1/2 cup water
1 tsp. gelatin
1 qt. frying oil

  • heat water and mix in gelatin to dissolve
  • pour into used frying oil
  • mix well and cover
  • chill overnight and pour off clarified oil
  • discard congealed gelatin with impurities

source: https://www.seriouseats.com/clean-cooking-oil-with-gelatin-technique