Why can’t we keep reusing cooking oil for frying?

Question

I tried searching for a good answer on Google but none came.

In: 2

Answer 1

Who says we can’t, I keep old frying oil and reuse it. As long as it’s not an animal fat, in which case you have to refrigerate it. However if you’re asking why we don’t use it after it goes dark and burnt it’s because it no longer tastes good, eventually the residue from all the foods cooking in it builds up and makes it taste burned and makes all the other food you cook taste like it.