How is olive oil made?
Olive oil has a fascinating history and is produced in various ways: from traditional artisanal methods to modern techniques. On this page, I will take you through this process, from the past to the present, showing how olive oil is made.
You will discover how olive oil was traditionally pressed, as my grandfather used to do, with a love for the craft and the simplicity of manual labor. I will also show how modern technology has changed the production process – where traditional presses have been replaced by innovative methods.
The famous "cold-pressed" olive oil is known worldwide for its unique taste, health benefits, and versatility. But what makes the production process of high-quality extra virgin olive oil so special? It all starts in the olive groves, where the careful harvest and processing are crucial for achieving an acidity level of no more than 0.8%.
In this explanation, I focus on the best olive oil: extra virgin. I will leave out other types, such as refined or regular olive oil. Step by step, I will guide you through the craftsmanship and innovation that have made the countries around the Mediterranean so famous.
Picking and harvesting
The production process for high-quality olive oil starts at the foundation: the careful selection of olives. For the best extra virgin olive oil, only healthy olives are harvested, often sourced from organic orchards.
The timing of the harvest plays a crucial role in the quality and flavor of the oil. An early harvest, usually between October and November, produces olive oil with a more intense, fruity flavor and a high antioxidant content. This olive oil is favored by connoisseurs for its complexity and healthy properties.
Later in the season, from November to February, the olives are fully ripe. They take on a darker color and contain more oil, resulting in a milder flavor and a higher yield. Both harvest times have their unique characteristics, but the choice depends on the desired end product.
There are various types of olives that influence the flavor of the olive oil. For example, the Arbequina olive, typical of Spain, produces a mild, fruity oil with a slightly nutty flavor, while the Picual olive, originating from Southern Spain, produces a more robust and bitter oil with a higher antioxidant content. The Koroneiki olive, which is common in Greece, is famous for its grassy flavor and strong aromatic properties.
The traditional olive harvest
In earlier times, harvesting olives was done primarily by hand – a labor-intensive process that ensured the quality of the olives. This artisanal work, often carried out by families and seasonal workers, was known as "hand-picking" and required a great deal of attention and dedication.
Manual harvesting brought significant advantages, such as minimizing damage to the olives. This was essential for producing high-quality olive oil with a refined flavor and low acidity.
Traditional harvesting techniques:
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Hand-picking:
In manual harvesting, workers picked the olives directly from the branches with their hands or simple tools like rakes or combs. This method was ideal for ripe and fragile olives, as the risk of damage was low. This was often done in the early morning, at low temperatures, to preserve the flavor and quality of the olives. -
Sticks to shake branches:
With this method, long sticks were used to lightly beat the branches, causing ripe olives to detach and fall onto the ground or into nets. Although this process was faster than manual picking, it could cause slight damage to both the olives and the tree. -
Nets on the ground:
Nets were placed at the base of the trees to catch olives that fell naturally due to ripening. Although this was less labor-intensive, it could affect quality because overripe olives lay on the ground for longer, which promoted fermentation. This method was often combined with hand-picking or stick-shaking to gather all the olives. -
Selective harvesting based on ripeness:
Great attention was paid to the right moment of harvest. For high-quality olive oil, green, unripe olives were picked early in the season. These olives produce an intensely flavored oil with a high antioxidant content, but the yield is low: approximately 10 kilos of olives for 1 liter of oil. Ripening, darker olives provided more oil (approximately 5 kilos per liter) and were used for other applications.
"For 1 liter of early harvest green olive oil, 10kg of olives is required. For 1 liter of olive oil from fully ripened black olives, 5kg of olives is required"
Traditional olive oil pressing
After harvesting, the olives were taken to the oil mill or the traditional press. Here, olive oil was produced in an artisanal manner, without the modern technologies used today. The process was manual, labor-intensive, and consisted of a series of simple but effective steps.
Cold pressing means that the olives are crushed without the addition of external heat, which helps to preserve the aromas and nutrients (such as vitamin E and polyphenols). The process must not exceed 27°C to prevent the oil from oxidizing and the taste from changing. This is why extra virgin olive oil is praised for its superior quality, as the oil is extracted directly from the olive without heating.
1. Crushing the olives
The harvested olives were first washed and then crushed along with their pits. This was usually done using large round stones – “millstones” – that were powered by people, animals such as donkeys, or later, windmills.
- The stones weighed hundreds of kilograms and rotated in a circle over the olives, grinding them into a paste.
- The grinding was done slowly to prevent overheating and to maintain the taste and quality of the oil.
2. Collecting the olive paste
The crushed olives formed a thick paste, which was transferred onto round mats made of braided fibers, such as hemp or coconut fiber.
- These mats were filled with olive paste and stacked in a press.
- The stacking process created some pressure, but the actual pressing followed in the next step.
3. Manual or mechanical pressing
A heavy press – often made of wood or metal – was used to apply pressure to the stack of mats.
- The press could operate via a lever or a screw mechanism.
- The pressure caused the juice, a mixture of oil and water, to seep out of the mats.
- The first drops of oil were the purest and were reserved for the highest quality, similar to what we now call extra virgin olive oil.
4. Separation of oil and water
The juice that came out of the press consisted of oil, water, and other particles. This mixture was collected in a vessel to settle.
- Because oil is lighter than water, the olive oil floated to the surface.
- This top layer was carefully skimmed or poured off, a process known as “decantation.”
- Sometimes this was repeated several times to obtain the purest oil.
5. Filtration and storage
After separation, the oil was sometimes filtered through cloths to remove any remaining impurities.
- The purified oil was stored in earthenware jars, amphorae, or metal containers.
- These storage methods protected the olive oil from air and light, which was essential to preserve its taste and quality.
- The jars were kept in cool, dark rooms to extend their shelf life.
The modern olive harvesting process
Since the time my grandfather picked and pressed olives by hand, much has changed in the world of olive oil production. Today, my family, including my uncle and cousins, harvests olives using modern techniques that are faster, more efficient, and more sustainable than in the past.
This approach marks an important step forward in the process, where tradition and innovation come together to produce high-quality olive oil.
In modern olive harvesting, various advanced techniques and machines are used to improve both the efficiency and the quality of the harvest. These innovative methods have optimized the process, allowing olives to be harvested faster and with less damage to the trees.
Below is an overview of the most important modern harvesting techniques:
1. Mechanical Shakers
Mechanical shakers are designed to grip the trunk of the olive tree and shake the branches vigorously, causing the olives to fall into collection nets.
- These machines significantly speed up the harvest and reduce labor intensity.
- They do not cause damage to the olive trees, even if they are older and sturdier.
- Shakers are particularly useful in orchards with older trees that are difficult to harvest by hand.
2. Automatic Harvesters
Automatic harvesting machines are mobile units equipped with special gripping arms or vibrators. They move along the rows of olive trees, picking the olives directly from the branches and collecting them in storage bins.
- These machines are particularly efficient in orchards where the trees are planted at regular intervals.
- They are increasingly being used in large olive groves, where they significantly reduce harvest time.
- However, the Sierra de Segura, a mountainous area, is difficult for these machines to access, which is why hand-picking is still often used there.
3. Nets and Vibrating Rakes
In steep or hard-to-reach orchards, vibrating rakes are often used. These rakes shake the olives loose from the branches, after which they fall onto nets placed under the trees.
- This method is ideal for areas where it is difficult to work with large machines.
- The use of nets ensures that the olives can be easily collected without being damaged.
- Shaking the olives with the rakes is less intensive than other mechanical harvesting methods, making it a good option for difficult-to-access orchards.
Modern olive oil production
In modern olive oil production, advanced techniques are used that significantly improve both the quality and efficiency of the production process.
Below is an overview of the most important steps currently applied in the olive oil production process:
1. Sorting and Cleaning
After harvesting, the olives are taken to the press or mill, where they are first thoroughly sorted and washed. This removes leaves, twigs, and other impurities, ensuring the olive oil remains pure. Removing unwanted materials prevents foreign flavors from affecting the oil during the production process.
2. Grinding and Crushing
The olives are then ground into a paste. This takes place in a modern mill, where both the flesh and the pits are crushed. Depending on the desired texture and flavor, this is done using stainless steel hammer mills or stone rollers. Grinding releases the oil and aromas, which influences the final flavor of the olive oil.
3. Mixing and Kneading (Malaxation)
The olive paste is then placed in a malaxer (mixing machine), where it is gently kneaded and stirred for 20 to 40 minutes. This process ensures that the small oil droplets coalesce into larger droplets, which improves the extraction process. Mixing occurs at a low temperature (cold pressing), typically not exceeding 27 °C, to minimize oxidation and maintain the quality of the oil.
4. Centrifugation or Separation
After mixing, the paste is placed in a centrifuge, where the oil is separated from the solids and water. Due to the high speed of the centrifuge, the light oil particles are pushed outward, while the heavier water and solids remain in the center. This results in an initial, pure olive oil extraction.
5. Filtering and Refining
The olive oil that comes out of the centrifuge is often filtered to remove any remaining impurities. Some producers choose to leave the oil unfiltered for a more authentic, "cloudy" texture, but filtering helps extend shelf life and ensures a clearer product. Due to our high-quality standards, our olive oil is always filtered.
6. Storage in Stainless Steel Tanks
The filtered oil is stored in stainless steel tanks, often under a nitrogen atmosphere. This prevents oxidation and protects the olive oil from light, air, and temperature fluctuations, ensuring that the flavor, color, and nutrients are optimally preserved. The tanks are often kept in cool rooms to further ensure quality. By creating ideal conditions, olive oil can be kept fresh for a long time before being bottled.
7. Bottling and Packaging
When the olive oil is ready for sale, it is bottled in dark glass bottles or tins. The dark packaging protects the oil from harmful light and air. After bottling, the oil is labeled and packaged, after which it is ready to go to the consumer.
Thanks to these modern processes, the quality of extra virgin olive oil remains consistent, while its healthy properties and authentic flavor are optimally preserved.
Pressing of the Saqura extra virgin olive oil
A good example of a modern olive oil mill is the one where the exclusive extra virgin olive oil Saqura is produced. This high-tech mill is located just outside the town of Arroyo de Ojanco in the beautiful Sierra de Segura. Here, my cousin, who works in the technical department, ensures that the mechanical press runs smoothly during the harvest season.
In the video below, the complete process from olive to olive oil is shown, step by step:
- Reception of the olives
- Cleaning of the olives
- Milling and crushing
- Mixing and kneading
- Centrifuging and separation
- Filtering and refining
Watch the video and discover how modern techniques contribute to the quality of extra virgin olive oil like Saqura.
Would you like to try the extra virgin olive oil Saqura yourself? Order this exclusive olive oil here.
