Extra Olive Oil.

The most important qualifier for extra virgin classification is the "absence of sensory defects and the presence of some olive fruitiness."

-- International Olive Council

Many factors will determine the flavor of olive oil including age, type of varietal, where it was grown, climate, rainfall, etc. Also, when the olives are picked will have a big influence. Olives picked when more green tend to have a more robust, peppery, pungent flavor. Olives picked when more ripe, tend to have a softer, more buttery flavor. Bitterness and pungency decline as olives ripen, and oil made from ripe olives can have little or none of those qualities. Ripe oils are also less stable, since bitterness and pungency indicate the presence of antioxidants that preserve freshness. The shelf life of a properly stored high polyphenol olive oil can be up to two years. A ripe, low-polyphenol oil can become rancid in half that time. Degree of ripeness is a question of style and a regional or personal preference. It is important to remember that there is a difference between olive oil tasted straight out of a glass and olive oil used on food. The bitterness and pungency of an oil are much less prominent when the oil is paired with the right food.