Dear Lifehacker, The oil in my deep fryer needs replacing. Rather than throw out the oil, is there a way to repurpose it? Thanks, Chiptastic
The question of just how long you can keep using the same oil in a deep fryer before you have to replace it has always been contentious amongst cooks. Nonetheless, there inevitably comes a time when it's time to drain the deep fryer, and that leaves you with a substantial quantity of mildly unpleasant liquid.
Don't be tempted to pour it down the sink: you'll pollute the waterways and quite possibly block your sink in the process. If you're just looking to get rid of it, wait for it to cool, pour it into a disposable container (a milk carton is a popular choice) and pop it in the rubbish.
That might seem wasteful, but there aren't too many obvious alternative uses accessible to home users, with one big exception: composting. If you have a compost heap, you can add used vegetable oil quite safely. (The same isn't true of animal fats; check out this handy list from Clean Up Australia for more details on what you can and can't compost.)
There are anecdotal accounts online of people passing on their oil to farmers for use in feed and commercial operations which repurpose oil to produce biofuels, but both options are more realistic for restaurants and takeaway food joints than for individual cooks. (If you're producing industrial quantities of used deep fryer oil, it's time to look at your diet.)
If readers have additional hints on what to do with household quantities of used deep fryer oil, I'd love to hear them in the comments.
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