However, the general method is beating. Stripping or carding method is used in hand-picking and a roller or brush is used in ground-picking. In the present day, machines are also made use of in olive harvesting (for beating and picking the fruits on the ground by suction equipment) as well. The method which requires the most labour in practice is the hand-picking method. This method by which a maximum of 9-10 kg olives may be picked ensures the production of the olive oil of best quality if the fruits are firm. 

In the olive oil culture, yet another tradition which has not changed for thousands of years is the method of oil extraction from the olives. The reason for this is that olive oil is obtained by passing the olives through a cold press and may be eaten without any chemical processes. Just for this reason, there is no difference between the olive oil extraction method employed in the Middle East in the present day and the one used some six thousand years ago: Olive are crushed into pulp and then this pulp is squeezed or passed through a press. And finally, oil is separated from the waste water of the olive fruit. Hydraulic presses started to be used once technology developed in the early 19th century. At present, besides hydraulic presses, such machines aimed at obtaining olive oil by centrifugal force without applying any pressure on the olive pulp. The most widespread one among them is the “continous system”. 

Continuous system is also called fully automated system. First, olive are sorted out by varieties. Olives dropped into the pit called “funnel” are stripped of their leaves by a machine and crushed and broken in a crusher (the machine finely crumbles the stone at 3.000 cycles. The pulp coming out of the machine is added with water upon stirring and kneading. Pomace and juice are separated. Oil and waste water are separated from the juice and the oil is taken into the filtering tank. Last sediments are removed and the oil is left into the settling tank. From here, natural oil is filled in kettles, cans and bottles. Pomace left of the oil is re-ground and used in making soap. Pomace sediment is called a pellet and used for fuel.

In order to obtain olive oil of good quality: Olives should be processed as soon as possible after the harvest. For olive is fermented if stored and this causes a degradation in the quality of the olive oil. However, in period when there is an “abundance” of olives, it may be required to store the olives. In such a case, olives stored without processing are usually stored in the form of heaps 20-30 cm high in well ventilated and cool warehouses. Natural olive oil goes under the following processes so that it may be of good quality: Olives are pick just in time and well cleaned in the oil mill without storing for a long time, settled in proper containers and kept in a cool and dark place.

Production of black edible olives 

Olive is an agricultural crop with so great an importance in terms of the national economy and nutrition of the people.

The edible olive sector is in a breakthrough in our country as well as all the world over. Construction of infrastructures employing new technologies in the recent years and the progresses in the sector in the forthcoming years shall create opportunities for our country to process olives of any quality required by the international markets and to be competitive. 

Black edible olive may be made out of any varieties of olives: However, products of better quality are obtained from the Gemlik variety olives with thick flesh, small stone and thin skin. 
Even if there are different methods in sweetenting the black olives, the processes from the harvest to the sweetening are all the same. Let us study such processes in a sequence. 

1. Harvesting and handling:

Olives must be harvested when the fruit has blackened and the flesh has become violet. 
Harvest is a significant factor affecting the quality of the black edible olive. Olives which are prematurely harvested fail to give fruits in dark black colour. Overripe olives which are harvested late easily softens and crushed in brine. Harvest must be carried out by picking the ripe fruits in lots, but not at a time. Picked olives must be handled to the processing plant in 20-25 kg woden or plastic crates which are not too deep and which do not damage the olives. 

2. Sizing and sorting:

Olive brought into the pickling plant go under sizing and sorting proceses. If the olives are too ripe, then they only go under sorting process. Sizing process may also be carrşed out once the olives have sweetened. 
Here, the objective of sizing is to separate oil olives with smaller fruits and that of sorting is to separate the damaged, bruised, infirm and soft olives from healthy ones. 

3. Washing:

Before olives are placed in fermentation tanks, they go under washing process in order to clean any dust, dirt, earth, mud, etc. on them. 

Olive tree and fruit: 

Scientific classification of olives

Kingdom Plantae
Division Magnoliophyta (kapalı tohumlular)
Class Magnoliopsida (iki çenekliler)
Order Lamiales
Family Oleaceae (zeytingiller)
Genus Olea
Species O. Europaea

Olive is a long shrub or an evergreen tree with dense branches, broad top which may reach a height of 10 meters. 

It has a large, distorted and bumpy trunk. As the tree ages, the smooth gray trunk gradually starts to crack. Crown of the tree wiens as the height increases every year. It is a perennial tree and may live approximately 2000 years. The crown is open and symmetrical in fertile land, but denser and rounded in infertile land. Shoots are gray in colour and almost triangular. 

Lanceolate, too short-stemmed, skin-hard shoots are lined in reciprocal couples. Leaves are simple, full-edged and slightly upturned on the edges. A leave is 20-86 mm long and 5-17 mm wide. There is a small spine at the tip of the leave. Upper surface of the leave is dark gren-gray and bare and the lower surface bluish-silver and covered with white sense silken fuzz. 

Olive tree blossoms in the spring. Its stone starts to harden and fruit to ripen in the summer months. Starting to change colour in September through November, olive first turns from gren to violet and then to black, thus ripening. This stage is called “variegation”. Harvest of the ripe olives continues from September through February. The quality of the oil to be obtained is closely related with how olives are picked. Olive oil of the best quality is obtained from the olives picked from their branches one by one. Olive is also picked by dropping on the ground or by suctioning machinery. Olive should be processed as soon as possible after harvesting. To do this, olives allocated to oil extraction are first subjected to defoliation and washing processes in automated machines. Then the olives are crushed in presses, thus ensuring oil to be extracted from the tissues of the fruits. Approximately 10 kilos of olives are used to extract a kilo of early-harvested olive oil. In other varieties, 7-8 kilos of olives are sufficient to extract a kilo of olive oil.