Does Olive Oil Go Bad? Here’s How to Tell if Your Oil Has Gone Bad

Olive oil is a staple and the base of many diets and cuisines around the world, celebrated for its flavor and health benefits. While olive oil boasts a fairly long shelf life, it's not eternal, as some might think. There are precise rules to follow to ensure you don't ruin your dishes with spoiled oil. Here's everything you need to know.

How Long Does Olive Oil Last, Unopened and Once Opened?

When properly stored, olive oil can maintain its quality for a considerable amount of time. Unopened olive oil typically has a shelf life of 18 to 24 months from the date of bottling. However, once opened, the clock starts ticking faster. Exposure to air, light, and heat accelerates the oxidation process, which can deteriorate the oil's flavor and nutritional value. An opened bottle of olive oil should ideally be used within 6 months, although it can still be acceptable for up to a year if stored correctly in a cool, dark place with a tightly sealed cap.

So, what about olive oil that's been sitting around for 5 years? Even if unopened, oil that old is likely past its prime. Although it may not be harmful to consume, the oil's taste, aroma, and health benefits will have significantly degraded. For the best culinary experience and to reap the health benefits, it's advisable to replace olive oil that is more than two years old, even if it has been stored properly.

How to Tell if Olive Oil Has Gone Bad

Determining if olive oil has gone bad can be straightforward if you know what signs to look for. Fresh olive oil has a distinctive, often fruity aroma, and a vibrant, slightly peppery flavor. As it spoils, these qualities diminish. Rancid olive oil typically has a stale, musty smell reminiscent of crayons or putty, and a flat, greasy taste. The color might also change, although this is not the most reliable indicator due to the natural variance in olive oil colors.

If you notice any unusual or off-putting smells or flavors, it's best to err on the side of caution and discard the oil. Visual cues such as cloudiness or separation can also indicate spoilage, but these can sometimes occur naturally without affecting the oil's quality, so they should not be the sole basis for judgment.

Is It Safe to Use Expired Olive Oil?

Using expired olive oil is generally not recommended, especially for culinary purposes where flavor and nutritional content are paramount. If the oil is unopened and has passed its expiration date, it might still be safe to use, but its quality will be significantly compromised. The antioxidants and healthy fats that make olive oil beneficial will have degraded over time, reducing its health benefits.

For opened, expired olive oil, the risks are higher. As the oil has been exposed to air, it’s more prone to rancidity, which not only affects the taste but can also introduce potentially harmful compounds. Using rancid oil in cooking can spoil the flavor of your dishes and may cause digestive discomfort.