How to keep my (deep frying) oil usable as long as possible?

Question

I have a new deep fryer. I am pleased with its results so far. I am not a 'heavy user' though - say once every 2-3 weeks. I want to re-use the oil a couple of times. The deep fryer is covered but not airtight, however.

The new deep fryer has a cold zone, which means the oil won't become dirty due to particles over-frying. I don't overheat the oil either. So, in principle, I'm frying correctly, I think.

So, how long can my oil safely sit in the deep fryer, if I ensure it's thouroughly heated next time I fry? Should I be allowing the oil to cool and store the fat in (sealed) containers instead, if there's going to be this long a gap between uses?

Edit: yes, I've seen this question and answers: http://cooking.stackexchange.com/questions/3014/frying-oil-reuse

Asked by Tobias Op Den Brouw

Answer

First thing, a cold zone doesn't prevent particulate build up, it just cuts down on the amount that will remain suspended in the oil. You should still filter if you want to keep your oil as long as possible. You can detect bad oil (meaning rancid) by a few ways, like smoke point or smell.
You should store your oil someplace dark and cool, which could be the inside of your fryer as long as you filter and clean the sides before you stick the oil back in. Another thing you can do to extend the life of your oil is switch to tallow (beef fat) or rended pigs fat (lard) as saturated fats do last a lot longer than the poly-unsaturated.

Once again, you should lose the oil when the smoke point drops, or if it is to dark, or if it develops any foul odor. And as I said before, once you use the oil once, you should NOT use it past six months under any circumstances, if you do, you are taking your gastro-intestinal tract into your own hands.

Answered by sarge_smith

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