Why is it bad to reuse oil?
Reusing of the same oil repeatedly has been found to lead to the generation of free radicals. Free radicals can lead to inflammation, cardiovascular diseases and even cancer. Reusing oil can also lead to atherosclerosis that can cause an increase in bad cholesterol, leading to a blockage in arteries.
Our recommendation: With breaded and battered foods, reuse oil three or four times. With cleaner-frying items such as potato chips, it's fine to reuse oil at least eight times—and likely far longer, especially if you're replenishing it with some fresh oil.
A consequence of frying with over-used frying oil is the more degraded it is, the higher the absorption of oil by the food. This leads to dark, soggy food on the plate. Not a good look!
You can't drain the old oil out of your vehicle and then put it back in. Recycling engine oil means sending the used motor oil to a recycling facility. The recycling facility will recycle the motor oil into something else.
It is believed that thieves are targeting businesses such as takeaways and pubs, to steal the used oil to sell on to make biofuels for use in diesel vehicles.
Beyond that, oil can be reused by letting it cool, straining it through a fine mesh strainer, coffee filter or several layers of cheesecloth, and then storing it in a dark place to fry another day.
Olive oil and avocado oil are good choices for deep frying. Peanut and palm oils are less suitable, either for health or environmental reasons.
Yes, it is OK to reuse fry oil.
The repeated reheating of cooking oil changes its composition and releases acrolein, which is a toxic and potentially carcinogenic chemical. Restaurants and other food outlets often reuse soybean oil multiple times before replacing it with fresh oil in the frying vats.
Simply pour a small amount into a spoon and give it a quick sniff. If it has an “off” odor—perhaps like crayons, metal, or something sour—it's past its prime. To see if olive oil is past its prime, pour some into a spoon and sniff it. Sour odors mean that it's rancid.
How long can you keep oil after frying?
“How long does oil keep in the deep fryer?” Oil loses a lot of its virtues if it is more than six months old. Most oils should be changed after eight to ten uses. You need to remove oil from the deep fryer after each use, strain it and store it correctly until the next time.