subject: Prompt Milling of Olives for Oil and Profit [print this page] There is archeological evidence in Greece that olive oil presses were used to extract oil from olives as long ago as five thousand years. If proper precautions are used, good quality olive oil can be obtained today by using the same sort of press that was used for centuries, if not millennia. Today there are newer techniques and technologies but one of the most important parts of making olive oil remains true. It is necessary to start making olive oil within a day or slightly more after picking the olives. Acids start to build up with longer storage of olives. This affects taste and lowers the price the maker of olive oil can charge. The country of Algeria is starting a monumental project to plant a million hectares (2.5 million acres) of olive trees. One of the key factors to success in producing high quality oil for export will be building a sufficient number of processing facilities with sufficient capacity near to the olive orchards.
Milling is the name for the entire process of extracting oil from olives. People have known for years that you need to grind the olives into a paste and that you need to press the paste to extract the oil. As science has progressed we have come to know that the oil is produced in what are called "mesocarp" cells in the olive. The olive stores oil in a vacuole called a lipovacuole so that every cell contains a tiny drop of olive oil. The point of the whole thing is to effectively extract as much of the oil as possible, separating it from the other structural parts of the fruit. The old saying that oil and water don't mix is true here because the oil can be separated from plant material and water by pressing and centrifugation (modern extraction) without adding chemical solvents. This entire process works with the old method but it is extremely important to wash the olives thoroughly before starting the process to remove all soil. Even a tiny amount will leave a taste, a "soil taste."
In the old method the olive is reduced to paste and the liquid in the paste is separated by the press. Decantation separates oil and water. Today a centrifuge can speed the later process and sterile machines can grind the olive to paste. An important aspect of grinding is to let the process last at least half an hour or a little more. This guarantees that the paste is well ground and for tiny drops of oil to coalesce into larger drops. It also allows fruit enzymes in the olive to act upon the mix which produces some of the aroma and taste unique to certain types of olive.
There are still advantages to using grind stones if properly cleaned. Much has to do with not letting enzymes in the nut and skin to act on the mash while its own enzymes do. In the end getting olives to processing promptly and cleaning thoroughly are the most important early steps.
A Practical Example
The Spanish company, Espacios Verdes, is planning to take part in the Algerian olive tree initiative. It will plant 1,500 hectares of which a third will be offered to private investors on a partial interest payment, partial sharing of production agreement. As part of this project the company will build an olive oil processing plant in Algeria. Having a processing plant close to the harvest will be crucial in the production of high quality olive oil.
Through its subsidiary, Desert Vert, Espacios Verdes will plant the Arbequinia olive on its project. This olive is especially adapted to a hyper intensive planting technique where 1,780 trees can be planted per hectare. The Arbequinia olive gives up twenty percent weight per volume of oil out of a much as 11,000 kilograms of olive per hectare. Because this type of olive starts to produce as early as three years instead of five, oil is being processed after the third year. This small brown olive can produce as much as 2,090 liters of high-quality oil known for its buttery texture and peppery finish.
The use of a modern facility by Desert Vert will help to assure production of high quality oil suitable for export and sale at premium prices. It has always been possible to produce olive oil from olives in many parts of Algeria. However, the lack of sufficient processing facilities has been a hindrance to the production of export quality oils. Even when there are facilities the facilities may not have to capacity to process large quantities at harvest time. Thus olives sit and wait, enzymes act on the fruit and acidity rises. The presence of a modern processing plant will make the difference between low grade olive oil sold locally and that exported at premium prices across the world.
The Desert Vert project is using an olive that originated in the Middle East. However, the arbequinia olive is named for a town in Spain near in the Mediterranean coast in Catalonia. When the company was in the early planning stages of its project it consulted experts at the University of Cordova in Spain. The question was what olive variety would be most suited to the soil and growing conditions in Algeria where Desert Vert is going to plant. The company was also interested in planting a vigorous olive variety and would be resistant to drought and to cold as these extremes could destroy in one season or one night the years of work in developing a productive orchard. The Arbequinia olive came out on top as a suggested variety because it produces well, has high quality oil, grows well and fast from cuttings, and is tolerant of environmental extremes including salty soil.
As the project progresses Desert Vert and its investors will profit from the production of high quality oil promptly extracted from olives grown in Algeria's million hectare plantation project. Prompt milling will be assured by Desert Vert's own processing plant.
