What This Article Explains

How Olive Oil Is Made

Making olive oil follows a clear sequence from fresh fruit to finished oil:

Harvest → Clean → Crush → Malax → Separate → Clarify → Store → Bottle

1. Harvesting: Olives are picked at a chosen stage of ripeness and taken to the mill.
2. Cleaning: Leaves, twigs, dust, soil, stones, and other field material are removed.
3. Crushing: Whole olives are crushed into a thick olive paste.
4. Malaxation: The paste is slowly mixed so small oil droplets can combine into larger droplets.
5. Separation: The oil is separated from water and olive solids using physical extraction methods such as pressing or centrifugation.
6. Clarification: The extracted oil may be settled, racked, filtered, or otherwise clarified.
7. Storage and Bottling: The oil is stored under protective conditions and then bottled for distribution and use.

The exact equipment, timing, temperature management, olive varieties, and storage practices vary among producers. These decisions can influence an olive oil’s flavor, aroma, bitterness, pungency, freshness, and stability.

1. How Are Olives Harvested for Olive Oil?

Olives are harvested at a chosen stage of ripeness and transported to the mill for processing.

Olive oil begins in the grove. Producers harvest olives once each year, generally during the autumn harvest season in Mediterranean growing regions.

Harvest timing matters because olives change as they ripen. Early-harvest olives are often greener and may produce oils with more pronounced herbal, peppery, bitter, or pungent notes. More mature fruit can produce a softer, rounder oil and may yield more oil by weight.

Olives may be harvested by hand, with hand-held combs or electric harvesters, with branch shakers, or with mechanical tree-harvesting equipment. Nets are often placed below the trees to collect the fruit and help keep it off the ground.

For quality-focused olive oil, the goal is to protect the fruit from damage and get it to the mill promptly. Bruised, overheated, or poorly stored olives can develop undesirable flavors before milling even begins.

2. How Are Olives Cleaned Before Milling?

Before milling, olives are cleaned to remove leaves, twigs, dust, soil, stones, and other field debris.

Once the olives arrive at the mill, they pass through a defoliator that removes leaves, twigs, and other field material. The fruit is then washed to remove remaining dust, soil, stones, and debris.

Cleaning the olives does not make the oil extra virgin on its own, but it is an important part of a hygienic milling process. Removing foreign material before crushing helps preserve a clean flavor profile and protects milling equipment.

3. How Are Olives Crushed Into Paste?

Whole olives are crushed into a thick paste containing olive skin, pulp, water, pit fragments, and tiny oil droplets.

After cleaning, the olives—including the skin, pulp, water, and pit—are crushed into olive paste.

Modern mills may use hammer mills, disc mills, or knife mills. Traditional stone mills can also crush olives, although they are less common in large-scale continuous systems.

Crushing breaks open the olive cells that contain oil. At this stage, the oil is present as small droplets distributed throughout a mixture of olive pulp, vegetation water, skin, and pit fragments.

4. What Is Malaxation in Olive Oil Production?

Malaxation is the slow, controlled mixing of olive paste after crushing, which helps small oil droplets combine before separation.

The olive paste moves into a malaxer, typically a temperature-controlled stainless-steel tank that slowly mixes the paste.

As the paste is mixed, smaller oil droplets combine into larger droplets that can be separated more efficiently from the olive solids and vegetation water.

Malaxation time, temperature, oxygen exposure, olive cultivar, ripeness, and milling conditions can all affect extraction yield and the finished oil’s sensory profile. Producers balance extraction efficiency with the preservation of fresh aromas and desirable olive-oil compounds.

Water is not what defines malaxation. Depending on the milling system, limited water may be used during later separation stages, while some modern systems use little or no added water.

5. How Is Olive Oil Separated From Water and Olive Solids?

Olive oil is separated from water and olive solids through physical extraction, traditionally with presses and more commonly today with centrifugation.

After malaxation, the olive paste contains oil, vegetation water, and solid olive material. The next stage separates these components.

How Does Traditional Olive Pressing Work?

Traditional olive pressing uses physical pressure to separate liquid from prepared olive paste.

Traditional olive mills used hydraulic presses and fiber mats to squeeze liquid from the paste. This is the origin of the familiar phrase “cold pressed.”

The liquid obtained from pressing still contains both oil and water, which must then be separated.

How Does Modern Centrifugal Olive Oil Extraction Work?

Modern olive mills commonly use centrifugation to separate olive oil from vegetation water and olive solids according to differences in density.

The olive paste enters a horizontal decanter centrifuge, which spins at high speed to separate the oil from olive pomace and vegetation water.

A vertical separator may then further clarify the oil by removing traces of water and fine suspended material.

A centrifuge does not press the oil from the olive paste. Pressing and centrifugation are different extraction methods, even though both are used to separate oil from processed olives.

6. Is Olive Oil Filtered After Extraction?

Olive oil may be settled, racked, filtered, or clarified after extraction to remove suspended olive solids and residual moisture.

Freshly extracted olive oil may contain suspended olive particles and small amounts of residual moisture. Producers can manage these through several methods:

• Settling allows heavier particles to fall naturally to the bottom of a storage tank.
• Racking moves the clearer oil away from settled sediment.
• Filtration removes fine suspended solids and residual moisture more quickly.

Filtered and unfiltered olive oils can both be high quality. Filtration is not what makes an olive oil extra virgin.

Removing sediment and moisture can support stability during storage. Unfiltered olive oils may look cloudy and can offer an especially fresh, rustic appearance, but they generally require careful handling and timely consumption.

7. How Is Olive Oil Stored and Bottled?

After extraction and clarification, olive oil is stored under protective conditions before being bottled, commonly in dark glass or tins that help limit light exposure.

Before bottling, olive oil can be stored in stainless-steel tanks designed to protect it while awaiting packaging.

Heat, light, and oxygen can accelerate oxidation. For final packaging, quality producers commonly use dark glass bottles or tins to help reduce exposure to light.

Storage remains important after the oil leaves the mill. For the complete explanation, see our guide to how to store olive oil.

How Is Extra Virgin Olive Oil Made?

Extra virgin olive oil is made directly from olives using mechanical or physical extraction methods and must also meet the chemical and sensory requirements for the extra virgin grade.

It follows the same fundamental process described above: harvesting, cleaning, crushing, malaxation, separation, clarification, storage, and bottling.

However, mechanical extraction alone does not automatically make an olive oil extra virgin.

The finished oil must also meet the applicable requirements for the grade. In the United States, extra virgin olive oil must have no sensory defects, show positive fruitiness, and have free fatty acids of no more than 0.8 grams per 100 grams.

Production makes the oil. Classification determines the grade.

An olive oil may be mechanically extracted but fail to qualify as extra virgin if it has sensory defects or does not meet the required chemical standards.

Is Extra Virgin Olive Oil Refined?

No. Extra virgin olive oil is not refined.

Extra virgin olive oil belongs to the virgin olive-oil category. It is obtained directly from olives through mechanical or physical processes rather than through refining.

Refining is used for oils that do not qualify as virgin olive oil for direct consumption. During refining, producers may use processes that reduce undesirable flavors, odors, acidity, or color. The resulting product is refined olive oil—not extra virgin olive oil.

This is why olive oil and extra virgin olive oil are not always interchangeable terms on a label. A product simply labeled “olive oil” may contain refined olive oil blended with virgin olive oil.

Is Olive Oil Cold Pressed or Cold Extracted?

Cold pressed and cold extracted describe extraction methods, while extra virgin describes an olive-oil quality grade.

Cold pressed olive oil traditionally refers to oil separated from olive paste using a mechanical press under controlled temperature conditions.

Cold extracted olive oil generally refers to oil extracted using a modern mechanical system, often centrifugation, at controlled low temperatures. The phrase is commonly associated with extraction below 27°C, or 80.6°F, although extra virgin status itself depends on more than extraction temperature.

A bottle can be extra virgin without featuring a “cold extracted” claim, provided it meets the applicable requirements for the grade. Likewise, a low-temperature extraction claim alone does not guarantee that an oil qualifies as extra virgin.

For the complete distinction, see our guide to cold pressed vs. cold extracted olive oil.

Why Do Olive Oils Taste Different?

Olive oils taste different because cultivar, growing conditions, harvest timing, olive ripeness, milling decisions, filtration, storage, and freshness can all influence the finished oil.

Important variables include:

• Olive cultivar or variety
• Growing region and climate
• Soil and rainfall conditions
• Harvest timing and olive ripeness
• Time between harvest and milling
• Milling, malaxation, and separation practices
• Filtration and storage decisions
• Packaging and freshness at the time of purchase

A fresh extra virgin olive oil may taste grassy, herbaceous, peppery, bitter, buttery, fruity, floral, nutty, tomato-like, or almond-like.

Bitterness and throat-catching pungency can be natural sensory attributes of fresh extra virgin olive oil, particularly oils made from greener olives.

For the complete explanation of bitterness, pepperiness, pungency, freshness, and sensory interpretation, see our guide to why olive oil tastes peppery or bitter.

Continue Learning About Olive Oil

Production is only one part of understanding olive oil. Continue with our guides to classification, cold extraction, acidity, polyphenols, storage, and how to evaluate olive oil labels.

• What Is Extra Virgin Olive Oil?
• How Italian Olive Oil Is Classified
• Cold Pressed vs. Cold Extracted Olive Oil
• How to Store Olive Oil

How Is Olive Oil Made? The Bottom Line

Olive oil is made by harvesting olives, cleaning them, crushing them into paste, mixing the paste through malaxation, separating the oil from water and olive solids, clarifying the oil, and then storing and bottling it.

Harvest → Clean → Crush → Malax → Separate → Clarify → Store → Bottle

Extra virgin olive oil uses this mechanical or physical production pathway but must additionally satisfy the chemical and sensory requirements of the extra virgin grade.

Production makes the oil. Classification determines the grade.