Olive Oil Quality

Virgin and Extra-Virgin Olive Oil

The term “virgin olive oil” is used to describe olive oil that is manufactured from olives purely by mechanical processes or other methods that do not alter the olives and the subsequent oil in any way, either through heat or chemical processes. Thus the only processes that should have been carried out on the olive oil are washing, centrifugation and filtration.

“Extra-virgin olive oils” are the highest quality olive oils, and have been cold-pressed. This is a process during which olives are turned into olive oil solely through the use of pressure and no chemicals. This produces oil with a naturally low level of acidity.

The taste, aroma and color of olive oils are determined by the conditions in which the olive trees are grown and the time at which the olives are harvested. The variety of the olives also plays a large part in determining those characteristics.

Differences Between Extra-Virgin, Fine Virgin, and Ordinary Virgin Olive Oil

Olive oils are classified into either one of the following two categories – extra-virgin olive oil and virgin olive oil – according to two different properties. The first is acidity. Extra-virgin olive oils must not have an acidity of one percent or more, while virgin olive oils may have an acidity ranging from between one to two percent. The other is organoleptic property ratings. Extra-virgin olive oils must score at least 6.5 when rated by an Italian tasting panel on a scale of 1 to 10. Organoleptic values for virgin olive oils must be 5.5 or higher.

Besides those already listed, other classification standards exist as well. The International Olive Oil Council has given virgin olive oils the following designations:

In order to be classified as Extra-Virgin Olive Oil, the virgin olive oil must have an organoleptic rating of at least 6.5 out of 10, and relatively low acidity. Extra-virgin is the highest quality of olive oil and possesses a rich, fruity flavor. Its color ranges from crystalline champagne to greenish-golden to bright green.

Extra-Virgin Olive Oil has a multitude of uses for cooking and the Italians use it as an ingredient in almost everything, from antipasti to desserts. In order to fully appreciate its taste, however, it is best consumed raw. Extra-virgin olive oil is invariably expensive because the process of its manufacture is extremely tedious and time-consuming. Any cheap olive oil that is labeled as being “extra-virgin” is most probably not a real extra-virgin olive oil.

Directly below the designation of Extra-Virgin Olive Oil is that of Fine Virgin Olive Oil. Fine Virgin Olive Oil must also be cold-pressed, have an organoleptic rating of at least 5.5, and have an acidity of 1.5 percent and below. The quality of olive oil is determined by the length of timebetween harvesting and pressing, as the fruits undergo fermentation during the time that they are stored. The fermentation process increases the acidity of the resulting olive oil and causes the quality of both flavor and fragrance to deteriorate.

Semi-fine, or Ordinary Virgin Olive Oil, possesses an organoleptic rating of at least 3.5 and an acidity percentage of 3.3 or lower. The quality of the olive fruit’s taste, fragrance and vitamins may be retained even in Ordinary Virgin Olive Oil through proper processing. Ordinary Virgin Olive Oil is recommended for use in cooking by the International Olive Oil Institute because the taste of extra-virgin olive oil tends to deteriorate at high temperatures.

Testing to Determine Whether an Olive Oil is Extra-Virgin

In order to test the accuracy of the Extra-Virgin classification, place a small amount of olive oil in a container and refrigerate it for several days. Extra-Virgin olive oil should solidify into a crystalline form, whereas ordinary olive oil tends to form a block-like lump.

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