All About Olives

The fruit of the olive tree has a long, rich history as a symbol of peace, new life, hope and honor.  These days, it is best known as a symbol of good health.

The cultivated olives we know today had wild ancestors that go back hundreds, if not thousands, of years B.C.  You may think there are only two types of olives—green and black-and, to some degree, this is true. Green olives are unripened fruit, while black olives are fully ripened. But no olive-green or black—is edible when it is first picked from the tree.

Although hundreds of green and black varieties of olives are produced around the world, the differences among most of them are relatively subtle. Some are more bitter than others, and texture may vary, but what distinguishes most olives is the difference in how each is cured.

Olives grow in Mediterranean Europe, Africa and Asia as well as in the United States. Italy and Spain are the largest olive producers in the world. Since ripe olives require a long, hot growing season, most American-grown varieties come from California's Central Valley region, while a small number grow in the deserts of Arizona.

The most common variety of green olives seen (and grown) in the U.S. is the Manzanilla, or Spanish olive. Those are the pimiento-stuffed olives you see in every supermarket, where you will also see the ripe California Mission olives. Commonly available European olives include Greek Kalamata (or calamata), which are also sold in most American supermarkets, and French ripe Nicoise and green Picholine and cracked Provencal olives, more easily found in ethnic and specialty, or gourmet, food markets.

Raw olives are pickled in brine, cured in oil, or packed in dry salt for a period of time before they are re-packed in fresh brine for commercial sale. The longer the olive is allowed to ferment in its brine, the less bitter and more complex its flavor becomes. Typically, American Mission olives, and some green olives, are cured in a lye bath to remove their natural bitterness before brining. It is possible to find natural and organic varieties that have not been soaked in lye, but you have to seek them out.

Olives are one of the leading organic crops grown around the world, along with fruits, coffee, nuts and cocoa beans. As with any other organic crop, organic olives are grown without the use of chemical pesticides and other synthetic agricultural products. Organic or not, however, most of the olives grown around the world are used to make olive oil; only about 10 percent are cured and sold as whole fruit. For the most part, the olive varieties pressed for oil are different than those sold whole.

An olive is actually 20 to 30 percent oil. If you wonder why olive oil is so expensive, consider that it takes a ton of olives to produce between 10 and 30 gallons of oil. The quality and taste of the oil, as well as the price, depends on both the varieties and maturity of the olives used. Most olive oil is a blend of oils and the best is pressed from a mixture of green olives and olives that are called "red-ripe" because they are riper than green olives but not as ripe as black olives.

The first pressing of olives yields the highest quality oil, which is virgin olive oil. Even within the virgin oils, however, there are graded levels of quality, depending on the acidity of the oil. Extra virgin is the highest grade, with an acidity of less than 1%. Plain virgin olive oil has an acidity of up to 4 percent so it has a little more "bite" than extra-virgin and those graded "fine (up to 3 percent)" or "superfine (up to 1.5 percent)." Second and third pressings of the olive mash leftover from the virgin pressing yield standard quality oils are simply labeled "olive oil" or "pure olive oil." 



Cook's Thesaurus: Olives

Lindsay Olives: Curing Methods

Union County College Biology Department: The Olive

University of Arizona College of Agriculture and Life Sciences: Olives

Washington State University Extension: "WSI Extension Specialist's Article Captures Global Growth in Organic Horticulture