Once the vegetable oil has completely cooled, you can strain it through a sieve and store it in a sealed container in a cool, dark place. You can then reuse it a few times – cooling and sieving as described after each use – as long as it smells fresh, doesn’t start to smoke easily on heating, and the colour doesn’t darken.
To dispose of large quantities of cold cooking oil, take it to a recycling centre to recycle (check your local centre accepts cooking oils), or put it in a sealed container and place it in your general waste bin. Do not pour it down the sink.