Olive oil, the core of the Mediterranean diet
Distribution and classification
Olive oil, health, healthy fat, nutritional value, cardiovascular health, Mediterranean diet, EVOO, obesity
Olive is primarily grown in Spain, Italy, and Greece. Accordingly, in these countries it is mostly consumed. Nonetheless, two thirds of the European production is traded internationally, both within and outside the European Union.
According to the European regulation, the types of olive oil are the following:
- Extra virgin olive oil is the one with the highest quality. It is obtained from the first pressing of the olive in its optimal state only by mechanical methods. It is mostly composed of oleic acid (78%), a monounsaturated acid. Its acidity ranges between 0.2% and 0.8%, which means that there is a low fraction of free fat acids. Also, it contains a higher fraction of polyphenols, an antioxidant.
- Virgin olive oil is also extracted by mechanical methods, but using olives at no so optimal condition, i.e., they may have some external damage. Its acidity ranges between 0.8% and 2%, and has a lower fraction of polyphenols.
- Although not consumed by humans, lampante olive oil is made with olives that show external damages and are subject to physical and chemical processes. It is highly acidic and needs to be refined for its use in making other oils. Its acidity is over 2%.
- Once refined, lampante olive could be consumed but more often it is mixed with a percentage of virgin olive oil to obtain the category entitled ‘olive oil’, that is commercially presented under two labels, mild and intense olive oil. Its maximum acidity is 1.5% and has a minimal fraction of polyphenols.
- Lastly, olive pomace oil is made with the residual olive after undergoing mechanical processes. It is extracted with solvents and also mixed with virgin olive oil, and mainly used for frying. Its maximum acidity is 1.5%, but it has no beneficial properties as other olive oils with higher quality.
Italy and Spain are the largest extra virgin olive oil consumers in the European Union. Also, European countries such as Greece, Spain, Italy and Portugal, are by far the countries where olive oil is mostly consumed, for cooking, seasoning, sauteing, frying, braising and even preserving food.
Olive oil can be used to dress salads, or to fry (never reaching its smoke point). It stands as one of the best sources of fat in a healthy Mediterranean diet and can be a healthy substitute for other animal origin fats, such as butter. The recommended intake is between 1 to 3 portions (1 to 3 tablespoons).
Extra virgin olive oil presents several advantages. It is rich in healthy monounsaturated fatty acids, contains omega 9, E, A and K vitamins, iron, calcium, magnesium, amino acids, and contains large amounts of antioxidants with several beneficial health properties. In addition, it has anti-inflammatory properties, and has been widely described as a healthy food for prevention of cardiovascular diseases, being used in clinical trials with very positive results. Its high content on phenols has been also studied as a promising approach to prevent mental diseases such as Alzheimer’s disease.
Olive oil should be our main source of lipids due to its high nutritional properties and could be also used for cosmetics. Moreover, due to its physicochemical characteristics that make olive oil resistant to high temperatures, it should be considered as a primary option either for cooking or seasoning.
Finally, and contrary to what can be thought, consuming olive oil does not appear to
increase the likelihood of weight gain, and a moderate intake has been suggested to aid in weight loss.
There are several varieties of olives to make extra virgin olive oil. For instance, in Spain, the Hojiblanca variety is found in Granada and Málaga, in the South of Spain, while in the East (Catalonia), the sevillenca variety is predominant. Other varieties from other Mediterranean countries are Carpallese, Canino, Biancolilla, all of them in Italy, or Koroneiki and Conservolia in Greece, Branquita, Cobrançosa and Galega de Évora (Portugal). Each variety of olive produces a characteristic extra virgin olive oil with different flavour.
Not all types of olive oil have the same properties. For instance, pomace oil is extracted with solvents. Even though olive oil stands high temperatures due to its high smoke point, there is a risk of the formation of toxic compounds if we reuse the oil in frying.
Olive oil should be stored at temperatures between 15 and 18 °C, protected from light and heat, and well-sealed to avoid oxidation and rancidification. Its appearance should be liquid, oily and translucent, with no sediments.