Extra virgin olive oil refers to a specific grade of consumer olive oil that is made from the initial pressing of the olives. It is considered by most people to be the highest quality variety, with the finest taste and texture.
Olive oil is a hugely popular oil throughout the world, both for cooking and for eating as a condiment with foods. Mediterranean countries produce the vast majority of the world’s supply, and oil from these countries is generally considered to be the finest. Although the oil is also used for industrial applications, the term "extra virgin olive oil" refers only to consumer-grade oil, and should not be confused with the "virgin oil" designation given to some industrial products.
An international body, the International Olive Oil Council (IOOC), grades consumer oils and designates whether they are extra virgin, virgin, or a lesser grade. The IOOC is made up of 23 different countries, and the United States is notably not a member of this body. For this reason, although many olive oils made in the United States are graded as extra virgin olive oil, the US Department of Agriculture (USDA) does not technically recognize the grade.
There are essentially four grades of consumer olive oil. At the top is extra virgin, which must be pure. Next is virgin, which cannot include refined oil. Next is simply olive oil, which may be a blend containing refined oil. Last is what is called pomace oil, which is mostly refined oil made from the left-over pomace — it is the lowest grade of oil, usually only used for restaurant cooking, and is not actually referred to as olive oil.
Extra virgin olive oil is differentiated from virgin and the lower grades in a number of ways. To begin with, it is the oil that comes out in the first pressing of the olives. Olives contain a large amount of oil, and subsequent pressings will squeeze out more, but extra virgin is always the first — and best — press from a batch of olives. This oil is also entirely pure, 100% first press oil, unlike standard olive oil, which may include some refined oils, to help bulk it out. As a result, extra virgin olive oil has a very low acidity — less than 1% — and the flavor tends to be very pronounced and smooth, with a very unique, interesting taste. Lower-grade oils may have bland flavors.