olive oil, pale yellow to greenish oil obtained from the pulp of olives by separating the liquids from solids. Olive oil was used in the ancient world for lighting, in the preparation of food, and as an anointing oil for both ritual and cosmetic purposes. It is produced mainly in Algeria, Greece, Italy, Morocco, Portugal, Spain, Tunisia, and Turkey. The characteristics of the oil vary with the climate, cultivation, and variety of olive. Olive oil is one of the most digestible of the edible oils. To make the finest, or extra-virgin olive oil, the fruit is gathered when fully ripened, ground to a paste under granite or steel millstones, layered over straw mats, and pressed in a hydraulic press. Today, most olive oil is produced by just one pressing. The resulting oil is separated from the juice by settling or by centrifuge and then filtered. Olive oil of good quality is ready to use, without further refinement. Although olive oil occupies a relatively minor place in world food consumption, it has, in recent years, become a stronger export item, and a succession of international agreements have been signed since 1959 to protect its market. Olive oil is now the third best-selling cooking oil in the United States. Both gourmets and health professionals have praised its qualities, thereby contributing to its growing popularity. Olive oil is a monounsaturated fat and, unlike butter, lard, and other fats, contains a large proportion of easily digested fats and no cholesterol. Olive oil is also a good source of vitamin E, which is thought to help protect humans against cancer and heart disease. The principal fat in the diet of countries where it has long been cultivated, olive oil is often used in place of cream and butter and as a cooking fat and salad oil. Although olive oil is chiefly used as a food or in food preservation, it is also used in soaps, certain pharmaceuticals, and cosmetics.
See A. Dolamore, The Essential Olive Oil Companion (1989).