If you really want to get the "crud" out of it, you need to do the following. Buy a commercial deep fryer with a built in filtering kit, then use the magnesol filter pads. These can be ordered through a few different companies.. I think GFS (Gordon Food Service) has them too. You heat the oil to 200f and then filter it for no less than 15 minutes. This will remove any impurities and any crud.