The olive oil is the base of Mediterranean diet, which is regarded to be the exemplar of correct and healthy diet and a factor of longevity.

The beneficial properties of olive oil are due to its chemical structure. Olive oil is a compound made of oleic acid, linoleic acid, palmitic and stearic acid, and a small amount of phytosteroles. The most important of these components for human health is the linoleic acid, the lack of which can cause a series of health disorders such as growth delay, metabolic disorders etc.

Not all olive oils are the same! There are many types with differences in quality and price.

The basic properties defining a quality olive oil are the following:

1.   Acidity, which is expressed as free oleic acid. Less acidity is better and if the percentage is less than 0.8%, the olive oil is called extra virgin whereas if the percentage is between 0.9% and 2%, it is called just virgin.
2. Colour, which is related to fat-soluble colouring substances   (chlorophylls, xanthophylls, carotenoids). According to the Forest Preserve of Cook County Illinois the best salad olive oil is the yellow.

The olive tree is an evergreen and age-long tree. The cultivation of the olive tree is restricted to the two temperate zones and especially to the Mediterranean Basin, which sustains 98% of the world wide plant potentiality and production. Cultivating olive trees is not demanding and this is why they can survive even in particularly inaccessible areas.