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How is extra virgin olive oil made?

How is extra virgin olive oil made?

Olive growers and producers here in Australia are gearing up to prepare for or begin this year’s harvest.  This means over the coming months, olives around Australia will be picked and pressed into fresh and healthy extra virgin olive oil.  Read on to find out just what goes into this process and why the processing methods make extra virgin olive oil so unique and so healthy.

Harvesting olives:

Olive trees are harvested once per year, and in Australia this happens in Autumn – usually beginning from March or April and lasting through until June. The way that olives are picked from the trees will depend on the grove and/or the grower and can range from hand picking through to the use of harvester machines that gently shake the trees delivering the olives into tractors.  The olives are then taken to a processing mill where they are washed with water and de-leafed (if needed) to remove any natural residue, dirt and twigs.

Crushing/pressing the olives:

After washing, the entire olive fruit (including the pit, flesh and skin) will be crushed/pressed mechanically to form a paste.  During this process the sharp pit of the olive will cut through the oil sacs within the olives, releasing the oil and putting it in contact with the skin and flesh of the fruit. This process is how the antioxidants from the olives infuse into the resulting oil, providing unique flavours and health benefits.

Decanting and separating:

Once the olives have been crushed to a paste, the paste is placed in a decanter which uses centrifugal force to separate the water/oil components from the rest of the fruit.  The oil is then placed in vertical separators – this stage removes the water and microparticles from the oil.

Storage, testing and bottling:

The oil has now been pressed, so it is time to store it before bottling and sending to customers or supermarkets.  The storage of EVOO is very important to the quality – best practice is to store in temperature controlled stainless steel tanks where the oil is not exposed to heat, light, or oxygen.  Before bottling, the oil is tested for chemical and sensory parameters to make sure it meets the requirements to be called extra virgin olive oil.  If the oil has no sensory defects and meets the chemical parameters, it can then be sent out for sale to customers directly, or to retailers to sell.

The final product:

The process outlined above uses no heat, chemicals or refining, meaning the final product is a healthy and natural oil that retains the health promoting antioxidants found in the olive fruit.