OLIVE POLYPHENOLS

Polyphenols are natural compounds found in plants. They have gained worldwide interest and the knowledge about the relationship between their consumption and health improvement is constantly growing. They show antioxidant and anti-inflammatory properties.

A greater or lesser presence and the families of these phenolic compounds are related to numerous variables, from the variety of the olive from which it comes, the soil in which the olive trees are located, the weather during the ripening time of the olive until the day of its harvesting, the harvesting, the processes of production, the storage and a number of factors that allow the oil obtained to have the level of excellence that the consumer deserves.

Mediterranean countries have lower rates of mortality from cardiovascular disease and cancer than Northern European or other Western countries. This has been attributed, at least in part, to the so-called Mediterranean diet, which is composed of specific local foods, including olive oil.

Traditionally, many beneficial properties associated with this oil have been ascribed to its high oleic acid content. Today, it has been demonstrated that many of the beneficial effects of ingesting virgin olive oil are due to its minor compounds, the so-called phenolic compounds.

Indeed, these phenolic compounds, provide not only flavor and aroma to the extra virgin olive oil, but also protection from deterioration caused by light and oxygen.

Virgin olive oil is produced by direct pressing or centrifugation of olives. The minor components of virgin olive oil are classified into different types, including phenolic alcohols: this group includes hydroxytyrosol ((3,4-dihydroxyphenyl)ethanol), tyrosol (phydroxyphenyl ethanol) and hydroxytyrosol glucoside, secoiridoids (elenolic acid or elenolic acid derivates), lignans and flavonoids (apigenin and luteolin).

The concentrations in virgin olive oils differ due to factors, such as the origin of the olive, degree of ripeness, milling process, etc. The most important secoiridoids present in virgin olive oil are the dialdehydic form of decarboxymethyl elenolic acid.

Spain, together with other Mediterranean countries such as Italy and Greece, has a long tradition of olive cultivation and olive oil production, with both the fruit and the oil being habitual components of the Spanish diet. Dietary intake of olive oil polyphenols in these countries has been estimated to be around 9 mg per day with a daily intake of 25–50 ml. of olive oil.