Does Vegetable Oil Go Off?

A question we get asked often is, ‘Does Vegetable Oil Go Off?’ and that got us thinking about how long vegetable oil lasts and how you should store it to slow down the rancidification process. So, does vegetable oil go off? 

Yes, vegetable oil does go off. Expired vegetable oil can make you seriously sick after it breaks down. The rancidification process speeds up as soon as the oil has been opened, so it’s essential to store it correctly, especially if you are going to reuse it. You should be aware not to overuse vegetable oil as it can cause severe health conditions and increase the risks of trans fatty acids in your food. 

Read on to learn more about how vegetable oil goes off and how to store your oil with BioUKFuels. 

How Long Does Vegetable Oil Last? 

Vegetable oil lasts for twelve to eighteen months once it’s been opened.  Vegetable oil often has a best-before date rather than an expiration date. If you use your vegetable oil after its best-before date, it won’t be at its peak, but it is still usable. If you’ve noticed the signs the oil has gone off, such as darker colour and foaming on the surface, then it’s time to dispose of it. 

If your business needs to dispose of your vegetable oil and have a lot stored, why not get in contact with us for free removal with a licensed waste carrier? Alternatively, check out our post on ‘How Do You Dispose Of Use Cooking Oil’ for more information and advice. 

How Do You Tell If Your Vegetable Oil Has Gone Off? 

There are some clear signs that your vegetable oil has gone off. These include: 

  • Sharp taste, leading to lower quality taste in cooked foods. 
  • Strong, unpleasant odour. 
  • The oil will start to burn before it reaches its original smoke point. 
  • Discoloured, cloudy appearance. 
  • Thicker than usual.
  • Has a foamy film on the surface. 

When you notice any of these signs, it is best to dispose of your oil and open a new batch. Contact us today for free collection and disposal of your vegetable oil from your business. 

How To Store Your Vegetable Oil? 

Your vegetable oil should be stored in a cool, dark and dry environment to prevent the oil from being affected by oxidation. Heat exposure also affects vegetable oil, causing it to break down and possibly turning it rancid.

If you’re looking for more advice on how to store your vegetable oil, read our in-depth blog, ‘What Is The Proper Way To Store Oil?’ 

How To Store Used Vegetable Oil? 

Once you’ve finished using your vegetable oil, you can preserve it to be used again. Firstly, you should allow the oil to cool completely. Before you store your vegetable oil, it needs to be at room temperature to protect the storage container from damage and yourself from burns. 

Next, you need to strain the oil through a fine mesh strainer with a protective layer, such as a kitchen roll or a coffee filter. This will catch any leftover pieces of food or particles from your previous frying, as when you reuse the vegetable oil, those particles will burn, giving an unappetising overcooked and greasy taste to your food.

After the vegetable oil has been strained, it must be transferred to a clean container and stored in a cool, dark place. If your vegetable oil isn’t cooled or stored correctly, the oil case poses a serious health risk

How To Dispose Of Used Vegetable Oil? 

When you dispose of your used vegetable oil, there are practices that you need to follow to meet food safety standards. You cannot pour used vegetable oil down the drain or sewers as it will cause blockages and damage to the local wastewater mains. Professional and domestic licensed services will collect your used vegetable oil for disposal. 

For Business Use 

When disposing of vegetable oil commercially, there is only one legal way to do this. As a legal and environmental requirement for working in the food sector, you must dispose of your used vegetable oil. 

You can do this with a licensed waste collection service so the work is done for you. Contact us here at BioUkFuels via our contact form or call us at 01709 373248, select your collection date, and store your used vegetable oil ready for collection. This can be done in either the containers they came in or the ones we have provided.

For Domestic Use 

You can do this two ways when disposing of your used vegetable oil domestically. Firstly, you can contact a waste disposal service to collect your used vegetable oil. You should store your oil in either the containers they came in or leakproof containers that do not spill and are ready for collection. 

The alternative is to see if your local recycling accepts used vegetable oil and will dispose of it for you. Check with the Recycle Now website if your local recycling centre takes used vegetable oil. 

Collecting Your Used Vegetable Oil 

At BioUKFuels, we help your business recycle your used vegetable oil across the UK. We offer free waste collection services where we collect your used vegetable oils and fats. They’re then converted into biodiesel, our contribution to renewable fuel. To schedule a free collection that suits your business needs, simply call us at 01709 373248 or complete our online contact form to learn more about our services.

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Bio UK Fuels (Sheffield) Ltd
Unit 6A
Greasbro Rd, Tinsley
Sheffield, S9 1TN


01709 373248



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