The olive oil production process can be divided in four stages:
Before the olive oil extraction, an automatic leaf removal machine eliminates any residual leaves, sprigs or any other impurities from the harvested olives, and then the olives are washed with water to remove any other vegetable or mineral residues.
Olives are then briskly crushed to obtain a coarsely ground paste made of olive pulp and broken olive pits. Broken pits play an important draining role, making the separation of the liquids and solid components of the paste easier.
Just like dough for bread is kneaded, this operation involves a slow and continuous mixing of the olive paste and takes place in special kneading machines. This is a crucial stage for it allows the breaking down of the water-oil emulsions formed in the pressing stage and the gathering of oil droplets into larger drops. Thus the oil will separate easily from the solid paste.
This is the key phase in the entire process. Three components are extracted from the olive paste: pomace, vegetable water and olive oil. A common modern technique of extraction is centrifugation, which works on the principle of the different specific weight of each component. The olive paste is placed in high speed centrifuges that separate first the pomace from the liquid and then the oil from the vegetable water.