Olive Oil: Extra Virgin

The very least you must ask of an olive oil is that it be “extra virgin,” a double-barreled term. It is virgin when the olives’ oil is extracted solely by cold mechanical pressure, unsullied by solvents or other chemicals. Extra refers to the percentage of free oleic acid it contains. Free means the acid has been knocked loose from its bond with other compounds in the oil by rough handling of the olives or the use of fruit that is damaged, well past its prime, or even partly spoiled. For an oil to qualify as extra, the percentage of free oleic acid must be less than 1 percent. The healthier the olives, the lower the free acid and, when the oil itself is of high quality—a most important “when”—the aromas and flavors that play such a significant role in those dishes where olive oil is present will be more clearly expressed.