As its name suggests, olive oil comes from olives. There are different types of olive oil ranging from extra virgin to unrefined.
Olive oil goes through a complicated process. First, olives are picked from the olive branches. The olives are washed and crushed, usually by large steel blades. Once a paste has formed, it is continuously stirred to release the oil from the olives. Once the oil begins to release, it is spun out and put into a separate container.
Extra virgin olive oil has to be of a certain high quality to get the title "extra virgin." It is an unrefined oil that has higher amounts of nutrients and offers greater health benefits than other olive oils. Extra virgin olive oil may help prevent certain cancers, heart disease and diabetes.
Refined olive oils make up about 30 percent of olive oil production. It is considered finished at the end of the extraction process and may contain olives that are not at their peak. Labels containing the words "refined olive oil" or "olive oil" are refined oils.
Unrefined olive oil uses olives that are in better condition than those used to make refined oil. Because it doesn't go through any kind of chemical processing to hide bad or "off" flavors, he olives need to be of good quality.