinkers who take their time with finishing their supply know that bag-in-box wine stays drinkable for six to eight weeks opened and six months unopened. However, when opting for a boxed wine over a bottle, you should still keep an eye on how long your boxed wine has been sitting on the shelf.
Although the plastic bag in your box is usually BPA-free, boxed wine — even unopened — expires because polyethylene in the plastic can seep into the wine. In turn, the taste of the wine can be altered, and drinking increased amounts of polyethylene cannot be too good for you either.
Save Your Wine From Spoilage
Better than debating on the drinkability of your old — and potentially spoiled — wine, there are several preventative measures you can take to keep your wine safe.
If the bottle has been previously opened, stow it in the freezer. Temperatures below freezing completely stop the oxidation process discussed earlier. As long as you can deal with a few tartrate crystals floating around when the wine returns to its liquid state, freezing is a perfect way to preserve wine. With this in mind, know that it’s not a good idea to stow a full bottle in the freezer. Liquids expand in changing into solid form, which could crack your bottle. If you opt for a box, there is nothing stopping you from freezing that too.
Sparkling wine should never be stored in a freezer. The likelihood of spoilage in sparkling wines is slimmer than others due to the high acidity that comes with carbonation. In the event that your beloved sparkling wine or authentic champagne does spoil, understand that its carbonation is not a clear indicator of its freshness. Look for signs of spoilage as if it were any other wine: color, smell and taste.
Use your best judgement in drinking old wine. Ask yourself some important questions before deciding to perform a taste test. Give it a smell, consult the experts and drink safely. Cheers!