The craft of turning olives into oil has been honed in the Mediterranean region over thousands of years, and techniques have been passed down from generation to generation. The process is truly a regional art. The method used in Greece is different from the one used in Spain, and each individual grower may have a unique way of tending the trees and producing the tasty liquid gold.
Olive trees must mature for several years before they produce olives. Careful pruning optimizes the number of olives a single tree will bear. A meticulous hand is necessary because it takes at least 5 kilograms of olives to produce one litre (about four cups) of olive oil.
Hundreds of olive varieties exist, but only several dozen are grown commercially around the world. Each type of olive has a unique taste. By combining different types the producer can create oil with an individual flavour. At Anthonij Rupert Wyne we have planted Corantina, Lecchino and Frantoio varieties.
The time at which olives are harvested also plays a major role in flavour and polyphenol content. The peak time is a short period right as the olives ripen. Olives are at their prime for only about two or three weeks. Healthy compounds then rapidly diminish over the next two- to five weeks.
At Anthonij Rupert Wyne we selectively harvest and press our olives between the months of April to June, ensuring that only perfectly ripe olives are picked at the right time to produce a fresh, flavorous and award-winning oil.
It takes quite a bit of work to coax oil out of olives. Harvesting is done by hand and involves combing the ripe fruit from the tree into nets with rakes.
Care must be taken when transporting olives from the trees to the processing plant. Olives are best carried in shallow containers so they don't pile up too deeply and crush one another. Any damage to the olives can trigger oxidation and fermentation, which create an "off" flavour. Olives should be processed soon after harvest because storage diminishes quality.
After olives are picked, any leaves, twigs, and stems are removed, and the olives are washed.
Then it's time for pressing. To get the best quality oil, the fruit must be pressed as soon as possible. Stainless steel rollers crush the olives and pits and grind them into paste.
The paste then undergoes a unique process called malaxation, a slow but thorough mixing process at a controlled temperature. This process allows the tiny oil molecules to clump together and concentrate.
The mixture is stirred for 20- to 40 minutes. Longer mixing times increase oil production and give the oil a chance to pick up additional flavours from the olive paste. However, the mixing also exposes the oil to air, producing free radicals that poorly affect its quality.
The mixture may be heated to about 27˚C (no more), which further increases yield but does allow some oxidation. This temperature is low enough to be considered "cold pressed."
Next, the paste is sent through a centrifuge (a compartment that is rotated on a central axis at extreme speed to separate materials). When the centrifuge spins, the olive paste remnants are pushed to the sides of the compartment cylinder while water and oil are extracted from the centre of the centrifuge. The oil and water are later separated.
Due to the speed at which the paste is spun a foamy layer of froth is formed on top of the olive oil, which is spooned off the top of the oil.
The solid material that remains after the extraction of the oil is called pomace, and it contains residual oil. Some manufacturers will use steam, hexane, or other solvents to squeeze more oil out of the pomace. This low-quality oil must be labelled as pomace oil.
Olive oil is usually bottled in a dark green bottle. This helps filter out harmful UV light which can cause deterioration of quality.
The 2015 vintage of the L’Ormarins Olive Oil will be released soon. Check our shelves when you next visit the estate.