Extra Virgin Olive Oil Production

Italian extra virgin olive oil (EVO oil) is one of the most appreciated products in the world by lovers of good food and a healthy lifestyle, but those who know exactly how it is made are few. In this step by step guide you will discover how quality extra virgin olive oil is made.

The best way to find out all about extra virgin olive oil is to visit a production area, see the olives growing on the trees, breathe in the inebriating aroma of fresh ground olives, taste the oil fresh out of the centrifuge. Join one of our tours with tasting in the production areas of Verona.

1. Olives Harvesting

The harvest takes place in autumn. In Italy, depending on the area and the time of maturation of the olives can go from early October until early January.

Degrees of ripeness

2. Washing

After harvesting olives are washed with water to remove leaves, soil and other unwanted materials that could transfer impurities and a bad taste to the final product.

Traditional Method Vs Continuous Process

There are two methods for producing olive oil: traditional and the more modern continuous process. In many mills they still coexist and there are supporters of both ways and even hybrid solutions.

3. Milling

With traditional methods the olives are ground with large stone grinders that turn until they are reduced to a homogeneous paste.

With more recent methods, the milling of the olives can take place with hammers or grinders.

4. Gramolatura (Malaxing or churning)

In special containers the olive paste obtained in the previous step is stirred for a certain period of time. This process allows the micro droplets of oil that are released with the milling to aggregate into larger and larger drops. This facilitates the subsequent separation from the solid part.
In the most modern systems, crushing takes place under nitrogen which prevents any oxidation.

5. Pressing

This is the operation that separates the liquid part of the olives, consisting of a mixture of water and oil, from the solid part, fibers and remains of the pits.
It is at this stage the biggest difference between the traditional method and the continuous method.

Traditional Method

On special filtering discs made of a mesh of fibers (fiscoli) is spread a layer of olive paste. Many of these discs with their layer of olive paste are stacked on top of each other to form a column which is then placed in a hydraulic press. The olive paste crushed between one fiscolo and another by a very strong pressure releases all the liquids, consisting of the mixture of oil and vegetation water, which are collected in a special container below.

Continuous Method

The three constitutive elements of the olive have different specific weights. The oil is the lightest (if you pour the oil into a glass of water it will remain on the surface), the water is in the middle, and the solids are the heaviest. Leaving the olive paste in a container, with time the three components would spontaneously separate because of gravity which makes the elements deposit in layers according to their weight. The continuous method only accelerates this process.
The olive paste enters a special horizontal cylinder called decanter or separator. The cylinder rotating at high speed, separates the components of the olive paste according to their different specific weight: oil, water, solid residue (pomace).
The continuous method is more modern, faster and requires less manpower.

6. Centrifugation

6. Filtering

Freshly extracted olive oil often has a beautiful deep green color and is slightly cloudy due to the solid particles that are still inside it in suspension. Olive oil filtration removes these particles to give the olive oil a perfectly transparent appearance.
Filtering is an optional practice. Many producers bottle unfiltered olive oil. According to some, by filtering the oil, some of the intensity of the flavor is lost.
In any case, unfiltered oil will tend to become clear over time as the solid components will naturally settle to the bottom. Some consumers do not like having these deposits in the bottle which can cloud the oil again every time it is poured.

Attention!

A cloudy oil is often synonymous with freshly pressed and therefore very fresh oil. Some unscrupulous producers create this effect for marketing purpouses by adding substances that stay in suspension much longer. If your oil is still cloudy many months after production, it could mean that it has been adulterated.

Large industrial producers

These are the basic steps in olive oil production, what you will see when you visit a small, traditional mill. Larger, industrial producers will also use different methods, adding different substances at various stages of production in order to control production and ensure a consistent taste to the olive oil. The addition of chemical solvents to the processing residues or much higher processing temperatures that make the oil more fluid, can increase the yield of olives by a few percentage points. By doing so, however, oils loose many of their antioxidants, lacking of flavor or with many defects in taste.
Temperature is also fundamental for the quality of olive oil. Traditional methods ensure that during milling, stirring and pressing, the temperatures of the olive paste never exceed 80°F (27°C). Faster, industrial methods tend to produce higher temperatures that damage the flavors of the olive oil. The final result will obviously be different, less complex and intense.

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