It happens when the olives reach the perfect level of ripeness, when their skin shows a change in colour. The level of ripeness helps produce oil with high levels of antioxidants (polyphenols) and a strong organoleptic fruity aroma. It is not permitted to collect olives that have been on the ground as some of the natural components of the soil contaminate the fruits with moulds and bacteria.
The rule about this phase of production doesn’t allow the olives to be transported inside sacks, as this would increase fermentation processed and modify the olives giving the oil a scent of “riscaldo”(sour/vinegary). The olives have to be transported to the mill within the 24 hours following the harvest exclusively in crates.
The olives delivered to the mill are stored in plastic bins with holes so that the air can circulate and the fruits don’t undergo any changes.
This process allows the removal of branches and leaves. At the same time the olives are washed so that soil and other impurities are removed from the fruits.
The milling is the crushing of the olives that produces a paste from which the oil is later extracted.
The olive paste is constantly stirred for about 40 minutes. Our mill does exclusively cold-press production (<27C) and, although this means slightly smaller quantities(5-10%), it allows to save some contents like Vitamin E while contrasting the number of peroxides and allowing the oxidation of polyphenols.
Extractions and separation:
The splitting of liquids and solids happens in the horizontal decanter where the paste is spinned. From the decanter we get the solid part (called pomace), made of stones, skin and pulp, and the liquid one (must), oil and water found in the olives. The crushed stones in the pomace are then recycled to make fuel for fire. Skin and pulp are used as feed for the groves owned by the cooperatives’ members. The liquid part is then pushed into a machine where the water is separated from the oil.
The oil produced by the Cooperative and given by the members to be commercialized is stored in the warehouse inside the mill. There are three dangerous factors that modify the characteristics of the oil: light, oxygen and critical temperatures. This is why the mill has an insulated warehouse where the oil can be kept at a temperature between 10 and 18 degrees and stored in small stainless steel containers (500 litres) after having been carefully transferred inside them in a single operation to avoid the contact with oxygen as much as possible.
The oil, after being naturally decanted and poured out, is ready to be commercialized. The Cooperative has its own bottling system. The sizes of packaging are: 0.25 litres-0.50 litres,0.75 litres in glass bottles; 3 litres and 5 litres boxes; 0.25 litres in ceramic oil jug.
Cooperativa piccoli produttori e coltivatori d’Ogliastra - Frantoio Oleario
Loc. Pizzu ‘e Cuccu Lanusei
Vietata la riproduzione anche parziale.
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