Does Olive Oil Ever Expire?

Extra-virgin olive oil is freshly squeezed fruit juice. I know, that might sound weird, but olives are a type of fruit, and olive oil is what you get when you crush and process them. Fruit juice. While a bottle of olive oil has a much longer shelf life than a carton of OJ, it will go bad eventually—especially if you store it improperly.

Once it has been bottled and sealed, olive oil has an 18 to 24 month shelf life. But when you open that bottle, it's best to use it within a month or two. Olive oil is not like wine, it will not improve with age. Which means you should definitely open up that fancy oil your cousin brought you from her trip to Italy that you've been saving for a special occasion.

Here's how to see if your olive oil has gone off, and what to do to extend its shelf life.

Give it the sniff test

It helps to know what fresh olive oil smells like so that you'll recognize when it goes off. Depending on the type of olives used, the oil can vary in flavor and aroma, ranging from spicy to buttery to floral. But when it is fresh, good olive oil will have a bright, grassy, "green" smell.

Taste it

Still not sure? Taste a teaspoon of the oil. Oil that has expired, was made with less-than-fresh olives, or wasn't made with olives at all (it happens!) has a flat or even musty flavor. And there won't be a peppery kick in the back of your throat—which is a good thing. According to California Olive Ranch (my favorite grocery store brand): "A mild stinging in your throat is a good thing and demonstrates that the oil is rich in antioxidants called polyphenols. Bitterness at the back of your tongue is also a good thing and is a sign that what you are tasting is indeed an extra virgin olive oil."

WATCH: How to Infuse Olive Oil

Buy dark, small bottles

We go through a steady stream of olive oil at our house, so I usually go for the largest bottle I can find. But if you aren't as heavy-handed as I am, buy it in smaller bottles. And store them in the pantry, not on your countertop. High temperatures and bright light will affect the quality of the oil. Look for bottles made of dark glass or plastic, which help protect the oil from light.