Chef's favorite, olive oil is one of the principal sources of cooking edible oils employed all over the Mediterranean region for centuries. The oil, pressed from olive fruits, oftentimes is revered in many religious texts as a symbol of peace, prosperity, and good health.
Olives belong to the family of Oleaceae, in the genus: Olea. Scientific name: Olea europaea.
|Native pressed pure extra virgin oil. Note the olive-green color of the oil due to chlorophyll, carotenoids, and oleuropein pigments.
Photo: By Monica.
Olive is a slow-growing evergreen tree with a gnarled trunk and slender gray, fissured branches. It may reach up to 50 feet in height in its natural habitat and may live for more than 500 years. It grows well under frost-free dry environments assisted by well-trained, warm soil conditions.
|Olive tree. Courtesy: A.Poulos|
Olive fruits are generally picked when they become plump, mature, turn light green to yellow-green, and begin to soft (veraison stage). Olives harvested at this juncture contain high quantities of polyphenol and are believed to be at their best for oil extraction.
Cold-pressed olive oil from the freshly harvested berries features light green to deep yellow depending on their maturity and veraison stage. Green olives yield greenish, bitter, and pungent oil while black fruits can be pressed to relatively less pungent, yellow oil. Fresh oil has very low free fatty acids (FFA), and natively cold-pressed oil should have less than 0.5% FFA. In general, virgin oils should have less than 0.8% FFA.
Extra-virgin is the highest grade of olive oil. As with all virgin oils, it is pressed mechanically without employing chemicals or excess heat. Its specific gravity @ 15.5 °C is 0.9150–0.9180, Iodine value-75–94, and saponification value-184–195.
Olive oil is the best edible oil in terms of palatability, stability, lipid profile, and safety profile.
It is rich in energy; 100 g oil provides 884 calories. However, its high ratio of monounsaturated fatty acids to saturated fatty acids qualifies it as one of the healthiest oils for consumption.
Extra virgin oil has a high smoke point at 450 °F (210 ºC). This property of olive is crucial when employing it in high-temperature cooking; as in deep-frying of certain food items.
Olive oil has an excellent lipid profile. Saturated, monounsaturated, and polyunsaturated (SFA: MUFA: PUFA= 14: 77: 9) fats in it distributed in good proportions.
Natively cold-pressed oil is one of the stable cooking oils featuring a very long shelf life.
Olive oil has a distinct flavor and taste. Unlike many other oils, which are extracted from nuts and seeds, the oil is obtained from olive berries and hence, carries large amounts of plant-derived antioxidants, phytosterols, and vitamins.
Olive oil is recognized as one of the healthiest edible oils since it contains less saturated fats. Additionally, it composes linoleic (omega-6) and linolenic (omega-3) essential fatty acids at a recommended 8:1 ratio.
The oil is high in calories. Its high-calorie content chiefly comes from its fats. However, it is especially rich in mono-unsaturated fatty acids (MUFA) like oleic acid (18:1) and palmitoleic acid (16:1) that help to decrease LDL or "bad cholesterol" and to increase HDL or "good cholesterol" in the blood.
Research studies suggest that the Mediterranean diet, which uses monounsaturated fatty acids-rich oils like olive oil, helps in the prevention of coronary artery disease and strokes by favoring a healthy blood lipid profile.
Olive oil, especially extra virgin, contains tyrosol phenolic compounds such as oleuropein and oleocanthal. These compounds are responsible for olive's bitter, and pungent taste. Oleocanthal, oleuropein, and its derivative hydroxytyrosol are nature’s most powerful antioxidants. Together with vitamin E and carotenoids, they play a vital role in fighting against cancer, inflammation, coronary artery disease, degenerative nerve diseases, diabetes, etc.
Studies suggest that oleocanthal has ibuprofen (NSAID) like anti-inflammatory activities. The Mediterranean diet that uses olive oil may be responsible in part for the low incidence of coronary artery disease.
Being a vegetable source, it has very high levels of plant sterols, especially ß-sitosterol. The FDA has approved the following claim for phytosterols: "Foods containing at least 0.4 gram per serving of plant sterols, eaten twice a day with meals for a daily total intake of at least 0.8 gram, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease". Phyto-sterols competitively inhibit cholesterol absorption in the gut and thereby can reduce total cholesterol levels by 10% to 15%.
Olive oil is rich in vitamin E. 100 g fresh extra-virgin oil contains 14.39 mcg (about 96% of RDA) of alpha-tocopherol. Vitamin E is a powerful lipid-soluble antioxidant required for maintaining the integrity of the cell membrane of mucosa and skin by protecting it from harmful oxygen-free radicals.
Additionally, extra-virgin oil is also an excellent source of vitamin-K. 100 g provides about 50% of DRI. Vitamin K has a potential role in the increase of bone mass by promoting osteotropic activity in the bone. It also has established a role in the treatment of Alzheimer's disease patients by limiting neuronal damage in the brain.
|Principle||Nutrient Value||Percent of RDA|
|Total Fat||100 g||500%|
|Dietary Fiber||0 g||0%|
|Pantothenic acid||0 mg||0%|
|Iron||0.56 mg||7 %|
In the markets, several different grades of olive oils can be displayed for sale. Buy fresh, cold-pressed oil that employs ripe greenish-yellow fruits since it is considered the purest, highest-graded oil, has superior flavor, and is rich in antioxidants. Native oil extracted using traditional methods is devoid of chemicals, less acidic, has the highest smoke point, and long shelf life.
Extra virgin oil can also be cold-pressed, however, using machines, without adding chemicals or excessive heat. It has an acidity content of less than 0.8%. Following this are; virgin oil at 1.5%, and conventional virgin oil at less than 3%.
Pomace olive oil is refined oil obtained from the final pressings under high heat and pressure. It is inferior in quality and generally not used for cooking.
Since adulteration is quite common, check for the authenticity of the product. Look carefully for terms like "best before," "virgin," "native cold-pressed,"...etc. Buy extra-virgin oil certified by the COOC (California Olive Oil Council) or IOC (International Olive Oil Council).
Always store olive oil in tightly sealed containers and place it in a cool, dark place away from heat or light.
Olive oil is the leading edible oil of the Mediterranean, Asia Minor, as well as North African regions. However, its use is fast spreading across the continents, particularly among health-conscious people.
Olive is one of the most sought-after culinary oils used either in raw foods (salad dressing, gourmet oil) or for deep-frying and sautéing vegetables, meat, and poultry.
Here are some serving tips
Olive tapenade-This is a kind of traditional dip originated in the South of France made with black olives, walnuts, onion, garlic, pepper with added lemon juice. It can be served as a spread or as a dip.
Olive oil can be safely used on a daily basis. Unlike some nuts and seed oils, it has no allergic components. (Medical disclaimer).
≻≻-Back to Dietary oils and fats from Olive oil.
≻≻-Back to Home page.