Cooking Oils
By Tiffany Joy Yamut, BSN, RNNovember 12th, 2024

Does Olive Oil Go Bad?

Learn how to tell if olive oil has gone bad, how to store it, and explore an alternative with a longer shelf life.

Key Takeaways:

  • Over time, olive oil loses its freshness, flavor, and nutritional value due to exposure to light, heat, and air, and may eventually turn rancid.
  • Bad olive oil may smell sour, musty, or waxy, taste bitter or stale, and appear cloudy or darker in color.
  • If you need a milder option or are out of fresh olive oil, algae oil can be an excellent choice. It has a shelf life of 2 years.

Olive oil is a favorite in many kitchens for its rich flavor and health benefits. People often save olive oil for special Mediterranean dishes, as its unique taste adds something extra to meals like salads, grilled vegetables, and pasta.

If you're a fan of this versatile oil, you may find yourself wondering: does olive oil go bad? The last thing you want is to use expired oil in your carefully crafted dish, but how can you tell if it’s still good to use?

While olive oil is perfect for many dishes, it may not always be the best choice depending on the flavor profile you're aiming for. So, if you find yourself out of fresh olive oil, or need an alternative for a milder taste, you may need an alternative for a milder taste.

Find out what happens when olive oil expires, how to properly store it to extend its shelf life, and a perfect substitute.

Does Olive Oil Go Bad?

Yes, olive oil can go bad. Over time, it loses its freshness, flavor, and nutritional value and may eventually turn rancid. This happens because olive oil is sensitive to light, heat, and air, which can cause the oil to break down and spoil .

Extra virgin olive oil (EVOO) generally has a shorter shelf life compared to regular olive oil because it undergoes less processing and retains more of its natural compounds, which makes it more delicate and prone to spoilage.

The age of the olive oil also matters. Most bottles will have a “best by” date, but olive oil doesn’t spoil immediately after that date — instead, it gradually loses its quality.

Related Article: Avocado Oil vs. Olive Oil: Differences & Alternatives

How Long Does Olive Oil Last?

How long olive oil lasts depends on the type of olive oil. An unopened bottle of olive oil can last between 12 to 18 months if stored properly, but once you open it, the oil starts to degrade as it gets exposed to air, light, and heat.

For the best quality, it’s recommended to use olive oil within 6 months of opening, as this is when it will be freshest and have the best flavor and nutrients. After this time, the oil starts to lose its vibrant flavor, and it may become less rich and more bland.

EVOO, being less processed, has a shorter shelf life after opening and is best used within 3 to 6 months to enjoy its peak freshness and flavor. If kept for too long, EVOO can develop a rancid or bitter taste.

Related Article: Olive Oil Smoke Point

How Can You Tell If Olive Oil Has Gone Bad?

You can tell if olive oil has gone bad by its smell, taste, and appearance:

  • Smell. Fresh olive oil has a mild, fruity aroma that reminds you of fresh olives, grass, or herbs. On the other hand, olive oil that has gone bad smells sour, musty, or similar to crayons (which may be described as a “waxy” scent).
  • Taste. Fresh olive oil has a smooth, rich taste with a balance of fruity, peppery, and slightly bitter notes. When it’s gone bad, it will taste bitter, stale, or flat.
  • Appearance. Fresh olive oil has a clear and golden or greenish color depending on the type of olives used and their ripeness. Bad olive oil may look cloudy or develop a dark color. Also, watch out for a thicker texture, which may signal that the oil has started to break down.

If you notice any changes in smell, taste, or appearance when assessing your olive oil, it's wise not to use it. It would be safer to discard the oil.

What Happens If You Use Expired Olive Oil?

Using expired olive oil isn’t usually harmful in the short term, but it can affect the flavor and quality of your food. As olive oil ages and oxidizes, it loses its desirable qualities, which may negatively affect the taste of your dish.

For example, if you use expired olive oil in a fresh salad dressing, the once bold, peppery flavor can turn flat and rancid, which ruins the freshness of the vegetables.

Expired olive oil has lost its nutrients, so you won’t get the same benefits as you would from fresh oil. Regularly using rancid oil can also lead to the buildup of harmful compounds, like free radicals, which may negatively impact your health over time. A study published in Food and Nutrition Sciences discusses how rancid oils generate free radicals, which are known to cause cellular damage .

How to Properly Store Olive Oil

To get the most out of your olive oil and make sure it stays fresh for as long as possible, proper storage is key. Follow these tips:

  • Store it in a cool, dark place. Keep olive oil away from heat and light, which can cause it to spoil faster. Olive oil should be kept in a temperature-controlled environment, ideally between 57°F and 70°F (14°C to 21°C).
  • Seal it tightly. Every time you open the bottle, air enters, and prolonged exposure to air can cause the olive oil to oxidize and go rancid. Minimize this by making sure the bottle is tightly sealed.
  • Use a dark container. Opt for dark glass bottles since they effectively block out harmful UV rays that can degrade the oil. Research shows that even small doses of radiation can cause noticeable changes in olive oil .
  • Control humidity. Store olive oil in a dry area as excess humidity can cause moisture buildup and promote spoilage. Keep it away from environments like kitchens near stoves or dishwashers.

The Bottom Line

Olive oil can be a valuable ingredient in your kitchen, but like any natural product, it has a shelf life. Proper storage keeps olive oil fresh and vibrant for as long as possible.

If you're out of fresh olive oil or need a milder option, algae oil is a great alternative. It has an impressive shelf life of 2 years — and with a neutral taste, algae oil works well in many dishes. Plus, it's packed with heart-healthy omega-9 and is a cleaner, more eco-friendly choice!

By Tiffany Joy Yamut, BSN, RN
Health & Nutrition Writer

Tiffany Joy Yamut is a registered nurse with a focus on health and wellness. With over 10 years of writing experience, she combines her expertise in diet and nutrition coaching to help others adopt healthier lifestyles through balanced eating habits. A foodie at heart, Tiffany believes that food is essential to feeling your best.