The extensive orchards are grown in compliance with the EC regulation on the integratedfarming system.
Optimal harvest time goes from late September to late December. Fruits belong mostly to the Carolea variety, a typical cultivar grown in the province of Catanzaro.
Carolea is a vigorous and highly productive cultivar with an upward growth form. It is resistant to cold temperatures and drought. It produces good-sized fruits (> 4 g), elliptic in shape with a truncated base and a rounded tip. Oil yield is very high and reaches a peak in November; colour change is gradual and occurs late in the season, whereas the skin colour change is late and progressive.
Olive harvesting, exclusively from the tree in order to obtain high-quality oil, is performed mechanically through trunk shakers. As against hand harvesting, the use of mechanical aids has a considerable impact on lowering production costs. Nets are usually spread underneath the trees to catch the fruit and prevent contact with the ground. The fruit is then loaded into vented plastic bins (having a capacity of 250 kg) and sent to the home processing facility where they are pressed immediately.
Olives have to be processed soon after harvesting in order to produce the highest quality oil.
If too much time elapses between harvesting and processing, this may have a negative impact on the oil quality profile, with increasing acidity and organoleptic defects like musty and fusty flavour.
Once olives get to the processing facility, they are pressed in advanced, continuous-mode plants where they are processed by cold extraction through the following stages:
- defoliation : olives are loaded into a defoliator where leaves are removed before they begin the next;
- washing : over conveyor belts olives are taken to the washer where they are washed in cold water;
- crushing : olives are crushed into a paste;
- malaxation : the olive paste is funnelled to stainless steel pipes by means of a piston pump and fed to the malaxing vats. So the process step called malaxation begins, which involves stirring the olive paste slowly in order to promote the coalescence of small oil drops into larger ones and favours their subsequent separation by centrifugation. A short processing time and water temperatures below 26° C are fundamental prerequisites to obtain a high-quality final product. Instead, delayed malaxation and high temperatures may cause oxidation, which, in turn, promotes the degradation of antioxidant phenolic compounds and hence compromise the oil quality;
- extraction : this is achieved by centrifugation in 2.5 stages (during which olive pomace slurry and residue oil are obtained), with the addition of water at < 26° C to the olive paste. The residue oil is then funnelled into an outside extraction screw and stored in a silo;
- separation : the pomace slurry (a mixture of oil and vegetable water) is fed into vertical centrifuges: in one, part of the oil that may be present in the vegetable water is retrieved, in the other water is completely removed.
Product process of Azienda Agricola De Lorenzo