Pick, wash, crush, stir and spin. Filtering is optional.
This is how olive oil is made; simple and pure. But for this very reason it is so difficult to make. Unlike wine, there is no room for fixes. There is no primary nor secondary fermentation. There is no ageing in oak barrels. There is absolutely no way to hide any flaws, what you get is all there is.
Since olive oil is simply the olive juice, the fruit quality is what primarily dictates the final product quality. This is in turn influenced by the terroir and a number of factors which include irrigation rate, harvest timing and climate (frost, drought, etc).
An olive tree can be fix planted at the age of two, and usually blossoms and bears fruit three years afterwards. Six years after fix planting, the olive tree starts to enter the full bearing period; under normal management, the full bearing period can last for hundreds of years.
In order to make good olive oil the olives need to be harvested while still green. In the Old World (Europe) the harvest takes place in late October or early November. Mass low quality olive oil producers harvest the olives in January.
The olives are either hand-picked, or collected via the “tree-shaking” method using a tractor or other tools that reach the olives from the ground such as sticks or poles with a rotating blade at the end. Large low quality olive oil producers may harvest using large farming tractors that encompass the entire tree, similarly to what is done to wheat.
Our oils are all hand picked because to produce high-quality oil the olives must be harvested without breaking the fruit skins and we only work with green olives, the unripe olive fruit, which are very tightly attached to the tree and need to be removed one at a time or using “combs”. The olives are reached using ladders and are dropped over nets that cover the ground and then placed in crates and sent to the mill.
The fruit should be taken from the farm to the mill as quickly as possible and processed within 12 to 24 hours of harvest maximum. Our oils are normally processed about 3 hours or less after the harvest. Cheap olive oil is usually processed days after the harvest and sometime even weeks if the olives are transported to different locations.
Most mills pass the olives over a vibrating screen and blower that removes leaves and other debris and then wash it with water. The extra moisture from washing can reduce extraction efficiency because water/oil emulsions form and the oil experiences a reduction in bitterness, pungency and fruitiness – all positive attributes.
The washed olives are then passed through a crusher and turned into a thick paste which includes the olive skin, flesh and pit. A few exceptional producers go through the trouble of de-stoning the olives prior to crushing for a very distinct and pure oil. The Origini olive oil in our collection is among these rare folk.
Traditional olive mills use a pair or trio of huge stone wheels which go around in circles crushing the olives. In the past these wheels used to be powered by animals and although picturesque, the olive paste is exposed to air which leads to oxidation and decreases the oil quality.
The paste is then introduced into the Malaxer, which consists of a large cylinder with blades that keep stirring the paste very gently so that all the little droplets of oil come together and form larger blobs. The malaxer needs to be used very carefully and run for about 20 minutes maximum, any longer will form larger blobs of oil and thus higher yield, however at the expense of quality.
After the malaxer the olive paste enters into the Centrifuges, which are very noisy devices that spin the paste in a nearly vacuum environment so quickly that the oil (being lighter) separates from water and the solid particles from the paste.
Traditional mills use the olive press; they place the olive paste into malleable fibre discs, stack them up and then apply extreme pressure so that the oil is squeezed out of the paste and falls one drop at a time. Again, it sounds very romantic but the exposure to air significantly decreases the oil quality. The vast majority of olive oils are centrifuged and not pressed – so whenever you see the words “First Press” in the label of an olive oil bottle beware that it is probably not true but only there for marketing purposes.
When the oil comes out of the centrifuge it perfumes the entire mill. The smell of fresh olive oil is truly heavenly, and if it is made from green olives (as ours is) it has an incredible deep green colour (like spinach juice). The colour comes from the tiny particles of olive flesh that still remain in the oil and although making it look great, these tiny particles will degrade rather fast and thus affect the oil. Hence why filtering is important (you may consume unfiltered olive oil, but it really needs to be fresh).
Modern mills filter olive oil using decanters and traditional mills use pass the oil through cotton.
After filtering the oil is stored in large containers filled with an inert gas to keep the oil away from oxygen and preserve its quality until it is bottled. Fresh oil will still be quite green even after filtering, but it quickly turns golden which is perfectly fine. The colour of olive oil gives absolutely no indication of quality.
What remains is a brown paste made out of crushed pits and worked olive flesh. The Italians call this paste sansa and use as fertiliser for the trees.
Large producers will take the sansa to factories where it is chemically refined to produce olive-pomace oil. Sometimes these producers will add a little drop of extra virgin olive oil to this chemically processed oil and will call it olive oil. This is really bad olive oil and you should definitely not buy it unless you fancy eating oil made from something that seriously looks like excrement. No kidding.