Does Peanut Oil Go Bad?

Peanut oil is an item we keep in our kitchen for occasional use. Since we don’t use it every day, we may ask ourselves the next time we reach for it, does peanut oil go bad?

Peanut oil can go bad.

  • Like the vegetable oils in our kitchen, peanut oil has a best by date that we should adhere to.
  • An unopened bottle of peanut oil will approximately last 1-2 years after its best by date.
  • An opened bottle of peanut oil will approximately last 6-12 months.
  • Used peanut oil will approximately last 2 weeks.


Peanut oil tastes best when we use it within its expiration date. Proper storage and refined peanut oil will last the longest in our kitchen.

Does Peanut Oil Go Bad? How Long Does Peanut Oil Last?

Peanut oil is used for frying, baking, and cooking in many cuisines, such as American, Chinese, African, Indian, and Southeast Asian. Peanut oil adds a nutty flavor to dishes.

Peanut oil can go bad. When oil goes bad, we refer to it as rancid. It is best if we follow the best by date on the bottle for the best taste. An unopened bottle will last about 1-2 years after its best by date. However, an opened bottle will last about 6-12 months. If you use peanut oil, it will last only approximately 2 weeks.

Peanut oil is extracted from peanut kernels. The manufacturer places the kernels into an expeller, which presses and extracts the oil. A screen separates the oil from the kernels. Next, solvent extraction separates the remaining oil from the kernel.

Cold-pressed peanut oil is healthier than hot-pressed peanut oil. Cold-pressed peanut oil is simply made by extracting the oil from the peanut kernels at room temperature. Cold-pressed oil has low acidic values, which means manufacturers do not need to refine it. Cold-pressed peanut oil is healthier than hot-pressed peanut oil because it does not involve treating the kernels with chemicals.

Hot-pressed peanut oil lasts longer than cold-pressed peanut oil. Manufacturers roast the kernels before extracting the oil. During the roasting process, manufacturers add chemicals to the kernels. Before we can consume it, manufacturers refine the peanut oil. It is necessary to refine the oil because the chemicals cause the oil to be high in acid. Although hot-pressed oil will last longer since it is refined, it is not as nutritional as cold-pressed peanut oil. However, consumers prefer hot-pressed peanut oil due to its stronger aroma.

Peanut oil has health benefits.  Peanut oil is high in vitamin E, which is an important antioxidant for your body. Peanut oil also has one of the highest levels of monounsaturated fats in comparison to other vegetable oils. Monounsaturated fats improve blood cholesterol levels, which could reduce your risk of heart disease. If you are striving for the healthiest option, cold-pressed peanut oil has more health benefits than hot-pressed peanut oil.

If you store peanut oil properly, it will maximize the oil’s shelf life. Knowing how long peanut oil will last outside, in the fridge, or freezer will help you make the best choice of where to keep it.

How Long Does Peanut Oil Last Outside?

You can keep peanut oil outside if you plan to use it periodically.

Peanut oil will last for 1-2 years beyond the expiration date if kept outside in an unopened bottle. Simply keep the peanut oil in the store-bought bottle until you are ready to use it.

If you open the bottle of peanut oil, it will last 6-12 months outside. Close the bottle tightly in between uses to prolong its shelf life.

Lastly, if you use peanut oil, it will last about 2 weeks. Do not pour the used oil back into the bottle with the unused oil.

How Long Does Peanut Oil Last in the Fridge?

If you use peanut oil infrequently, you should store it in the fridge. The fridge can extend the shelf life of peanut oil.

Unopened peanut oil will last 3-4 years in the fridge. If you have a large quantity of peanut oil that you do not plan to use for a while, the fridge can extend the oil’s shelf life. The oil may thicken and turn cloudy in the fridge, but this will not impact the quality.

The fridge will extend opened peanut oil’s shelf life by a few months. An unopened bottle of peanut oil will last 6-12 months, and storing it in the fridge could add a few months to that. But you should evaluate it before use to ensure it is still good.

Used peanut oil can last up to 3 months in the fridge. Transfer the used oil from the fryer or pan to an airtight container.

How Long Does Peanut Oil Last in the Freezer?

Similar to the fridge, the freezer will preserve peanut oil but not indefinitely.

Peanut oil will last for about a year in the freezer. One year in the freezer is a standard timeframe for unused or used peanut oil. The freezer may alter the taste and aroma of peanut oil.

Peanut oil’s freezing point is 37 degrees Fahrenheit. Most of us keep our fridge at or below 40 degrees Fahrenheit. Depending on your fridge’s temperature, your peanut oil may freeze in the fridge.

It is important to note the date of when placing the oil in the freezer to ensure you use it before it becomes rancid. Purchasing peanut oil only once a year can save money.

Peanut oil has a long shelf life. Knowing how long peanut oil will last outside, in the fridge, and the freezer can save you from buying it more often than necessary.

How to Tell if Peanut Oil Is Bad and How To Know if Peanut Oil is Fresh

Since we can store peanut oil for a long period, we need to be able to determine if it is bad or fresh.

All oils eventually go rancid. There are 3 ways to determine if your peanut oil is bad.

Darker color: The color of peanut oil depends on whether it was refined or not. If your peanut oil has become a darker shade than it was when you purchased it, this is a sign it is bad. The color may darken after use, but if it is much darker, it is likely bad. If you are unsure, a taste or smell test can help you determine if it is still good.

Wine taste: Rancid peanut oil will taste similar to fermented fruit or wine. At this point, it is time to throw it away.

Smell: If the peanut oil has a sour smell, it is rancid. It is best to throw away peanut oil with a bad smell.

You can use the same 3 tests to determine if peanut oil is fresh.

Color: Unrefined peanut oil is typically a darker shade of brown. Refined peanut oil resembles more of a yellow color. If your peanut oil is one of these colors, it is likely fresh.

Taste: Fresh peanut oil should have a light, nutty taste.

Smell: Fresh peanut oil usually has a neutral smell.

How to Store Peanut Oil

Depending on how often you will use peanut oil will determine the best storage for it.

Store peanut oil in a dark, cool place away from heat and light. If you plan to use your peanut oil periodically, store it in your cupboard in an airtight container. Choose a cabinet that is away from the oven and windows. Heat can decrease peanut oil’s shelf life. Also, choose a cupboard that closes. This will protect it from light.

Store peanut oil in the fridge in an airtight container. If you will use your peanut oil infrequently, the fridge will preserve it longer. You should also store used peanut oil in the fridge to preserve freshness. Before using the refrigerated peanut oil, allow it to sit at room temperature to fully liquefy. It is important to note when you put the peanut oil in the fridge to ensure you use it before it becomes rancid.

Can You Freeze Peanut Oil? How?

Yes, you can freeze peanut oil. Freezing peanut oil is only ideal if you buy it in bulk.

Although you can freeze peanut oil, it is not the best storage option. People like to use peanut oil for its flavor. When you freeze peanut oil, the flavor may not be the same.

Divide the peanut oil into smaller portions before freezing. By freezing smaller portions in an airtight container, the thawing process will be easier. Also, use an airtight container to prevent freezer burn. Light-resistant plastic fares best in the freezer. Don’t fill the container to the top as the peanut oil will need room if it expands.

Similar to refrigerating peanut oil, it is best to note the date when placing it in the freezer. This is important as it is more difficult to determine if the peanut oil is rancid after storing it in the freezer.

How to Thaw Peanut Oil

Remove the peanut oil from the freezer when you are ready to use it. If you will not use the peanut oil right away, you can allow it to thaw at room temperature. The cloudy peanut oil will return to its natural liquid state.

If you want to use the peanut oil right away, you can use the microwave or heat it in a pan on the stove.

Frequently Asked Questions About Peanut Oil’s Shelf Life

Can I make my peanut oil? Yes, you can make peanut oil at home. First, remove the shell and skin of the peanuts, and wash them. Second, soak the peanuts for 10-15 minutes in warm water. Third, blend the peanuts in a blender to make a paste. Fourth, transfer the paste into an airtight container and store in the fridge for at least 24 hours. Fifth, use a colander to separate the oil from the paste. Sixth, store your homemade peanut oil in an airtight container.

When should I cook with peanut oil? Dishes that require frying or sauteing pair well with peanut oil. Peanut oil has a high smoke point. This is important for frying food as the oil can withstand high temperatures. If you use an oil that has a low smoke point, the oil will smoke and impact the flavor of the dish. Peanut oil is also great for frying as it does not absorb the food’s flavor. This will allow you to use it multiple times.

Can I get sick from rancid peanut oil? Yes, rancid peanut oil can make you sick or impact your long term health. Rancid oil develops dangerous free radicals that harm the health of your cells. Cell damage has been linked to Alzheimer’s disease and diabetes. Consuming rancid oil can also cause digestive system issues. Lastly, rancid oil can affect your body’s vitamin E and B levels.

Wrap Up

Peanut oil is a great addition to your kitchen, especially for frying, and sauteing. If we store peanut oil in an airtight container in a dark, cool place or the fridge, we can extend its shelf life.

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