There are many variables underlying an extra virgin olive oil, which can’t simply be quantified. Each blendmaster knows and has learned while “in the field” that the right level of ripening of the olives is essential to the aromas and flavors of the extra virgin olive oil.
In fact, the same olive can have very different characteristics depending on its growth phase. As a result, the harvesting period from the tree is chosen with the utmost care, and always depends on the oil being produced. First of all, it is important to know and be able to recognize the four ripening stages for olives: the herbaceous stage, veraison, full ripeness and over-ripeness.
The herbaceous stage generally starts towards the end of August, although this is highly dependent on the year’s climate and area of cultivation. In the first stage of ripening, the fruit has a bright green color and hard flesh which contains little oil. With the start of veraison, which is usually in mid-October, the olive becomes bigger and softer, rich in oil and a color tending towards purple.
The fruit harvested at this point in the ripening process produces an oil rich in precious antioxidants (polyphenols), with characteristic fruity, bitter and piquant notes. While a very different oil is obtained at the end of veraison, when the olives are harvested with intensely purple skin. This more mature fruit produces sweeter oils. Beyond a certain degree of ripening, however, the olives become dark brown and start falling to the ground, increasing enzyme degradation and contact with damaging microorganisms.
As you can see, the identification of the right degree of ripening greatly determines the taste of the oil. This is why the quality of an oil doesn’t just come about by chance.