Does Olive Oil Go Bad? How to Tell Olive Oil Is Rancid

There are a few ways you can tell if your olive oil has gone bad:

• Taste: This is the best way to determine whether your oil has gone rancid. A small taste is fine and won’t cause you harm. Olive oil that has turned rancid may have the following characteristics:
  • May taste bitter, sour, or stale
  • May have a crayon-like taste
  • Leaves an unpleasant residue on your tongue
• Smell: Fresh olive oil typically has a bright, fruity, and pleasant odor, whereas bad olive oil may smell like crayons, putty, or Elmer’s glue.

Rancid oil will not necessarily make you sick, but it can ruin a dish as well as lose some of its antioxidant properties. Therefore, in order to maximize the nutritional benefits of olive oil, it is best to consume it fresh.

Olive oil does not have an expiration date due to the following reasons:

• If stored properly, olive oil can retain its properties for a long time
• Most of the nutritional aspects of olive oil are not lost when stored correctly

Although olive oil does not have an expiration date, it should have a best-before date. The best-before date is usually between 9 -24 months from the date of manufacturing. Extra virgin olive oils are less processed and have a best-before date of 12-18 months from the time they are bottled.

Although consuming olive oil after the best-before date is completely safe, there is no guarantee that the product will retain the same organoleptic (taste, odor, and smell) properties it had at the time of bottling. Beyond these time frames, olive oils tend to develop an acrid or bitter taste.

Exposure to light and heat can turn olive oil rancid. Therefore, it is important to purchase olive oil that comes in dark glass bottles.

Avoid buying oil that has been sitting on the shelf for many months. Once you bring it home, store it in a cool, dark place and only open it before you are ready to use it.

Storing olive oil between 55-60 F can help prolong its shelf life. Here are some tips for storing olive oil properly:

• Store it in a cool, dark place, such as a pantry with a door, a cabinet, or a refrigerator (if stored in a refrigerator, it may turn cloudy, which is quite normal)
• Cap the bottle tightly after opening it
• Transfer your oil to a dark glass or tin container if it comes packed in a plastic polyethylene container