How Extra Virgin Olive Oil Is Made

How Extra Virgin Olive Oil Is Made
Extra virgin olive oil, simply put, is the juice of crushed olives.
There is evidence, across the Mediterranean and Levant of the production of olive oil going back for millennia. The typical image is of giant stone wheels, turned by donkeys, crushing olives into a paste which is then spread onto large rope mats and pressed, in a giant screw press, until the oil is literally squeezed out of the paste, filling large pottery amphorae.

Thankfully things have moved on and whilst olive oil remains the ‘juice of olives’ technology and modern standards of hygiene are at the forefront of today’s production.

Since the middle of the 20th century, most extra virgin olive oil is made using a centrifuge and not a press.

Here is how extra virgin olive oil is made in Nudo farmers’ oil mills now. 

At the olive harvest, the freshly picked olives are delivered to the mill the same day they are harvested. It is essential that they are pressed within 24 hours of picking for as soon as they are picked, they start to degrade.
When they arrive at the mill, the olives are poured into a sorting bin to remove the excess foliage, leaves and twigs which have been collected along with the fruit during harvesting. Although our mills’ technology has certainly updated the process from ancient olive stones, there is a still a ‘by hand’ aspect to it. Here you can see at Aleandri mill, extra foliage being picked out during the process.
The olives are washed and sent along a conveyor which removes any foliage that has been missed and ensures the fruit is clean and ready to be crushed. 
Next is the first step of extracting the oil from the olives. 
Most modern olive mills produce oil using ‘cold extraction’. The olives are not pressed to release their oil, but tipped into cylindrical metal crushers which, whilst slowly churning, crush the olives using a series of metal blades. The whole fruit is gradually turned into paste, which in turn passes into a centrifuge where the oil is separated from the pulp and the fruits’ water content, thus resulting (if the olives are of a high standard, not over / under ripe, diseased or infested) in three elements at the end of the process – extra virgin olive oil, the olive pulp or pomace and the olives’ water content. 

This is the time when the fluorescent green oil starts to flow and the olive farmer and miller separate off a quantity for tasting. Simple crusty bread is in Italy the traditional means of tasting new oil and nothing could be more perfect. 

But before the oil is tasted its other elements such as colour and bouquet are considered. 

The majority of Nudo’s Extra Virgin Olive oil is filtered. The exception being Olio Nuovo, the first of the year’s deliveries to customers. This unfiltered oil has a cloudy appearance caused by tiny particles of the fruit remaining suspended in the oil. These tiny flavour packed particles deliver the vibrant and robust flavour character and give the iconic cloudy green appearance unique to this oil. This is Olio Nuovo, bottled and delivered immediately after harvest, it is the freshest oil you can get and is a real seasonal treat.
The majority of extra virgin olive oils are filtered before bottling to remove the olive sediment. Filtering produces a translucent oil which some consumers prefer and removing the organic sediment means the oil lasts longer.
Filtering takes time to allow the particles to naturally settle. Once settled the oil is filtered through a cotton sieve to remove most of the remaining sediment, leaving a clear oil which is bottled.
This is why the oil From Your Tree is delivered in April, we send it out as soon as possible after it is produced, filtered and bottled.
Below is ‘pomace’ the leftovers from the olive stones, flesh and skin. This along with the olive tree foliage is used for alternative energy sources and compost. 
There is a great deal of research going into finding further uses of the pomace including using it as animal feed.