Cold-pressed olive oil is so valuable that it was hailed as the healthiest fat on Earth. It is also called extra virgin olive oil. It is usually processed under a temperature of at least below 81 degrees Fahrenheit to achieve its quality and be certified as the so-called “extra virgin”.
Olive trees bear a fruit called olive, it is harvested by hand or by machine. Olives must be harvested with no bruises or few bruises only to ensure their quality. Those harvested olives must be delivered to the plant immediately to prevent them from oxidizing, which means if it oxidizes before becoming a final product, its antioxidants are already gone.
After being delivered to the plant, the first thing manufacturers must do is wash the olives thoroughly and delicately. All dirt, twigs, insects, and leaves must be removed for quality assurance.
The cold pressing process is a requirement for olive oil to be certified as extra virgin. Olives should be pressed at a strictly monitored temperature, turning them into a paste form. If exposed to the wrong temperature, the olive paste may react to the free radicals completely affecting its taste and may lose its certification as being an extra virgin, that is what they are trying to avoid.
Water will be added to the olive paste, which they call the malaxation process. When the water is being added slowly, pushing the oil molecules together as we all know that water repels oil. This process requires constant stirring until all the oil clumps together to make the extraction easier.
In the last process, the mixture will be transferred into a container called a centrifuge and shall be rotated on an axis thus separating the olive oil and water. Again, this process shall be made on relatively low heat. The mixture left after the process is called pomace, which still has some oil, can be extracted again depending on the manufacturer but for a different variant of olive oil.