Know Your Table Olive Types and VarietiesBy admin Posted in: Olive Information on September 8th, 2011
The olive fruit is considered a drupe. It has a bitter component (oleuropein), a low sugar content (2.6-6%) compared with other drupes, such as a cherry (12% or more), and a high oil content (12-30%) depending on the time of year and variety.
These characteristics make it a fruit that cannot be consumed directly from the tree. Olives must undergo a series of processes that differ considerably from region to region and variety. Some olives are an exception to this rule, because as they ripen, they sweeten right on the tree. In most cases this is due to fermentation. One case in point is the Thrubolea variety in Greece.
Oleuropein, which is distinctive to the olive, has to be removed as it has a strong bitter taste: it is not, however, detrimental to health. Depending on local methods and customs, the fruit is generally treated in such a way that removes the oleuropin.
Semi-ripe olives are obtained from olives picked as their color is starting to change. They are harvested before full maturity, when the flesh is quite firm but oil formation has not concluded. The process of darkening the fruit by oxidation is typical of California. Olives suitable for processing as green olives are selected as they enter the factory, then placed in brine and protected from air.
Green olives are obtained from olives harvested during the ripening cycle when they have reached normal size, but prior to color change. They are usually hand picked when there is a slight change in hue from leaf-green to a slightly yellowish green and when the flesh begins to change consistency but before it turns soft. Color change should not have begun. Green olives are taken to the plant for processing on the same day if possible.
Green olives are processed in two principal ways: with fermentation (Spanish type) and without fermentation (Picholine or American type). The most commonly used varieties are Manzanillo, Gordal and Moroccan Picholine.
These are olives that are harvested when the fruit is close to full ripeness, when it has attained the color and oil content corresponding to each particular variety. There are many types of preparations depending on local tastes.
Black Olives in Brine
These are typical of the eastern Mediterranean countries. The most commonly used varieties for this process are Conservolea, Gemlik and Kalamata.
Black Olives in Dry Salt
Also of Greek origin, these are prepared using overripe olives of the Megaritiki variety.