How To Tell If Cooking Oil Is Bad?

bOil, like salt, wheat, and those too-sweet rainbow popsicles in your freezer, is one of those items we don’t think has an expiration date, but it won’t last forever like anything fresh. Always check for rancidity in your oil before using it. Rancid fat can cause intestinal discomfort and give your food a bad taste in a short period. It is not suggested to consume rancid oil because it might harm your health in the long run.

Cooking Oil

Although those glass olive oil containers you see on restaurant tables may appear more admirable than the bottle or tin your oil came in, if they’re made of clear glass, they won’t help increase the shelf life of your oil.

The oil that hasn’t been opened and kept in a dry, relaxed environment can survive up to two years. “The first two to three months after opening the oil should be spent using it. A well-made and high-quality product, on the other hand, could last up to a year if stored in a dry, cold location with the lid well secured.”

How To Tell If Cooking Oil Is Bad?

Cooking oils will not grow mildew or rot but eventually go wrong. Here Are Some Signs Of Bad Cooking Oil:

  • Rancidity is the most evident symptom when cooking oil has gone wrong. Oils that have been refrigerated may turn hazy and harden slightly, but this does not indicate that they have gone wrong.
  • The stench of rancid oil is pretty strong and unpleasant. Set the oil out at room temperature to revert to a liquid condition. Certain oils, such as olive oil, may have sediment when stored at lower temperatures.
  • However, this is only a reaction to the cooling and does not suggest deterioration. Unrefined oils, such as extra-virgin olive oil, are more challenging to work with.
  • They have scents and flavors that might hide rancidity, making it difficult for non-experts to tell if they’re rancid simply by smell.
  • As a result, it suggests giving the oil a try. Pour some into a cup and warm it in your palms to bring the oil to room temperature.
  • Suck on a bit of liquid (approximately a teaspoon) as if sucking juice through a straw without swallowing or exhaling.
  • Because this flavor is difficult to define, Decker advises tasting—and smelling—any oil the first time you open the jar to establish a baseline.
  • This method is advantageous when it comes to olive oils. If it’s rotten, the combination of the olive oil flavor and the rancidity odors will give it an off-tasting.
  • Finally, rancid oils can get sticky, so it’s probably time to throw them out if the container feels tacky around the spout.

When It Comes To Vegetable Oil, How Long Does It Last?

Soybean oil, sunflower oil, and peanut oil are a few examples of vegetable oils. Their shelf lives, on the other hand, are very comparable. If you keep your vegetable oil sealed and well stored, it should last at least two years, if not much longer, and the oil in the bottle should last at least a year after you open it.

You can keep vegetable oil from going wrong for a more extended time, even much longer, if you store it properly. Another point worth mentioning is that the oil flavor varies over time, and you may not be pleased with those changes, particularly if you want to use the oil in a salad and it starts to smell bad.

A few notes on vegetable oil storage. First and foremost, keep in mind that vegetable oil should be stored in a cold, dry environment. It’s common to keep it in the pantry, and it’s a brilliant idea. On the other hand, refrigerating vegetable oil is not a good idea. Holding, the bottle out of direct sunlight, is also a good idea, so stashing it in the pantry cupboard is the best option.

Finally, once you’ve opened the bottle, ensure it’s appropriately sealed while not using the oil. When oil is exposed to fresh air regularly, the oxidation process begins, causing the oil to degrade more quickly. There will be no pollutants or stand in the bottle due to this.

Does Vegetable Oil Have A Shelf Life?

Vegetable oil, in reality, has a shelf life. Even if it is well stored, it will ultimately occur. However, going wrong isn’t always a concern because vegetable oil typically goes terribly after a long period.

As I mentioned above, the flavor of oil changes over time. So after a few years, the oil will not be of good quality. Even if it’s not rancid, you’ll probably decide to discard it because it’s rancid.

Vegetable oil can become deficient in several instances, but they are pretty unusual. How can you know if it’s terrible? Examine its appearance, smell, and taste, and you’ll quickly recognize it. If you find that its color has changed (it is now dark), developed an unpleasant odor, or tasted off, throw it away.

What Is The Best Way To Store Cooking Oil?

Cooking oil that has not been used should be stored in a tightly shut container in a cool, dark environment. By keeping the oil out of light and heat, its shelf life will be increased as much as feasible. Even if the oil’s shelf life will remain one year, refrigerate the tightly closed container. It will prevent it from going rancid for as long as possible after opening it.

It should not be frozen to increase its shelf life. Freezing the fat will not raise its shelf life and hasten the spoilage process once it thaws. Because freezing and thawing can alter the structure of the oil, it will oxidize more quickly and turn rancid. When buying a bottle of cooking oil, look for one stored in a dark glass or opaque container.

By blocking away light, the fat will not spoil as soon. Of course, because many cooking oil brands come in clear plastic containers, it’s critical to preserve the bottle correctly once you get home. Check the dates on the bottles and try to buy oil with at least a year left on its shelf life. This ensures that you get the most out of your oil bottle.


“It may start to turn sour or unusually harsh,” explains Laurence Edelman, chef and proprietor of the Left Bank restaurant in New York. “But, honestly, you don’t have to worry about how long it lasts if you use it quickly!”

Use the general rule of thumb for food safety: If in doubt, throw it out if you think your oil is bad. While using expired oil won’t likely result in death or illness, you should stop buying oil in large quantities if you want your food to have the optimum flavor. Instead, purchase what you require at the time.