In the biological farm I Carusi the harvest of olives develops with the traditional technique called “brucatura” (or grazing): we “swipe” our fists among the twigs (we sometimes use a rake to reach the higher twigs) and we make the olives fall dawn on some clothes which are spread out on the ground and then we harvest and transport them in some jute sacks.
This is undoubtedly the best method of harvesting able to offer an extra-virgin olive oil with an absolute quality because the olives are harvested once in a process, without any damages to the plant that could compromise the productivity of the next year.
Moreover, the olives harvested with the grazing technique are cleaner (this reduces the microbial load on the peel and consequently reduces the presence of hydrolytic and oxidative enzymes of bacterial and fungal origins) and they are not damaged.
The olives are stocked under a canopy in order to not to be affected by the increase of temperature, poured in a hopper and then brought to the defoliator and to the washing machine where they are deprived of all the impurities (leaves, twigs, dirt, etc.)
After the washing, the olives are ground in a mill through the use of some knives and hammers that are able to produce a greener oil, rich in phenols.
This process develops indoor not to make the volatile substances vanish because they are very useful – like the polyphenols that help the conservation of the oil – and away from the oxygen because it oxidises the product generating the peroxides.
The dough produced is kneaded in some tanks, for about half an hour, at a temperature of 25-27°C.
The pressing and separation
After the kneading, the dough is brought to another tank where it is kneaded and diluted with the same water produced by the olives without any other addition, in fact the normal water should affect the last phase of separation of the oil from the water. After this last kneading the bough is pushed into the decanter that extracts the residual oil by centrifugation.