Feeding and Diet

Chef's favorite olive oil is the chief source of edible oils all over the Mediterranean region since ancient times. The oil pressed from the olive fruits oftentimes revered in the many religious texts as symbol of peace and good health.

Olives belong to the family of Oleaceae of the genus Olea and their scientific name is Olea europaea.

Olive tree is a slow growing evergreen tree with gnarled trunk and slender grey, fissured branches. It may reach up to 50 feet in height in their natural habitat and live for more than 500 years. It grows well in frost free, dry, well-drained warm soils. Its fruits are generally picked when they matures from green to yellow-green and starts to soften (veraison stage). Olives harvested at this stage contain high polyphenols, and are believe to be at their peak for oil production.

Physical characteristics of olive oil

The oil cold pressed from freshly picked olives is light green to deep yellow depending up on fruit maturity. Green olives yield greenish, bitter and pungent oil while black fruits pressed to less pungent, yellow oil. Fresh oil has very low free fatty acids (FFA) and natively cold pressed oil has less than 0.5% FFA. Extra virgin oils have less than 0.8% FFA.

Extra virgin is the highest grade of olive oil. As with all virgin oils, it is made mechanically, without the use of chemicals or excessive heat. Its specific gravity @ 15.5 ?C is 9150–0.9180, Iodine value-75 – 94, and saponification value-184 – 195.

Olive oil nutrition facts

• Olive oil is the best edible oil in terms of palatability, stability, lipid profile, and safety profiles.

• It is high in energy; 100 g oil provides 884 calories. However, its high ratio of more mono-unsaturated fatty acids to saturated fatty acids makes it healthy oil for consumption.

• Extra virgin oil has high smoke point, 450 ?F (210 ?C). The property which can be employed in setting oil temperature while deep-frying food items.

• Olive oil has excellent lipid profile. It has saturated, mono-unsaturated and polyunsaturated (SFA: MUFA: PUFA= 14: 77: 9) fats in healthy proportions.

• Natively cold pressed oil is one of the stable cooking oils that have very long shelf life.

Health benefits of olive oil

• Olive oil has distinct flavor and unlike many other oils, which are derived from nuts and seeds, olive oil is obtained from fruits and hence contains large amounts of plant-derived anti-oxidants, phyto-sterols and vitamins.

• It is very low in saturated fats, contains linoleic (omega-6) and linolenic acid (omega-3) essential fatty acids at 8:1 ratio making it as one of the healthiest cooking oils.

• Olive oil is high in calories. The high calorie content is because of its fats. However, it is especially rich in mono-unsaturated fatty acids (MUFA) like oleic acid (18:1) and palmitoleic acids (16:1) that help to lower LDL or "bad cholesterol" and increase HDL or "good cholesterol" in the blood. Research studies suggest that Mediterranean diet, which is rich in monounsaturated fatty acids helps to prevent coronary artery disease and strokes by favoring healthy blood lipid profile.

• Olive oil contains oleuropein and oleocanthal a tyrosol phenolic compounds that gives extra-virgin olive oil its bitter, pungent taste. Oleocanthal, oleurpein and its derivative hydroxytyrosol are nature’s most powerful anti-oxidants. Together, with vitamin E and carotenoids, they play vital role against against cancers, inflammation, coronary artery disease, degenerative nerve diseases, diabetes…etc.

• Studies suggest that oleocanthal has ibuprofen (NSAID) like ant-inflammatory activities. 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 ?-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 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 cell membrane of mucus membranes and skin by protecting it from harmful oxygen free radicals.

• In addition, extra virgin oil is also very good source of vitamin K; 100 g provides about 50% of DRI. Vitamin K has potential role in the increase of bone mass by promoting osteotrophic activity in the bone. It also has established role in Alzheimer's disease patients by limiting neuronal damage in the brain.

Selection and storage

Several different grades of olive oil displayed for sale in the markets. Buy recently pressed oil from mature greenish-yellow olive fruits using cold-pressing methods, as it is purest and rich in flavor and high levels of anti-oxidants. This natively cold pressed oil is devoid of chemicals, less acidic, has highest smoke point and long shelf life.

Extra virgin oil is also cold pressed however with machines, without the use of chemicals or excessive heat. It has acid content of less than 0.8%. Following this are virgin at 1.5% and ordinary virgin oil at less than 3%.

Pomace olive oil is refined oil obtained from the final pressings and under heat and pressure. It is inferior in quality and is generally not used for cooking.

Since adulteration is quite common check for authenticity of the product. Look carefully for "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 in a cool, dark place away from heat or light.

Culinary use

Olive oil is the chief edible oil of Mediterranean, Asia Minor, as well as North African regions. However, its use is fast spreading across the continents among health conscious people.

Olive is one of the most sought after culinary oil used either for cold foods (salad dressing, gourmet oil) or for frying and saut?ing vegetables, meat and poultry.

Here are some serving tips

• Andalusian salad- specialty from southern Andalusia province of Southern Spain uses tomatoes, onion, bell pepper, thyme herb cucumber with added extra virgin oil.

• Eggplant fry in olive oil with tomatoes, onions, capers with black pepper and added salt to taste is a favorite Italian recipe.

• Olive tapenade- This is a kind of traditional dip from 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.

Safety profile

Olive oil can be safely used on daily basis. Unlike some nuts and seed oils, it has no allergic agents.