Ingredient Information

Function

Extra virgin olive oil comes from pressing olives after they are crushed. This is unrefined oil that is extracted mechanically without the use of chemicals. As such, it has volatile properties and a distinct flavor. Extra virgin olive oil is not commonly used in cooking with high heat as most of the volatile compounds that are in it flash off (turn to vapor and burn) and are not available. This form of oil is commonly used in salad dressings, marinades, and dips.

The difference between virgin and extra virgin olive oil is the free fatty acid content of oleic acid. Extra virgin olive oil should not have more than 0.8% free fatty acid content. However, in 2011, the United States adopted new standards of identity for olive oil that set the free fatty acid content at 0.8%. It also must be extracted mechanically. These standards are currently voluntary, but may become required in the future.

Extra virgin olive oil is considered the highest quality olive oil and is quite expensive. Different varieties of olives are used to make it, and often, more than one variety is used in the same brand. A such, the type of olive used will determine the final flavor. Along these lines, there are olive oil connoisseurs who “grade” the oil based on flavor. They will describe it as fruity, pungent, or bitter based on the most abundant flavor tasted.

Extra virgin olive oil is believed to smoke between 365°F (185°C) and 400°F (204°C), which makes it suitable for sautéing but not for intense frying. As with most oils, it has a density of approximately 0.91 to 0.95, slightly less than water. It is a yellow to golden colored, slightly viscous liquid and is not miscible with water (capable of being mixed).

Other Use and Industries

Skin care is a huge market for extra virgin olive oil as it is considered a premium moisturizer containing many antioxidants. It has also shown up in numerous hair-care products, from all-natural lines to mainstream shampoos and conditioners. It is also being used in nutraceuticals (food products that reportedly provide health and medical benefits) for the beauty from within market. Despite the popularity of extra virgin olive oil as a beauty ingredient, it is still mainly used as a food product due to high cost and availability issues.

Health Effects

Extra virgin olive oil has been touted as the most healthful oil. Its fatty acid composition consists of approximately 15% saturated fat, 9% linoleic acid, and 75% oleic acid. Oleic acid is a monounsaturated fat that has been associated with a decrease in LDL cholesterol, which helps reduce the risk of heart disease. Meanwhile, antioxidants and polyphenols found in extra virgin olive oil have also been associated with increased cardiovascular health.

Since it is highly unrefined oil, extra virgin olive oil contains an abundant number of phytonutrients (chemical compounds found in plants as antioxidants and considered beneficial to human health). These phytonutrients (specifically, polyphenols or plant alcohols) help control excess inflammation in the human body. Polyphenols have also been shown to reduce the amount of C-reactive protein in heart patients, which helps control inflammation as well. Research studies have shown that it only takes 1 to 2 tablespoons a day to benefit from the anti-inflammatory properties of olive oil.

Other areas of health interest for extra virgin olive oil are digestive health, cancer prevention, and cognitive function. Many of these benefits also arise from the abundance of polyphenols along with the oil's oleic acid composition. For digestive health, an intake of olive oil daily has been shown to slow the growth of bacteria and help reduce inflammation. In regards to cancer, olive oil has been shown to protect DNA from excess oxidative stress. Extra virgin olive oil is related to cognitive health mostly because of the high oleic acid content (there is more oleic acid in the human brain than DHA) and there are many current studies to determine the effect of extra virgin olive oil on cognitive function. Although olive oil is a healthy fat, it should be taken in moderation due to its caloric value.

Origins

Olives are mainly grown in Italy, Spain, and Greece. They have been harvested for food and oil for thousands of years, with some references dating as far back as 3500 BC. In modern society, most olives are grown and harvested for their oil. When considering the amount of time is takes from seed to oil, olive oil production is a lengthy process. For example, it can take up to 15 years for trees to fully mature.

Once the fruit has ripened, the olive can be prepared for oil production. The olives are first cleaned and washed with water to remove debris, stems, and leaves. Then they are crushed into an olive paste. The purpose of crushing is to speed up the oil-removing processing. After crushing, they are mixed to allow the oil to combine in larger oil globules, which also makes extracting the oil easier. When the paste has been mixed, the olives are spun in a centrifuge that will separate the oil from the water and solids. This is done now in place of pressing, with the exception of old olive oil mills. For extra virgin olive oil, this step would be short and the free fatty acid content would be measured to ensure it meets the requirements for extra virgin quality. After separation, the oil is allowed to decant (to pour gently from one container to another without disturbing any sediment) to help separate the oil and water phases further.