Donnalisa - Olive oil properties

Olive oil is composed for the most part of so-called saponifiable material (98.5% - 99.5%), made up of triglycerides (glycerine esters with fatty acids) and free fatty acids. The majority are fatty acids containing eighteen carbon atoms which can bind with either single bonds (saturated fatty acids), single bonds with one double bond (mono-unsaturated fatty acids), or with numerous double bonds (poly-unsaturated fatty acids).

With greater numbers of double bonds, the molecule becomes unstable and tends either to form peroxides (when it combines with oxygen), or give rise to free radicals (when the double bonds remain open). Bearing this in mind, it is easy to understand the rôle that fats play in the body.

The remaining olive oil content, the unsaponifiable material, amounts to only a tiny fraction, but is biologically extremely important. The presence of chlorophyll and carotene gives olive oil its green or reddish colour. The aromatic, volatile components have an influence on its flavour and perfume. The polyphenols, the main cause of olive oil’s bitter flavour, have an anti-oxidant action, and this is the determining factor in the oil’s stability, and consequently its keeping and aging process. The tocopherols (vitamin E) that are present have the same anti-oxidant action. Olive oil does not contain cholesterol.

Olive oil is a condiment that has thick consistency and a distinctive perfume and flavour. These characteristics have, on the one hand, been highly prized, being especially pleasing on the palate, but on the other hand, they have given ground to the mistaken idea that olive oil is more fattening than other oils. In actual fact, all oils are composed of 99% lipids, and so they all provide 9 kcal per gram. Values lower than this can only be found in fats such as butter and margarine, but only because they contain a certain amount of water.
The application of olive oil is recommended for conditioning the hair to maintain its structure and shininess. It is used to heal the skin after a burn and to protect it from sunburn. It is also widely used for massaging the muscles and joints.
Olive oil is highly digestible, in that it stimulates the secretion of the gastric juices. Furthermore, it protects the lining of the stomach, and provides effective anti-inflammatory protection against gastritis and stomach ulcers.
This oil has a positive effect on conditions of the hepatic system, helping to protect the liver.
By stimulating the secretion of bile, olive oil reduces the risk of gallstones and lowers cholesterol levels in the blood, thus keeping the arteries clear. The action that olive oil has on cholesterol can be defined as selective, because it takes effect only on cholesterol carried by the low density lipoproteins (LDLs), whilst the cholesterol carried by the high density lipoproteins (HDLs) remains stable. This fact becomes particularly important when one considers that LDL cholesterol is notoriously plaque forming, whilst HDL cholesterol has the opposite effect.
Since it helps protect the lining of the intestines and regulate peristalsis, olive oil can be used for constipation from either lazy intestines or spastic colon caused by irritable bowel syndrome.
Olive oil enables the body to absorb more vitamins, and in particular, vitamin E.
Olive oil is particularly suited for child feeding. Its fatty acid composition is very similar to the composition in the fatty acid content of breast milk. This applies to both the essential fatty acids, linoleic acid and α-linoleic acid, and to oleic acid, which benefits the growth of the long bones and the myelination of nerve fibres newborn babies. This explains why, before the advent of homogenised baby food, most of us were weaned, by one parent or the other, and quite unbeknown to either, on a diet of pan cotto (bread and vegetables in broth) and extra virgin olive oil.
Extra virgin olive is highly recommended for the elderly because it is both easily digested, enabling a higher absorption of fat-soluble vitamins, and gently laxative, providing relief for constipation from lazy intestines, so common at this age. The poly-unsaturated fatty acids have a significant effect against cellular aging and cerebral degeneration, whilst oleic acid replaces vital minerals, and is remarkably beneficial for osteoporosis, common amongst the elderly and especially in menopausal women.
Olive oil is more resistant to the kind of high temperatures reached, for example, with frying, than any other oil. Its critical temperature, the point at which molecular break-down begins, is around 210°C-220°C.
The presence of anti-oxidants and its medium content of unsaturated fatty acids make extra virgin olive oil by far the best oil to use in every situation, whether cooked or uncooked. Indeed, animal fat low in unsaturated fats, do not contain anti-oxidants and quickly go rancid (butter exposed to the air goes off very quickly), damaging the circulatory system by accumulating on the wall of arteries. Vegetable seed oils, on the other hand, have a high level of unsaturated fats, but once exposed to thermal treatment, after a short time, their composition is modified completely. Firstly, peroxides and polymers form causing damage to the liver, kidneys, stomach and cardiovascular system. Secondly, free radicals are created capable of changing the chemical make-up of the cellular membrane and putting certain enzymes out of action. Thirdly, as a consequence, free radicals can provoke cellular mutation linked to the cause of cancer. Furthermore, the oil from various kinds of seeds is extracted with the aid of solvents. Later on, the oil is treated with deodorants and colorants, as happens with olive pomace oil, thus compromising their nutritional value. In fact, the wealth of polyphosphates (a result of the high unsaturated fat content) found in good quality seed oils ought to make their use when uncooked very beneficial for those who have high blood cholesterol levels and cardiovascular problems.