Have you ever poured a glass of wine and felt unsure? The looks, the smell, the taste, it just seemed… off? Opened or unopened, your bottle sometimes just doesn’t feel right, and you aren’t fully confident that your wine is okay to drink. To be sure, we collected a handful of tips to help you tell if your wine has actually gone bad.

To spot some of the most common tell-tale signs of a spoiled wine, start by activating your three “winetasting senses” – sight, smell, taste.

The Look

Step 1: observe your wine. You can tell a lot through the way the wine looks. But the very first sign that the wine is probably bad does not involve the beverage itself, but the cork. If you notice that the cork is slightly pushed out from the bottle, this means that the wine has overheated.

Now focus on the color. You can easily tell when a wine has lost its shine, its crispness, its color. If your wine looks like it faded and is discolored, then you are most likely about to drink an oxidized wine. Whites and reds both take on a brownish hue – a deeper yellow or yellowish brown for whites – when exposed to air. However, keep in mind that an aged wine will naturally have a slight brownish tint to it; young wines, on the other hand, fade in color only when in contact with air.

The Smell

Sometimes, your wine does not have that toasted bread or fruity aroma that is so pleasant to the nose; instead, it will have a repulsing wet cardboard, moldy basement or even wet dog smell. In that case, your wine is probably corked. TCA, the chemical responsible for that phenomenon, gives the wine those negative flavors that we’d all rather avoid. It won’t hurt you to drink a corked wine, but we cannot promise an immense gustatory pleasure…

There are a few other aromas that you may have to watch out for: ever came across a wine with a strong nail polish remover, rotten eggs or vinegar smell? There might be a little sulfur problem here, and again, although it shouldn’t be harmful to drink it, we wouldn’t advise you to – the experience is not the greatest.

The Taste

Smell and taste are two senses that naturally go hand in hand. So if you detected something odd when smelling your wine, chances are that the taste will follow. There are other signs you can easily notice when taking your first sip. Sweetness is a good indicator: if what you are drinking is not Port, then it shouldn’t taste like Port. If it does, your wine is probably bad, and this is generally due to overheating.

Last but not least: the unexpected presence of bubbles. To add a bit of fizz to our favorite sparkling wines, the wine undergoes a secondary fermentation. Some styles are naturally effervescent, such as Vinho Verde. But sometimes, that second fermentation is not meant to happen, and the result is, well, an unexpected sparkler. Make sure to check if that fizzy element is an accident or not.

Our final tip: trust your instinct! If the wine seems lifeless or off to you, then it probably is.