The most refined olive oil is called 'extra virgin.' To be called so, the olives need to be crushed within 24 hours. They also need to be 'cold pressed,' meaning the oil is extracted mechanically ...

For example, according to regulations from the USDA, U.S. extra-virgin olive oil has to meet specific purity and quality criteria. Cold-pressed, on the other hand, is not quite as closely controlled.

Along with a great Greek extra-virgin olive oil for cooking, I keep cold-pressed citrus and herb olive oil on hand as well to drizzle on just before serving. The citrus oils are even exceptional ...