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Does Cooking Oil Ever Go Bad? What To Look Out For

Cooking oil is an important part of many of our daily lives. We need it to do most of our cooking, and so much more.

However, one question that many people have is about whether cooking oil can go bad or not. In short, cooking oil can eventually go bad, like other food items. 

When we are talking about cooking oil, we are referring to a wide range of oils that we use for cooking.

Does Cooking Oil Ever Go Bad What To Look Out For

This can include vegetable oils, olive oils, and anything else you can imagine.

All of these oils can go bad, but they have different shelf lives, depending on what they’re made from. 

If you want to find out more about cooking oils going bad, just keep reading! We will be going through everything you need to know about it right here. 

Can Cooking Oil Go Bad?

Quick Answer: Yes – cooking oil can go bad. The speed that this will happen is determined by a couple of things, though.

The method of storage, overall oil composition, and even how refined it is will play a part in this, not to mention what it’s made from. 

Generally speaking, oils such as safflower, sunflower, olive, canola, and blended vegetable oils can last a while. If unopened, these oils should last for around two years.

Once opened, however, you can expect them to remain good for about a year, providing it’s stored properly. 

Other oils, such as sesame, corn, and a number of nut oils, are more delicate. They will typically only last around one year when left unopened.

Once you open them, however, expect them to last between 4-9 months if they’re stored properly. 

Because of their short shelf life, these more delicate oils should be used up pretty quickly.

It’s better to simply use them rather than forget about them and end up with something you can’t use when you eventually need it. 

What To Look Out For

If your cooking oil goes bad, you won’t notice the same signs of spoilage like other food. There won’t be any rot or mold.

The one thing you will need to keep an eye out for is the rancid smell – it will be strong and unpleasant. 

Always check for this unpleasant smell before using it. Ingesting even a small amount of rancid oil can have unpleasant side effects, and it can lead to long term health issues.

This rancid oil will have a negative impact on the taste of your food. 

If you refrigerate your oils, you might notice that they have solid bits and appear cloudy. It’s important to note that these signs do not mean that the oil is rancid.

You can still use this oil as long as it doesn’t smell bad. If the appearance of this oil bothers you, simply leave the oil out to reach room temperature before use. 

It’s natural for some oils to turn cloudy or even solid when exposed to cooler temperatures. This is especially the case of olive oil.

If you notice this, don’t assume the product is spoiled and unfit for use. Always do the smell test before throwing it away.

Storing Cooking Oil Properly

Unopened oil should be kept in a cool, dark place, and in a tightly sealed container. Keep it away from heat and direct light to extend the shelf life of the product.

When you eventually open the oil, it should always be resealed and refrigerated if possible. This won’t extend the shelf life past a year, but it will prevent it from spoiling prematurely. 

You shouldn’t attempt to freeze oil to extend its shelf life. In fact, once frozen oil thaws, it typically spoils faster due to the structural changes that occur. 

To make sure you’re getting oil that will last, look for bottles that are either dark or opaque.

However, the majority of commercial cooking oils are kept in clear plastic bottles, so this might not be possible. The packaging of most bottles only means that proper storage is very important. 

You should also always check the dates printed out on bottles. Try to stick to oils that have at least one year of shelf life remaining.

If you don’t, you might end up with a bottle of oil that will go rancid in only a few months or even weeks.

Jess Smith