For Extra Virgin Olive Oil (EVO) we mean an oil obtained from the first pressing of the drupes, or the fruits (olives), of the Olea europea Leccino plant (better known as olive tree). The processes of extracting extra virgin olive oil are MECHANICAL and the use of chemical means or processes is totally excluded;
NB. The pH of extra virgin olive oil is expressed in free fatty acids of oleic acid (C 18: 1); from the food legislative point of view, an EVO oil must not exceed 0.8% of free C 18: 1.
Nutritional properties and cuisine
Extra virgin olive oil is 99% lipid. The saponifiable portion of these fats is organized mainly in simple triglycerides (or triacylglycerols) (glycerol esters with three fatty acids) and / or mixed.
The quality of the fatty acids of the extra virgin olive oil determines their chemical-physical properties and, in practice, their relative relevance within the various culinary preparations. At the same time, the unsaponifiable portion of extra virgin olive oil provides many essential micro-molecules (fat-soluble vitamins - tocopherols and B-carotene), or at least very useful for the human organism (phytosterols and polyphenols); Well, some of these molecules contribute, together with the typical fatty acids, to determine the chemical-physical properties of the finished product (antioxidants).
The fatty acids mostly present in the triglycerides of extra virgin olive oil are: oleic acid (monounsaturated - predominant on the others), palmitic acid (saturated), linoleic acid (polyunsaturated - family of ω ‰ 6) and α-linolenic acid (polyunsaturated - family of ω ‰ 3). The prevalence of oleic acid gives the extra virgin olive oil unparalleled properties; this fatty acid, chemically monounsaturated determines:
- A point of sufficient smoke for FRYING; this parameter is physically determined by the saturation level of fatty acids (saturates have a higher smoke point than unsaturated ones and monounsaturated ones have a higher smoke point than polyunsaturated ones) and by the amount of free fatty acids (> ac. free fats <point of smoke). It is also true that lard, refined and / or seed and / or hydrogenated oils boast a higher resistance to high temperatures, but the quality of fatty acids and their impact on metabolism are nowhere near comparable to those of oil extra virgin olive oil. To learn more, read the article: ideal oils for frying.
- Oxidative stability useful for STORAGE; they are particularly stable to oxidation and therefore contribute to determining the indispensable conservative properties in immersion packaging; on the contrary, the other fats used in the kitchen (with the necessary differences) do not possess equally good oxidation resistance characteristics. To learn more, read the article: preservation in oil.
At the same time, unsaponifiable micro-molecules such as glucosides (polyphenols) and antioxidant vitamins (tocopherols / vit.E + Β-carotene or carotenoids in general) contribute to increasing the conservative properties of extra virgin olive oil. However, it is also necessary to remember that: in the event of heat treatments being used (cooking / frying or simply post-invasive heating for oil preservation), the quantity of antioxidant molecules and the integrity of polyunsaturated fatty acids could undergo a remarkable molecular decline.
Nutritional properties and dietary contextualisation of extra virgin olive oil
As already explained, extra virgin olive oil is a good substrate for frying and an excellent food for preservation in oil. The nutritional properties, compared to any condiment gass, are definitely better; starting from the assumption that it is a food widely appreciated thanks to typical taste and palatability, the extra virgin olive oil deserves to be used "raw" with free frequency but in doses proportionate to the real caloric needs of the subject. Finally, we recall that extra virgin olive oil provides vitamins, antioxidants, phytosterols and monounsaturated fatty acids, therefore, to replace the saturated lipid portion of animal origin (fats contained in cheeses, in meat and fat derivatives, in eggs, etc.) can determine a significant nutritional advantage.
Focusing on the content of monounsaturated fatty acids, it is not uncommon to hear that extra virgin olive oil is compared to other vegetable oils and discredited due to the lower content of essential fatty acids ω3 (more abundant in linseed, soy, walnut oil etc.); in reality, this comparison has no reason to be supported. First of all, I would challenge anyone to fry or store food in oils rich in polyunsaturated fatty acids; the result would be a real disaster as the presence of double bonds gives the fatty acids considerable instability to heat and oxidation. Secondly, it is necessary to remember that:
- Even monounsaturated fatty acids, like many polyunsaturated fats, are characterized by a POSITIVE metabolic impact; they are distinguished by their beneficial effect on the blood lipid profile and therefore contribute to the prevention of cardiovascular diseases.
- The polyunsaturated fatty acids of the ω3 family present in vegetable oils are NOT totally bioavailable; the ω ‰ 3 contained in soy oil, flax oil, walnut oil etc. they mainly contain α-linolenic acid (abbreviations ALA, AaL, LNA or 18: 3-ω3) which, unlike eicosapentaenoic acid (EPA, 20: 5 ω ‰ 3) and of docosahexanoic acid (DHA, 22: 6 ω ‰ 3), it needs a molecular conversion to carry out its metabolic functions.
Obviously, the same goes for the extra virgin olive oil ... however, if the presence of ω3 fatty acids is the only discriminating factor in the choice between extra virgin olive oil and other seasoning oils, in my opinion there are no differences. sufficient to prefer a less pleasant oil than EVO, which also has a great culinary "ductility".
We conclude by recalling that the extra virgin olive oil, although characterized by: the excellent contribution in functional non-energetic micro-molecules, the excellent lipid profile, the conservative utility, the possibility of use in frying and the excellent taste characteristics, in any case, it represents a condiment fat that provides 899 kcal per 100g of product. In the context of a balanced diet (and especially in the case of any metabolic pathology ) the lipid content of EVO (and that of blue fish) should replace as much as possible the saturated fat portion deriving from meat, eggs and milk derivatives ... but this does not mean that it can be consumed in freedom! Ten grams of extra virgin olive oil (enough to season, for example, with a plate of salad or boiled zucchini) alone make up three times the calories supplied by the dish itself; it follows that to exaggerate in the seasoning of the various dishes with extra virgin olive oil has a more than decisive influence on the overall energy intake and on the breakdown of the macronutrients (which should include a lipid intake of between 25 and 30% of the total kcal).
Other applications of extra virgin olive oil
Extra virgin olive oil also has properties and applications that are very different from those of cooking; it, as we have already mentioned, has both a saponifiable portion and a NON saponifiable portion of liquid and yellow color (also called Olea Europeae Oil Unsaponifiables ). The latter consists of 80% of SQUALENE and 20% of hydrocarbons, triterpene and aliphatic alcohols, sterols, tocopherols and carotenoids.
Some studies have shown a positive effect towards cutaneous sebum thanks to its emollient and sebum-reconstituting characteristics; moreover, it appears that the NON saponificabile portion also boasts an important positive action on skin trophism thanks to the stimulation of the reparative processes on the dermis and on the epidermis.
Among the other properties of extra virgin olive oil we recall the blandly laxative and the pain-relieving one given by the presence of oleocanthal.
