In choosing your Olive Oil, there are some things to consider:
Dark Bottles! it is very important to choose olive oils in dark bottles, as olive oil is very sensitive to light and oxygen, and chances are that the oils in colorless bottles have already been oxidized and gone rancid before they even go on the shelves at the store!
Extra Virgin! Extra virgin olive oil is made using a process called “First Cold Pressed.” The word “first” refers to the olives being pressed on the first round of extraction. The “cold” refers to the temperature range of the fruit at the time it was crushed. If the temperature range is too high during the crushing process, the quality of the oil will suffer. The “pressed” refers to the method of extraction. This method indicates that no heat or chemical additives were used to extract the oil from the olives, which can alter and destroy the flavors and aromas of the olive oil. Without adding heat to the processing, the olive oil also retains its full nutritional value.
Organic! Its better to choose organic olive oils, because the chemicals can easily penetrate the olive and may not be completely removed with washing or peeling. Another reason to choose organic is the damage its production and farming can cause the environment as washing non-organic olives, feeds pesticides used to treat it into sewers and, subsequently, larger areas of water.