How to Clean Frying Oil
Straining fry oil will allow you to reuse it multiple times.
If there is a downside to deep frying, it’s the large quantity of oil that's often required. But unless the oil was overheated and started to smoke, which degrades the quality, or you used it to fry fish, it's fine to reuse it once you strain it. Here are two easy ways to clean used frying oil.
How to Strain Frying Oil with a Coffee Filter
This hands-off method takes a while and can leave the oil with a slightly “used” taste, but it is the simplest.
Line a fine-mesh strainer with a coffee filter and place over large container.
Pour oil through the filter and allow to drain (this may require several additions of oil). Discard solids.
How to Strain Frying Oil with a Cornstarch Slurry
Adding cornstarch to the oil, which attracts and traps solids for easy removal is the quickest way to clean fry oil and leaves the oil tasting clean.
1. For every cup of frying oil, whisk together ¼ cup water and 1 tablespoon cornstarch.
2. Add mixture to warm or cooled oil.
3. Heat oil gently over low heat (do not let it simmer), stirring constantly with heatproof spatula, until starch mixture begins to solidify, 10 to 12 minutes.
4. Remove oil from heat and strain through fine-mesh strainer (or use slotted spoon to fish out gelled mixture). Don't worry if oil appears cloudy; it will clear up once reheated.
Can You Reuse Frying Oil?
Yes, but how many times you can reuse oil depends on what you’re frying: Battered or breaded foods like chicken will degrade oil faster than cleaner-frying items like potato chips. But the oil from both can be reused at least three times, and in some cases you can reuse oil eight or more times. When the oil is brown, smokes easily, and has a greasy odor, it's time to pitch it.