Monday, 11 November 2013



How is extra virgin olive oil being made. It is necessary to underline that we purposely deal with virgin and extra virgin olive oil, for only these two types, according to law, can be obtained through a mechanical “pressing” of olives.

All other types, including the one simply called “olive oil”, undergo chemical treatment, normally called “refining” treatments.


Everything starts with the olives                     

The types of olives, Cutlivar called, affects the result of extra virgin olive oil obtained
Of course, it all starts with olives, people could say!

Yes, its’ true, however in times of frauds, food sophistication of all sorts, it is good to remind ourselves that extra virgin olive oil can be obtain only and exclusively from olives!

There are so many different types of olives. Every type can produce a different kind of oil with a specific character and “personality”. In technical slang language it is called “fruttato” (flavor) and there are many kinds, but here in “Oliving” we prefer using the word emotions: every olive gives a different emotions!

This historic fruit, throughout the centuries, has entered into the most different Italian regions and has adapted itself to all types of climate and conditions. The ripening process of olives reflects the great variety of existing types.

Some olives are ripe by the end of August, others in September, and still others in October, November and December. There is no precise rule to determine when the olives are ripe to the right point. When the process nears the external peel of the olive gets quickly darker> It is a process called darkening. It is not a rule, however the best quality of oil is obtained when the olives are picked at the beginning of the darkening process.
Unfortunately it corresponds to the moment when the yield is the lowest, if compared to when the olives are very dark (almost black).
We already stated that the quality of oil does not correspond to the quantity!                          



Harvest and storage 


There are different ways of picking the olives: by hand, with instruments facilitating the collection ( a sort of automatic rake), shakers (machines which shake the tree causing the olives to fall on the net).

Except from the picking by hand which remains undoubtedly the best method ever, yet, unfortunately, the most costly, it is quite difficult to define which are the actual disadvantages of other methods. To try understanding the critical points related to the collection of olives we propose a test which you can easily make at home.
Take a ripe apple, press the peel with one of your fingers. Sometime later you will notice that where you pressed the apple with your finger the color will darken. It is due to the fact that by pressing the skin of the apple you have accelerated the chemical processes of decay of the apple. Exactly the same happens with olives.
The more the collecting method mishandles the olives, the more they will reach the olive mill in poor conditions. This, coupled with the time of storage may have a bad influence on the quality of oil.

However, it cannot be said that only by hand picking the olives good quality oil can be produces! If the collection is carried out by using the brain on top of the use of hands … it is possible to obtain some very good quality of oil also with other methods which rely on some mechanical devises.                                 


After the harvest and before being crashed, olives must be stores in some appropriate containers.

The storage is definitely one of the most critical passages of the entire process. Even when olives are of the best quality and have been properly picked, a bad storage could totally compromise the quality of the oil by introducing a series of defects which can be easily perceived even by people who are not expert in the field.
The reason which lies at the bases of this critical moment is quite simple: olives start to decay (oxidation, fermentation, etc.) from the first moment following the harvesting. This decay process increases with the passing of hours, with the change of temperature, and the pressure suffered by olives stored in large quantity. The following are some of the rules which producers of high quality oil normally follow:

1. Avoid storing olives for a period longer than 24 hours ( high quality oil producers normally press the olives within 12 and 24 hours from harvesting time)

 2. Avoid using containers which are too tall so as to eliminate the pressure exercised by olives on top on olives at the bottom.

 3. Keep containers on a ventilate, cool area and very protected from the light.


Defoliation and olives washing

Before being crushed, the olives are washed to remove any residue of soil At the oil mill, olives are first of all cleared from all leaves. Actually, not all leaves are left behind while picking olives. This is by no means a problem, since leaves in small quantity contribute to the color of oil and also to its aroma.

 Nevertheless, some producers particularly “obsessed” with quality reach the point of selecting every single olive which enters the mill eliminating whichever residue which may even slightly compromise the high quality of oil.
It becomes clear that an extra virgin olive oil of this type will unavoidably be very expensive ( however, most likely, very good also!)




There are many kinds of crushers, with hammers, with blades, with discs, but certainly the best known is the mills grinder After having been washed, olives are ready to be literally crushed.
In people’s imagination this is the moment when oil is actually produced. Yet it is not so. In this phase olives are only crushed (pulp and seed) so as to facilitate the extraction of oil which will take place in following phases.
In the picture you see what is perhaps the most ancient method of crushing: the grindstone.
Nowadays such methods still exist, however it has been substituted by and large by other mechanical systems such as hammer crushers, or blade crushers, etc. But it is nice to stay with the ancient and more poetic method of the grindstones. The goal remains always the same; crushing the olives.




The mixing is the process where the olive paste obtained by crushing the olives is mixed for about an hour What is left with olives after the crushing is a kind of dough which has precisely to be “blended” (kneading) in such a way that separation of molecules of water from those of oil may be favored ( they were mixed in the previous phase). This is a fairly long part of the whole process; it ranges from forty minutes to an hour.
The dough must be kept at a stable temperature of approximately 27 Celsius degrees. It is this phase which gave the name “cold pressed” to the oil. The expert eye of the mill operator will determine when the dough is ready and that is when on top of the dough he starts seeing tiny drops of oil which can become visible.

 A curiosity: there are producers who collect ( with difficulty) the oil which appears on the surface of the dough. This type of oil is therefore called “protruded” . Few produce it and it is obviously most expensive, nevertheless it is definitely worth the expense!

One last thing: if anybody happens to stop at an oil mill while the dough is being processed, most likely they will be quite reluctant to show it to you … Not for lack of kindness, but simply because in all the different moments of the processing of oil, contact with air should be strictly avoided.




Once the dough is ready it enters inside a “decanter” that has a centrifugal force which separates the solid elements (sansa) from the liquid ones (water and oil). The sansa is often used to obtain another kind of oil through a refining process ( sansa oil) or made into fuel.

The oil is separated from the water and the olive solid parts For curiosity sake it must be also said that the centrifugal system is not the only one to get the oil out of the dough.

 The ancient way was that of inserting the dough inside containers shaped as discs, made with vegetable or synthetic fibers. Then, with great pressure the oil was squeezed out of the containers. It has become very rare to still find such system.

In order to bring the process of extraction to completion it is necessary to totally separate water from oil. To do it, another type of vertical-axis centrifugal force is being used.  Thus oil is being finally obtained!

It won’t be limpid and clear as we are accustomed to taste it.
Indeed there will still be some minute particles of solid matter which have not totally eliminated in the previous phases. It is enough to allow the new oil to rest for some days so as to allow these particles to be deposited at the bottom of the container.

For purely esthetical reasons, however, oil is normally being filtered in many ways so as to make it clear as we are accustomed seeing it.





Concluding, oil is being stored in stainless steel containers which is perhaps the most suitable material to guarantee its conservation.
These containers will be of different sizes according to the need.

Those producers who choose a quality wise objective normally substitute the amount of air remaining between the cover and the oil with some inert gases such as nitrogen.

This way the oxidation process is avoided. In a second moment oil will be bottled in a more or less automatic way, according to the volume of production.


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