Both of these oils are good for frying. If you use virgin olive oil for frying potatoes and you keep the temperature below the smoke point of the oil you will come out with a very tasteful product. Olive pomace oil is also recommended for frying due to the fact that it is cheaper than virgin olive oil. Consumers have to realize that olive oil alters less during frying and cooking, than any other vegetable oil. The bulk of available evidence suggests that when olive oil is properly heated, degenerative effects appear to be less than those of other vegetable oils.
Olive oil is a complex mixture of oils and waxes.
The heavier oils and waxes will form needle-like crystals as the temperature is lowered, then the other oils will start to settle out. Winterization is the commercial process whereby these waxes are removed to keep the oil clearer when stored on a cold shelf. It is used mostly for aesthetics. There is no exact freezing temperature. The more the oil has gone rancid or oxidized, the more the peroxides.