Does Olive Oil Go Bad? How to Tell if It’s Rancid

Yes, olive oil can go bad, and it turns rancid over time due to exposure to heat, light, and oxygen.

Even though olive oil doesn’t spoil like dairy, it oxidizes and becomes rancid. This negatively impacts both taste and nutritional value. Using rancid oil can ruin your recipes and may introduce harmful compounds into your food.

How to Tell If Olive Oil Is Rancid

Use Your Senses:

Smell - Fresh olive oil smells grassy, fruity, or peppery. Rancid oil smells like crayons, playdough, or old peanuts (yuck).
Taste - Good olive oil has a clean, bitter, or spicy note. Rancid oil tastes flat, greasy, or just “off,” sometimes with a waxy or sour aftertaste.
Color - While color varies by type, olive oil should be golden-green to golden-yellow. Cloudiness, sediment, or separation all signal spoilage, especially if combined with bad smell or taste.

How Long Does Olive Oil Last?

Unopened: up to 18–24 months from bottling
Opened: best used within 6–12 months

Harvest Date: Olive oil starts degrading the moment the olives are harvested. So, check the harvest date (if available) in addition to the best-by date on the bottle, and then compare that against the purchase date.

Storage Matters: How you store your olive oil greatly impacts its shelf life. Olive oil hates sunlight, moisture, heat, and cold. As such, purchase olive oil that is either in metal tins or dark glass bottles (plastic bottles sap flavor). Then, store them in room temperature, dark areas – such as in a kitchen cabinet, or in the pantry. Never store olive oil unsealed.

How to Store Olive Oil to Keep It Fresh

Store it in a cool, dark place (away from the stove).
Use a dark glass or tin container to further limit light exposure
Seal tightly after each use
Avoid frequent opening and closing of large bottles. This is why I recommend using smaller dispensers

Bonus Tip – For Pros and Enthusiasts

Learn the taste of your favorite olive oils. Do this by tasting the oil raw, either on a spoon or a piece of plain, crusty bread or pita. That way, if you’re not sure if your olive oil has gone bad, you can simply taste it and tell right away if it’s gone bad or not. This is the quickest and surest way to tell.

And that’s my answer to whether or not your olive oil has gone bad, and how to tell.

Happy Cooking!