To obtain a quality olive oil, it is essential to carry out a good technique in each of the phases and processes of its elaboration.
The first phase starts with the harvest, it is essential here to collect the olive at the optimal time of ripening. All olive plants varieties produce excellent virgin oils-each with different flavour profiles- as long as they are healthy, milled the same day of harvest and stored properly.
There are several methods of harvesting. The most traditional method is called “ordeño”, used for collecting the table olives. It consists of carefully hand-picking the fruits, or in any case using a suitable rake. Another traditional harvesting method is called “vareo”, consisting of gently knocking the olive tree top with a long rod ( a fiberglass is nowadays used instead), in order to make the olives fall into plastic nets on the ground, which is previously placed under the tree around the trunk.
At present, the traditional methods coexist or have been replaced by mechanical methods. Generally speaking these new methods consist of mechanical tree shakers to cause the fruits to drop off.
The most important thing is to transport the olives in the shortest time possible to the mill, where the fruits are separated depending on the place they were collected, that is, from the soil or from the branches, so it is necessary to have two unloading points.
The olives must be brought to the mill within hours of harvest, to avoid oxidation and retain freshness, the shortest storage time is essential in the quality of the final product.
Once in the mill, the olive fruits are washed and separated from the branches with air. Other elements such as stones and mud, etc…. are separated in another washing process. Then the olive fruits are cleaned and are crushed in the crushing process to get a smooth paste.
The olive fruit extraction in a mill can be made in two different processes: pressing and centrifugation. The traditional method is pressing, where the paste from the pressed olives is whipped and mixed. Then the paste is transferred into a kind of flat baskets to be pressed using hydraulic presses.
In the centrifugation process the blended paste is placed into a horizontal centrifuge, which acts as a kind of press, to obtain three components: oil, vegetable water and pomace.
After the extraction of the oil from the centrifugal press the olive oil will be place for decantation or placed in a further centrifuge. These are the two main methods for allowing any residual sediment or water in the oil to be extracted. The vegetable water was contained in the olive. The pomace is the solid sediment which is composed of seeds, olive skin and olive pulp. There is nowadays another centrifuge process to obtain only two components from the olive: olive oil and solid waste (alperujo). After this process the oil is ready to go to the storage tanks.
To preserve the exceptional qualities of the virgin olive oil, a good storage technique must be carried out, using stainless steel tanks or vitrified olive oil presses, in darkness and tranquility, at mild constant temperatures. In a good cellar insulation become a must, so walls and ceilings must avoid high temperatures and foreign odors. It must have a heating system without foreign odors and keep a constant temperature, around 15-18ºC, which allows the olive oil undergo maturation free of oxidation. Another important aspect is darkness. In recent years, all these techniques, in the different stages have experienced a technological advance for a better efficiency in groves and in mills and in general in the overall harvesting in order to obtain this extraordinary.