How often should you change deep frying oil?

After eight to ten usage, the majority of oils need to be replaced. After each usage, the oil in the deep fryer must be drained, strained, and stored in the appropriate manner until the next time it is required. A useful piece of advice is to store the filtered oil in a cold, dark area until the next time it is needed. This is because any food residue that is left in the oil will give it an unpleasant flavor.