Olive oil

Among the world’s oldest and most valuable plant oils, olive oil is not merely a culinary ingredient but has historically been regarded as a functional product in fields such as medicine, cosmetics, and religious rituals. As a fundamental component of the Mediterranean diet, olive oil holds significant nutritional value due to its high content of unsaturated fatty acids and antioxidants.

Definition and Biological Origin

Olive oil is a natural vegetable oil obtained exclusively from the fruit of the olive tree (Olea europaea L. var. communis) through mechanical means without chemical processing. Harvesting olives at different stages of ripeness allows for the production of oils with varying flavors and chemical profiles. The olive tree is resilient to hot and dry climates but is sensitive to humidity during flowering. Due to its fruit structure, the plant can yield higher quality oil under mild stress conditions.

History

Although the exact origin of the olive tree remains uncertain, genetic evidence suggests it originated in the Eastern Mediterranean (particularly Syria) or Sub-Saharan Africa. Written records indicate that as early as 2000 BCE, olive oil was traded as a more valuable commodity than wine or seed oils. The spread of olive trees throughout the Mediterranean basin occurred through trade routes and agricultural expansion. During the Roman era, olive oil production and usage became systematic, with processing facilities established across the Mediterranean region. Olive oil was used for centuries as fuel in lamps, in religious ceremonies, for medicinal purposes, in soap-making, and in cosmetics.

Image of Olive Oil. (Pexels)

Global Distribution and Production

Today, approximately 23 million acres (9.4 million hectares) of land worldwide are dedicated to olive cultivation. These trees yield about 16 million tons of olive fruit annually, producing roughly 2.56 million tons of olive oil. 77% of global olive oil production is accounted for by Spain, Italy, and Greece. Spain, the largest producer, holds 36% of global production with an average annual output of 800,000 tons of olive oil. Most production still occurs on dryland farms using traditional methods, though Spain and some newer producers (Australia, Chile, Argentina) have recently adopted super-high-density planting systems.

Olive and Olive Oil Production in Türkiye

Türkiye has long been one of the key centers of olive production and lies within the Eastern Mediterranean basin, considered the ancestral homeland of the olive tree. Olive cultivation, with a history spanning thousands of years, is concentrated primarily in the Aegean, Marmara, Mediterranean, and Southeastern Anatolia regions. The Aegean Region leads Türkiye’s olive oil production, with local varieties such as Ayvalık, Memecik, Domat, Gemlik, and Nizip used for both table olives and olive oil.

Production Capacity and Development Process: The number of olive trees in Türkiye increased from 99 million in 2001 to 205 million by 2024, thanks to state incentives and sapling support programs. During the same period, total olive production rose from 600,000 tons to 3.75 million tons, an increase of more than sixfold. In 2023, production increased by 150% compared to the previous year, setting a new record in the history of the Republic.

Olive oil production reached 475,000 tons in the 2024/2025 season, while table olive production was recorded at 700,000 tons. With these figures, Türkiye has risen to become the world’s top producer of table olives and the second-largest producer of olive oil. According to Mustafa Tan, President of the National Olive and Olive Oil Council, this success was achieved by fulfilling the goals established in 2007: doubling the number of olive trees and entering the top two in global rankings. Türkiye ranks second in the world in terms of olive tree numbers, after Spain.

Harvest Timing and Quality Relationship: In Türkiye, harvesting is generally conducted using traditional methods, and the ripeness of olives is often not assessed based on scientific analysis. However, timely harvesting prevents natural fruit drop and enhances both yield and oil quality. Early harvesting, despite yielding lower oil quantities, produces more aromatic, low-acid, and polyphenol-rich extra virgin olive oils.

Processing Techniques and Modernization: According to analyses by expert olive oil taster and judge Paul Vossen, Türkiye is among the countries with high potential in olive oil production. However, it is still in a developmental phase regarding processing technology. In many regions, olive collection and processing still rely on traditional methods. Nevertheless, the increasing adoption of modern techniques such as early harvesting and cold pressing in recent years has significantly improved product quality. High-quality oils are now distinguished by fruity aromas and low acidity levels.

Sustainability and Climate Policies: Sustainable agricultural practices are essential to mitigate the effects of climate change and maintain production quality. Olive trees contribute to climate mitigation by absorbing carbon dioxide, making them one of the most climate-friendly crops.

Consumption Habits and Awareness: Olive oil consumption in Türkiye varies regionally. Per capita consumption is high in the Aegean and Marmara regions, while sunflower oil remains more commonly used in the Black Sea and inland areas. Compared to European countries, per capita annual olive oil consumption in Türkiye remains low (approximately 2 liters), whereas in Greece it reaches up to 26 liters.

As quality awareness increases, consumer interest is growing in oils produced through early harvesting, with low acidity and high polyphenol content. These oils demonstrate greater health benefits, particularly when consumed raw over salads and cooked dishes.

Exports and Competitiveness: Türkiye has occasionally targeted foreign markets but has struggled to compete with Spain, Italy, and Greece. Key challenges include insufficient branding, incomplete quality standardization, and limited adoption of modern production techniques. Nevertheless, Türkiye possesses strong potential to strengthen its position in the global olive oil market through its native olive varieties, climatic advantages, and growing production capacity.

Effects of Early Harvesting on Olive Oil

Early harvesting refers to the production of oil from olives collected before full ripeness. Oils produced this way are greener in color, have higher fruitiness, and possess richer sensory characteristics. They contain elevated levels of phenolic compounds and chlorophyll, which enhance the oil’s antioxidant capacity and extend its shelf life. Early harvesting also improves harvest performance by protecting fruit from environmental damage such as hail and storms. However, these oils may sometimes exhibit bitterness, a trait that diminishes over time.

Production Systems

In the traditional system, trees are planted at spacings of 7.5 to 18 meters, typically under dryland farming conditions, resulting in low yield per tree. Harvesting is done manually or with poles. This system is low-cost but low-yield.

In modern high-density systems, trees are planted at densities of 250–900 trees per hectare, with yields enhanced through advanced techniques such as mechanical harvesting and drip irrigation. In super-high-density systems, densities can reach up to 1,210 trees per hectare, enabling full mechanization. Compact varieties such as ‘Arbequina’, ‘Arbosana’, and ‘Koroneiki’ are used in these systems.

The advantages of the super-high-density system include early fruiting, lower harvesting costs, and production of high-quality oil. The main disadvantages are high initial investment costs and the need for technical expertise.

Processing Procedure

Olive fruits must be processed within 12–24 hours after harvest. Crushed olives, processed using stone mills or hammer mills, undergo a mixing (malaxation) phase at temperatures between 26–30°C. Subsequently, oil is separated from the paste through methods such as pressing, selective filtration (sinolea), and centrifugation. Two-phase centrifuges offer lower waste and better preservation of aroma and polyphenols compared to three-phase systems.

Oils are stored in stainless steel tanks for 1–3 months to allow sedimentation, then filtered and bottled.

Olive Crushed in a Mill. (Anadolu Agency)

Sensory Characteristics and Quality Assessment

According to the International Olive Council, a high-quality olive oil exhibits clear sensory attributes of fruitiness, bitterness, and pungency. Defective oils may display undesirable flavors such as fusty, muddy, vinegary, rancid, or salty. In good quality oils, fruitiness dominates, while bitterness and pungency vary according to ripeness.

Olive Oil Production Worldwide

Although olive oil production has historically been concentrated in the Mediterranean basin, it has now become a global agricultural and industrial activity. Worldwide, approximately 23 million acres (9.4 million hectares) of olive groves exist, producing an average of 16 million tons of olive fruit annually, which is converted into 2.5 million tons of olive oil.

Top 9 Olive Oil Producing Countries and Their Shares (2007–2016) (International Olive Council)

Main Producing Countries

Spain is the undisputed global leader in olive oil production. Approximately 2.42 million hectares of olive groves in Spain yield around 800,000 tons of olive oil annually. Between 2001 and 2002, due to poor harvests elsewhere, Spain alone accounted for 50% of global production. The most widely cultivated variety is ‘Picual’, which produces high-polyphenol, strongly aromatic oils from early-harvested fruit. However, production using late-harvested and ground-collected olives is also common, yielding lower-quality oils suitable for refining.

Italy ranks second in olive oil production. Approximately 1.43 million hectares of land are dedicated to olive cultivation, producing about 520,000 tons of olive oil annually. Production is highly regionalized; areas such as Tuscany, Puglia, Sicily, and Umbria are known for aromatic oils derived from distinct olive varieties. Italian production is largely artisanal, involving blending of different cultivars. Key varieties include ‘Frantoio’, ‘Leccino’, and ‘Coratina’.

Greece contributes approximately 17% of global olive oil production and has 1.03 million hectares of olive groves. The most common variety, ‘Koroneiki’, yields durable and aromatic oils with high polyphenol content. However, in some production processes, delays between harvest and processing can negatively affect oil quality.

Together, these three countries account for 77% of global production.

Other Producing Countries and Emerging Markets

Countries such as Tunisia, Türkiye, Morocco, Syria, and Portugal possess extensive olive grove areas but lag in yield and quality. Production in these countries is predominantly traditional, with limited numbers of modern processing facilities. However, recent efforts aim to increase production through mechanization and export-oriented policies.

New World producers include California (USA), Chile, Argentina, Australia, and South Africa. The rapid adoption of super-high-density planting systems in these regions has increased yields and reduced production costs. Compact varieties such as ‘Arbequina’, ‘Koroneiki’, and ‘Arbosana’ are used, enabling producers to reach full yield within 2–5 years.

Global Trends and Trade

In recent years, global olive oil production has increased at an average annual rate of 1.4%. Under dryland farming in arid and hilly areas, average yields are approximately 0.5 tons per hectare, whereas in irrigated and high-density systems, yields can increase up to tenfold.

The olive oil market is also characterized by quality competition. The European Union and the International Olive Council (IOC) have tightened labeling standards to combat fraud, linking classifications such as extra virgin to chemical analysis and sensory testing. The mislabeling of pomace oil as virgin oil has underscored the necessity of these controls.

Consumption and Exports

Per capita consumption is very high in traditional producing regions: 26 liters in Greece, 15 liters in Spain, and 13.5 liters in Italy. In contrast, consumption in the United States is only about 0.7 liters per person. Despite this low rate, the United States is the fourth-largest consumer of olive oil globally, importing more than 60 million gallons annually. This demand has spurred growth in domestic production in regions such as California.