Black olives are olives which have been allowed to fully ripen on the tree before harvesting. They tend to have a different flavor from more immature green olives, and they can be cured in a variety of ways for different uses and flavor profiles. Like other products of the olive tree, black olives play an integral role in the cuisine of many Mediterranean nations, and they are popular in some other countries as well. Most grocery stores sell several forms of black olives.
All olives come from the olive tree, a Mediterranean tree which has been cultivated for thousands of years. The fruits can be pressed to produce olive oil, or cured to make olives. The wood has traditionally been used for some regional crafts, while the trees themselves are symbols of peace and goodwill. If well cared for, an olive tree can live for hundreds of years.
Unlike many fruits, an olive cannot be eaten right of the tree. Olives are naturally intensely bitter. Therefore, they must be cured in things like salt, water, oil, or lye. The fruits are also dry cured in some parts of the Mediterranean. The cure makes the olive palatable, adds a unique flavor and texture to the fruit, and often allows it to be stored for prolonged periods of time. Olives fall into two basic categories: green olives, which are picked before they are ripe, and black olives, which are ripened fully before curing.
Many consumers are familiar with California or Mission olives, which are traditionally cured in lye. These giant olives have a fairly neutral flavor and a meaty texture, and they are commonly used as a pizza topping and in some Latin American cuisine. Mission olives can also be made from green olives, which turn naturally black during the lye curing process.
Other common varieties of black olives include Kalamata olives, traditionally brined olives from Greece. The Italian equivalent is the Gaeta. Kalamatas have a salty, slightly acidic flavor, and come in pitted and unpitted forms. Small wrinkly salt cured black olives from Morocco are another favorite variety. Nicoise and nyon black olives from France are often cured with herbs, and they have a delicate, complex flavor. In Europe, some varieties of black olives are protected by an Appellation of Controlled Origin, in order to preserve regional history and culinary heritage.