How Olives Are Processed Into Oil

Mediterranean people have struggled for millennia to extract oil from olive fruit. Today, highly sophisticated electronically controlled milling equipment quickly replaces the large stone grinders used for centuries to crush olive drupes.

While these traditional mills are still widely used, the sector’s continued efforts to achieve the optimal organoleptic characteristics and health properties have seen the technology used to produce olive oil change rapidly.

The technology behind the milling process

Olive oil quality has improved due to modern technology. Now producers can customize the transformation process by changing working hours, temperatures, atmospheric composition, etc.

“Without these advancements, we would not have the extraordinarily high quality of our olive oils,” Furio Battelini, the technical director of Agraria Riva del Garda, told Olive Oil Times.

Once the olives reach the mill, the leaves left over from the harvest are mechanically removed, and the fruits are washed.

1st step: crushing the fruit

Traditional mills smash olives using large grinders linked to a central column. Modern mills use hammer breakers, blades, or rotary disks to quickly process vast amounts of olives.

step 2: kneading the olive paste

In a modern mill, the freshly-produced raw paste is transferred into the kneader, also called a malaxer. The kneader is a tank equipped with blades that slowly stir the paste. 

The stirring process allows the blades to break up the water-oil emulsions created by the crushing. Furthermore, the process allows larger drops of olive oil to form, easing their separation from water, a crucial advantage for the final extraction.