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If you want to be able to reuse your cooking oil, it's important that you start off with a cooking oil that is worth reusing. Choose a cooking oil with a high smoking point this is the temperature at which the oil starts to break down. A higher smoking point means your cooking oil will last better under higher temperatures and will be more reuseable. Try using canola, vegetable, or peanut cooking oils. Avoid using olive oil, as it has a low smoking point, and doesn't readily lend itself to reuse. Don't try to store your used cooking oil until it has completely cooled off. As soon as you are finished using the oil, turn off the heat source and let the oil sit (overnight if necessary) before you try to transfer it into a container for storage. If you leave the oil out overnight, be sure to cover it with something to keep it from getting inadvertently contaminated. Whenever you use cooking oil, there will always be something left behind that you don't want to leave lying around in the oil. This might include breading crumbs, loose batter, or extra fat. To get rid of these extras, you can filter them out by running the oil through a cheesecloth. Make sure you place the cheesecloth on top of a clean container that can hold the filtered oil. Pour the oil onto the cheesecloth and let the clean oil spill into the new container. This will help you avoid making a big mess. Remember to never pour cooking oil down the drain. This can cause clogs and other damage to your pipes over time.
Choose a cooking oil with a high smoking point. Let the oil cool. Filter out the unwanted leftovers with cheesecloth. Place the cheesecloth over a clean open container.