The lowdown on choosing, using and enjoying good olive oil.
Choosing an olive oil can feel complicated. There’s so much to think about: acidity, polyphenols, harvest dates, dark bottles, early harvesting and cold extraction. Then you have people who say you should never cook with extra virgin olive oil, while others use it for almost everything. There are gold medals, pictures of ancient olive trees and words such as premium, reserve and first press bandied about—but what do they actually mean?
Yes, there’s a lot to learn, but actually most of it is pretty simple and once you get your head around a few basic principles it gets a lot easier.
I started Sarah & Olive because I loved olive oil and knew that it was tricky to track down the good stuff.I also wanted customers to better understand what they were buying, how they would use it and why some olive oils taste so much better than others.
The first thing I had to do was learn all this myself, so over the years I’ve done tasting courses, become an olive oil sommelier, visited farms and mills, had countless conversations with producers and other people in the business and always had a slightly unreasonable number of open bottles in my kitchen.
This is the guide I wish I had when I started.
It explains what extra virgin olive oil actually is, what matters when you buy it, how to taste and use it and why knowing about variety, freshness and the people making it is far more helpful than most of the language printed on the label.
If you remember one thing
A good extra virgin olive oil should smell fresh and taste alive.
The most important thing to know about extra virgin olive oil
That applies whether the oil is light and delicate, complex and herbaceous or robust and peppery. When you smell it, there should be something recognisably fresh there—perhaps grass, green almond, tomato leaf, herbs, apple or softer ripe fruit.
If an oil smells waxy, like old nuts or crayons, it is probably rancid. An oil that smells of almost nothing may be old, poorly stored or simply made in a flatter style, but it won’t give you the fresh, lively character I look for.
A fresh oil may also have some bitterness on the tongue or a peppery catch at the back of the throat. These are positive characteristics and are often associated with the naturally occurring phenolic compounds in the oil.
That freshness is what lifts a bowl of beans, a tomato, a piece of bread or a plate of pasta and makes the simplest food taste as though considerably more has happened to it.
What is extra virgin olive oil?
At its simplest, extra virgin olive oil is the oil extracted from fresh olives using only mechanical processes, without the chemical refining used to correct lower-grade oils.
“Mechanical” refers to the crushing, mixing and separation of the oil—not necessarily to how the olives are picked. Olives may be harvested by hand or with carefully managed machinery.
What really matters is that the fruit remains in good condition and reaches the mill quickly.
These days, the best olive oil is made fast. Olives are harvested efficiently and not left sitting around in the sun where they will start to deteriorate. They are taken to the mill as quickly as possible and processed at carefully controlled temperatures, with exposure to oxygen kept to a minimum.
In a nutshell, extra virgin olive oil is fresh olive juice that has been handled well from the grove to the bottle.
That sounds simple, but olives are exceptionally unforgiving.
Once picked, they begin to deteriorate. If they are bruised, left sitting in warm heaps or fail to reach the mill quickly, the quality of the resulting oil suffers. A producer can grow wonderful olives for an entire year and lose much of that work during the hours between harvesting and milling.
The best producers are obsessed with these details. Olives are picked carefully—and quickly—transported in ventilated crates or trailers and milled as fast as possible, often within a few hours.
Meet the maker: If you want to see what this looks like in practice, read about my visit to Finca la Torre and Víctor Pérez Serrano’s pursuit of exceptional olive oil.
What is the difference between extra virgin, virgin and ordinary olive oil?
This is one of the more confusing parts of buying olive oil because the bottles can look very similar.
Extra virgin olive oil
Extra virgin olive oil is produced mechanically and must meet the highest chemical and sensory grade.
Among the requirements, it must have free acidity of no more than 0.8%, expressed as oleic acid. This is one indication of the condition of the fruit and how it was handled before and during production, but it is not a complete measure of quality.
And importantly, extra virgin status is not decided by chemistry alone.
The oil also undergoes sensory assessment by a trained tasting panel. It must show fruitiness and be free from the sensory defects that would place it in a lower category.
An oil can perform well in chemical tests but still taste stale, musty, fermented or otherwise faulty.
Virgin olive oil
Virgin olive oil is also produced mechanically, but it may have free acidity of up to 2% and/or sensory defects that prevent it from qualifying as extra virgin.
Olive oil
A bottle labelled simply “olive oil” is a different product.
It generally contains olive oil that has undergone refining to remove defects, blended with some virgin or extra virgin olive oil to add flavour and colour.
Refining produces a much more neutral oil and removes much of the aroma, flavour and character that make a good extra virgin olive oil so interesting.
GOOD TO KNOW: “Pure olive oil” sounds impressive, but it is not a higher grade than extra virgin. It generally refers to refined olive oil blended with some virgin olive oil.
Olive oil is a fruit juice
This is probably the most useful way to think about it.
Olives are fruit, and extra virgin olive oil is their juice.
Like other fresh foods, olive oil is at its best when it is fresh and, because a good extra virgin olive oil has not been refined, it needs to be protected and looked after properly.
For a long time, we tended to think about olive oil in much the same way as other cooking oils. I think this is a mistake.
A good extra virgin olive oil has much more in common with fresh produce.
It has a harvest season, an olive variety and a place of origin. Its flavours change according to the ripeness of the fruit, the weather, farming practices and the decisions made during milling.
And unlike a neutral refined oil that can sit forgotten at the back of the cupboard, a good extra virgin olive oil is something to use while it is still fresh.
As a general buying rule, I look for oil from the most recent harvest and aim to use it while it still has all that wonderful freshness and character.
Once you start thinking of olive oil as fruit juice, several things make much more sense:
- Freshness matters.
- Light, heat and air damage it.
- Different olive varieties taste different.
- Knowing the harvest date is very useful. Always try to buy the most recent harvest.
- An open bottle is meant to be used, not admired indefinitely.
It also explains why good oils can smell of things that were never added to them: tomato leaf, freshly cut grass, green almond, apple, herbs, artichoke, banana or olive leaf.
These are natural aromas created by the fruit and the production process.
There isn’t any tomato or grass in the bottle, in the same way that a wine described as tasting of blackberry does not contain a handful of actual blackberries.
Why fresh olive oil tastes different
The first thing I notice when a really fresh oil is poured is the smell.
It might be grassy and intensely green or softer and fruitier, but it smells alive.
An old or tired oil tends to smell flat, vaguely waxy or like very little at all.
Freshness in olive oil is not simply about whether the bottle has passed its best-before date. That date is usually calculated from bottling rather than harvesting, which is why I always look for a harvest year where possible.
In the Northern Hemisphere, olives are generally harvested during the autumn and winter, with premium early-harvest oils usually produced during the earlier part of the season.
Once a bottle is opened, the oil is exposed to oxygen every time you use it.
This is why I would much rather see someone finish a good bottle generously over a couple of months than ration it by the teaspoon for a year.
I've written more about making good olive oil part of everyday eating in What happens when you eat extra virgin olive oil every day?
Does olive oil improve with age?
No.
Even exceptionally well-made oil gradually loses aroma, flavour and antioxidants over time.
A robust, high-polyphenol oil may retain its character for longer than a very delicate one, but neither improves by sitting in a cupboard.
Olive oil is not wine. Fresh is better.
What does “early harvest” mean?
An olive changes considerably as it ripens.
Early in the season, the fruit is green, firm and relatively low in oil. As it ripens, it becomes softer and darker and contains considerably more oil.
Early-harvest olive oil is made from olives picked while they are still green or just beginning to change colour.
This has an important consequence: you need considerably more olives to make a litre of oil.
Depending on the variety, season and ripeness, a litre of very early-harvest oil may require around 8–11kg of olives, while riper fruit can sometimes produce a litre from roughly 4–6kg.
The exact figures vary, but the principle is simple: early fruit produces considerably less oil.
The producer is sacrificing yield in return for freshness, intensity, aroma and, often, higher levels of phenolic compounds.
This is one of the reasons really good early-harvest olive oil costs more.
The flavour is often greener and more assertive, with notes such as tomato leaf, artichoke, herbs and green almond. There may also be bitterness and a peppery finish.
Later-harvest oils can be softer, sweeter and riper in style. They are not automatically poor quality. Ripeness is one of many choices a skilled producer makes, and a gentler oil can be exactly what you want with fish, baking, mayonnaise or delicate vegetables.
I generally prefer early-harvest oils because I love that vivid green character, but the best oil is the one that suits the food and the person eating it.
Taste what I mean
Finca la Torre Hojiblanca
This is a lovely example of the vivid green character I mean when I talk about early-harvest olive oil. Made from early-harvest Hojiblanca olives on Finca la Torre's organic and biodynamic estate in Andalucía, it has notes of cut grass, citrus peel and green almond with a gentle peppery finish.
Bitterness and pepperiness are usually good signs
People are often surprised when an olive oil tastes bitter at the front of the mouth or catches slightly at the back of the throat.
This is especially common if they are used to mild supermarket oils.
Bitterness and pungency are recognised positive sensory attributes in extra virgin olive oil. They are often associated with fresh green fruit and phenolic compounds, although their intensity varies enormously according to olive variety, ripeness and production style.
A robust Picual or Coratina may be distinctly bitter and peppery.
A softer Arbequina can be fragrant, fruity and almost sweet.
Both may be excellent.
The important distinction is between pleasant bitterness and a defect.
Good bitterness feels fresh and food-like: think radicchio, rocket, artichoke or green almond skin.
A rancid oil tastes tired and stale and can remind you of old nuts, wax crayons or putty.
And pepperiness is not a measure of acidity.
You cannot taste free acidity in olive oil. That sharp tickle in your throat is a sensory characteristic, not the oil “burning” because it is acidic.
SARAH'S TIP: Taste a spoonful of oil on its own as well as with a piece of bread. Bread is very good at hiding both defects and subtler flavours.
What are polyphenols?
Polyphenols are naturally occurring compounds found in olives and olive oil. They contribute to bitterness, pungency, antioxidant activity and the oil’s stability.
You will often see a total polyphenol figure expressed in milligrams per kilogram (mg/kg).
A higher number can indicate a more robust and potentially more stable oil, but it is not the only measure of quality. Laboratory methods can also differ, so figures are not always directly comparable.
Olive variety makes a significant difference.
Picual and Coratina, for example, are often naturally high in polyphenols, while Arbequina tends to produce a gentler style. Harvest timing, irrigation, climate, milling and storage also affect the final result.
There is an authorised EU health claim relating to olive oil polyphenols and the protection of blood lipids from oxidative stress. The claim can only be used when an oil contains the required amount of hydroxytyrosol and its derivatives, and it must be accompanied by information about the daily intake required to obtain the beneficial effect.
You will sometimes see this simplified to a figure of 250mg/kg, but laboratory methods and the compounds being measured can differ, so I always rely on the producer’s current analysis rather than treating one headline number as the whole story.
Many of the oils I select for Sarah & Olive are naturally very high in polyphenols, with some recording considerably higher figures.
But I don't think everyone needs to chase the highest number they can find.
If you love powerful, bitter and peppery oils, or are particularly interested in phenolic content, look for an oil with a recent analysis from the producer.
If you prefer a softer, more delicate oil, the bottle with the highest polyphenol figure may simply not be the oil you enjoy most.
For a much deeper explanation, read Why is everyone talking about polyphenols?
If high polyphenols are what you're looking for
You can explore my high-polyphenol extra virgin olive oil collection, which brings together the robust, early-harvest oils I currently stock.
One particularly useful oil for understanding the relationship between variety, bitterness, pungency and polyphenols is Coratina. I wrote about this unusual Spanish-grown Coratina after tasting it at an olive oil masterclass in Italy.
Acidity: important, but widely misunderstood
Free acidity is one of the chemical measures used to classify olive oil.
It refers to the percentage of free fatty acids, expressed as oleic acid. For an oil to qualify as extra virgin, free acidity must be no more than 0.8%.
Very high-quality oils often have substantially lower figures.
But lower acidity does not automatically mean better flavour.
It tells us something about the condition of the olives and how they were handled before and during production, but it does not provide a complete quality score.
And this is worth repeating:
You cannot taste free acidity.
An oil that tastes intensely peppery does not therefore have “high acidity”, and a very mild oil is not necessarily low in acidity.
“Cold pressed” and “first press”
These are two of the most successful phrases in olive oil marketing, partly because they sound reassuringly traditional.
The problem is that, for most modern premium olive oils, “first cold pressed” doesn't really make sense anymore.
Historically, olive paste was spread onto fibre mats and physically pressed. The first pressing produced the best liquid, while further pressing using additional heat or water extracted more.
Most high-quality modern extra virgin olive oil isn't produced that way.
Today, the olives are crushed into a paste, gently mixed and the oil separated using a centrifuge.
There is no first press because there is no press.
The term cold extraction is more relevant. Under EU labelling rules, it refers to oil obtained below 27°C using modern extraction methods.
Temperature matters because excessive heat can increase the amount of oil extracted while compromising some of its aromas and quality.
However, virtually every serious premium producer controls temperature carefully, so the words cold extracted alone don't tell me that an oil is exceptional.
I would put much more weight on:
- a clear harvest year;
- a named producer or estate;
- a specific olive variety;
- transparent origin;
- good storage and packaging;
- and, ultimately, how the oil smells and tastes.
If you're curious about why those production choices make premium oils more expensive, I've written about that too: explore more of my olive oil guides and stories.
Does colour tell you whether olive oil is good?
Not reliably.
Olive oil can range from vivid emerald green to pale gold depending on the olive variety, ripeness, natural pigments and production.
And while we all love how a brilliantly green oil looks on a plate, colour alone does not prove freshness or quality.
Equally, a golden oil is not necessarily old, poor quality or refined.
Professional olive oil tasters use dark blue or amber tasting glasses so that the colour of the oil does not influence their assessment.
At home, enjoy the colour.
Just don't use it as your quality test.
Your nose and your palate will tell you much more.
Want to put some of this into practice?
You don't need the most expensive olive oil on the shelf and you certainly don't need to buy every oil I sell. The useful thing is to work out how you actually use olive oil.
For everyday cooking
If you roast vegetables, cook fish, make dressings, bake or generally use olive oil with abandon, start with an oil you can afford to pour generously.
For tasting and finishing
If you're looking for the oils where variety, producer, harvest and complexity really come into their own, this is where I would start.
For high polyphenols
If you particularly enjoy robust, green, bitter and peppery oils—or want to explore oils with current producer analysis—I've brought them together here.
Explore High-Polyphenol Olive Oils →
Or let me choose for you
The Sarah & Olive Tasting Club is probably the nicest way to learn the differences for yourself. I choose a different premium Spanish extra virgin olive oil for each delivery, with tasting notes, information about the producer and ideas for using it.
Keep learning about olive oil
If you'd like to go a little further down the olive-oil rabbit hole, these are good places to continue:
About the author
Sarah Merrigan is the founder of Sarah & Olive and an olive oil sommelier. She works directly with Spanish producers, visits farms and mills and tastes each new harvest to choose the oils sold by Sarah & Olive.
Choosing an olive oil can feel complicated. There’s so much to think about: acidity, polyphenols, harvest dates, dark bottles, early harvesting and cold extraction. Then you have people who say you should never cook with extra virgin olive oil, while others use it for almost everything. There are gold medals, pictures of ancient olive trees and words such as premium, reserve and first press bandied about—but what do they actually mean?
Yes, there’s a lot to learn, but actually most of it is pretty simple and once you get your head around a few basic principles it gets a lot easier.
I started Sarah & Olive because I loved olive oil and knew that it was tricky to track down the good stuff. I also wanted customers to better understand what they were buying, how they would use it and why some olive oils taste so much better than others.
The first thing I had to do was learn all this myself, so over the years I’ve done tasting courses, become an olive oil sommelier, visited farms and mills, had countless conversations with producers and other people in the business and always had a slightly unreasonable number of open bottles in my kitchen.
This is the guide I wish I had when I started.
It explains what extra virgin olive oil actually is, what matters when you buy it, how to taste and use it and why knowing about variety, freshness and the people making it is far more helpful than most of the language printed on the label.
If you remember one thing
A good extra virgin olive oil should smell fresh and taste alive.
The most important thing to know about extra virgin olive oil
That applies whether the oil is light and delicate, complex and herbaceous or robust and peppery. When you smell it, there should be something recognisably fresh there—perhaps grass, green almond, tomato leaf, herbs, apple or softer ripe fruit.
If an oil smells waxy, like old nuts or crayons, it is probably rancid. An oil that smells of almost nothing may be old, poorly stored or simply made in a flatter style, but it won’t give you the fresh, lively character I look for.
A fresh oil may also have some bitterness on the tongue or a peppery catch at the back of the throat. These are positive characteristics and are often associated with the naturally occurring phenolic compounds in the oil.
That freshness is what lifts a bowl of beans, a tomato, a piece of bread or a plate of pasta and makes the simplest food taste as though considerably more has happened to it.
What is extra virgin olive oil?
At its simplest, extra virgin olive oil is the oil extracted from fresh olives using only mechanical processes, without the chemical refining used to correct lower-grade oils.
“Mechanical” refers to the crushing, mixing and separation of the oil—not necessarily to how the olives are picked. Olives may be harvested by hand or with carefully managed machinery.
What really matters is that the fruit remains in good condition and reaches the mill quickly.
These days, the best olive oil is made fast. Olives are harvested efficiently and not left sitting around in the sun where they will start to deteriorate. They are taken to the mill as quickly as possible and processed at carefully controlled temperatures, with exposure to oxygen kept to a minimum.
In a nutshell, extra virgin olive oil is fresh olive juice that has been handled well from the grove to the bottle.
That sounds simple, but olives are exceptionally unforgiving.
Once picked, they begin to deteriorate. If they are bruised, left sitting in warm heaps or fail to reach the mill quickly, the quality of the resulting oil suffers. A producer can grow wonderful olives for an entire year and lose much of that work during the hours between harvesting and milling.
The best producers are obsessed with these details. Olives are picked carefully—and quickly—transported in ventilated crates or trailers and milled as fast as possible, often within a few hours.
Meet the maker: If you want to see what this looks like in practice, read about my visit to Finca la Torre and Víctor Pérez Serrano’s pursuit of exceptional olive oil.
What is the difference between extra virgin, virgin and ordinary olive oil?
This is one of the more confusing parts of buying olive oil because the bottles can look very similar.
Extra virgin olive oil
Extra virgin olive oil is produced mechanically and must meet the highest chemical and sensory grade.
Among the requirements, it must have free acidity of no more than 0.8%, expressed as oleic acid. This is one indication of the condition of the fruit and how it was handled before and during production, but it is not a complete measure of quality.
And importantly, extra virgin status is not decided by chemistry alone.
The oil also undergoes sensory assessment by a trained tasting panel. It must show fruitiness and be free from the sensory defects that would place it in a lower category.
An oil can perform well in chemical tests but still taste stale, musty, fermented or otherwise faulty.
Virgin olive oil
Virgin olive oil is also produced mechanically, but it may have free acidity of up to 2% and/or sensory defects that prevent it from qualifying as extra virgin.
Olive oil
A bottle labelled simply “olive oil” is a different product.
It generally contains olive oil that has undergone refining to remove defects, blended with some virgin or extra virgin olive oil to add flavour and colour.
Refining produces a much more neutral oil and removes much of the aroma, flavour and character that make a good extra virgin olive oil so interesting.
GOOD TO KNOW: “Pure olive oil” sounds impressive, but it is not a higher grade than extra virgin. It generally refers to refined olive oil blended with some virgin olive oil.
Olive oil is a fruit juice
This is probably the most useful way to think about it.
Olives are fruit, and extra virgin olive oil is their juice.
Like other fresh foods, olive oil is at its best when it is fresh and, because a good extra virgin olive oil has not been refined, it needs to be protected and looked after properly.
For a long time, we tended to think about olive oil in much the same way as other cooking oils. I think this is a mistake.
A good extra virgin olive oil has much more in common with fresh produce.
It has a harvest season, an olive variety and a place of origin. Its flavours change according to the ripeness of the fruit, the weather, farming practices and the decisions made during milling.
And unlike a neutral refined oil that can sit forgotten at the back of the cupboard, a good extra virgin olive oil is something to use while it is still fresh.
As a general buying rule, I look for oil from the most recent harvest and aim to use it while it still has all that wonderful freshness and character.
Once you start thinking of olive oil as fruit juice, several things make much more sense:
- Freshness matters.
- Light, heat and air damage it.
- Different olive varieties taste different.
- Knowing the harvest date is very useful. Always try to buy the most recent harvest.
- An open bottle is meant to be used, not admired indefinitely.
It also explains why good oils can smell of things that were never added to them: tomato leaf, freshly cut grass, green almond, apple, herbs, artichoke, banana or olive leaf.
These are natural aromas created by the fruit and the production process.
There isn’t any tomato or grass in the bottle, in the same way that a wine described as tasting of blackberry does not contain a handful of actual blackberries.
Why fresh olive oil tastes different
The first thing I notice when a really fresh oil is poured is the smell.
It might be grassy and intensely green or softer and fruitier, but it smells alive.
An old or tired oil tends to smell flat, vaguely waxy or like very little at all.
Freshness in olive oil is not simply about whether the bottle has passed its best-before date. That date is usually calculated from bottling rather than harvesting, which is why I always look for a harvest year where possible.
In the Northern Hemisphere, olives are generally harvested during the autumn and winter, with premium early-harvest oils usually produced during the earlier part of the season.
Once a bottle is opened, the oil is exposed to oxygen every time you use it.
This is why I would much rather see someone finish a good bottle generously over a couple of months than ration it by the teaspoon for a year.
I've written more about making good olive oil part of everyday eating in What happens when you eat extra virgin olive oil every day?
Does olive oil improve with age?
No.
Even exceptionally well-made oil gradually loses aroma, flavour and antioxidants over time.
A robust, high-polyphenol oil may retain its character for longer than a very delicate one, but neither improves by sitting in a cupboard.
Olive oil is not wine. Fresh is better.
What does “early harvest” mean?
An olive changes considerably as it ripens.
Early in the season, the fruit is green, firm and relatively low in oil. As it ripens, it becomes softer and darker and contains considerably more oil.
Early-harvest olive oil is made from olives picked while they are still green or just beginning to change colour.
This has an important consequence: you need considerably more olives to make a litre of oil.
Depending on the variety, season and ripeness, a litre of very early-harvest oil may require around 8–11kg of olives, while riper fruit can sometimes produce a litre from roughly 4–6kg.
The exact figures vary, but the principle is simple: early fruit produces considerably less oil.
The producer is sacrificing yield in return for freshness, intensity, aroma and, often, higher levels of phenolic compounds.
This is one of the reasons really good early-harvest olive oil costs more.
The flavour is often greener and more assertive, with notes such as tomato leaf, artichoke, herbs and green almond. There may also be bitterness and a peppery finish.
Later-harvest oils can be softer, sweeter and riper in style. They are not automatically poor quality. Ripeness is one of many choices a skilled producer makes, and a gentler oil can be exactly what you want with fish, baking, mayonnaise or delicate vegetables.
I generally prefer early-harvest oils because I love that vivid green character, but the best oil is the one that suits the food and the person eating it.
Taste what I mean
Finca la Torre Hojiblanca
This is a lovely example of the vivid green character I mean when I talk about early-harvest olive oil. Made from early-harvest Hojiblanca olives on Finca la Torre's organic and biodynamic estate in Andalucía, it has notes of cut grass, citrus peel and green almond with a gentle peppery finish.
Bitterness and pepperiness are usually good signs
People are often surprised when an olive oil tastes bitter at the front of the mouth or catches slightly at the back of the throat.
This is especially common if they are used to mild supermarket oils.
Bitterness and pungency are recognised positive sensory attributes in extra virgin olive oil. They are often associated with fresh green fruit and phenolic compounds, although their intensity varies enormously according to olive variety, ripeness and production style.
A robust Picual or Coratina may be distinctly bitter and peppery.
A softer Arbequina can be fragrant, fruity and almost sweet.
Both may be excellent.
The important distinction is between pleasant bitterness and a defect.
Good bitterness feels fresh and food-like: think radicchio, rocket, artichoke or green almond skin.
A rancid oil tastes tired and stale and can remind you of old nuts, wax crayons or putty.
And pepperiness is not a measure of acidity.
You cannot taste free acidity in olive oil. That sharp tickle in your throat is a sensory characteristic, not the oil “burning” because it is acidic.
SARAH'S TIP: Taste a spoonful of oil on its own as well as with a piece of bread. Bread is very good at hiding both defects and subtler flavours.
What are polyphenols?
Polyphenols are naturally occurring compounds found in olives and olive oil. They contribute to bitterness, pungency, antioxidant activity and the oil’s stability.
You will often see a total polyphenol figure expressed in milligrams per kilogram (mg/kg).
A higher number can indicate a more robust and potentially more stable oil, but it is not the only measure of quality. Laboratory methods can also differ, so figures are not always directly comparable.
Olive variety makes a significant difference.
Picual and Coratina, for example, are often naturally high in polyphenols, while Arbequina tends to produce a gentler style. Harvest timing, irrigation, climate, milling and storage also affect the final result.
There is an authorised EU health claim relating to olive oil polyphenols and the protection of blood lipids from oxidative stress. The claim can only be used when an oil contains the required amount of hydroxytyrosol and its derivatives, and it must be accompanied by information about the daily intake required to obtain the beneficial effect.
You will sometimes see this simplified to a figure of 250mg/kg, but laboratory methods and the compounds being measured can differ, so I always rely on the producer’s current analysis rather than treating one headline number as the whole story.
Many of the oils I select for Sarah & Olive are naturally very high in polyphenols, with some recording considerably higher figures.
But I don't think everyone needs to chase the highest number they can find.
If you love powerful, bitter and peppery oils, or are particularly interested in phenolic content, look for an oil with a recent analysis from the producer.
If you prefer a softer, more delicate oil, the bottle with the highest polyphenol figure may simply not be the oil you enjoy most.
For a much deeper explanation, read Why is everyone talking about polyphenols?
If high polyphenols are what you're looking for
You can explore my high-polyphenol extra virgin olive oil collection, which brings together the robust, early-harvest oils I currently stock.
One particularly useful oil for understanding the relationship between variety, bitterness, pungency and polyphenols is Coratina. I wrote about this unusual Spanish-grown Coratina after tasting it at an olive oil masterclass in Italy.
Acidity: important, but widely misunderstood
Free acidity is one of the chemical measures used to classify olive oil.
It refers to the percentage of free fatty acids, expressed as oleic acid. For an oil to qualify as extra virgin, free acidity must be no more than 0.8%.
Very high-quality oils often have substantially lower figures.
But lower acidity does not automatically mean better flavour.
It tells us something about the condition of the olives and how they were handled before and during production, but it does not provide a complete quality score.
And this is worth repeating:
You cannot taste free acidity.
An oil that tastes intensely peppery does not therefore have “high acidity”, and a very mild oil is not necessarily low in acidity.
“Cold pressed” and “first press”
These are two of the most successful phrases in olive oil marketing, partly because they sound reassuringly traditional.
The problem is that, for most modern premium olive oils, “first cold pressed” doesn't really make sense anymore.
Historically, olive paste was spread onto fibre mats and physically pressed. The first pressing produced the best liquid, while further pressing using additional heat or water extracted more.
Most high-quality modern extra virgin olive oil isn't produced that way.
Today, the olives are crushed into a paste, gently mixed and the oil separated using a centrifuge.
There is no first press because there is no press.
The term cold extraction is more relevant. Under EU labelling rules, it refers to oil obtained below 27°C using modern extraction methods.
Temperature matters because excessive heat can increase the amount of oil extracted while compromising some of its aromas and quality.
However, virtually every serious premium producer controls temperature carefully, so the words cold extracted alone don't tell me that an oil is exceptional.
I would put much more weight on:
- a clear harvest year;
- a named producer or estate;
- a specific olive variety;
- transparent origin;
- good storage and packaging;
- and, ultimately, how the oil smells and tastes.
If you're curious about why those production choices make premium oils more expensive, I've written about that too: explore more of my olive oil guides and stories.
Does colour tell you whether olive oil is good?
Not reliably.
Olive oil can range from vivid emerald green to pale gold depending on the olive variety, ripeness, natural pigments and production.
And while we all love how a brilliantly green oil looks on a plate, colour alone does not prove freshness or quality.
Equally, a golden oil is not necessarily old, poor quality or refined.
Professional olive oil tasters use dark blue or amber tasting glasses so that the colour of the oil does not influence their assessment.
At home, enjoy the colour.
Just don't use it as your quality test.
Your nose and your palate will tell you much more.
Want to put some of this into practice?
You don't need the most expensive olive oil on the shelf and you certainly don't need to buy every oil I sell. The useful thing is to work out how you actually use olive oil.
For everyday cooking
If you roast vegetables, cook fish, make dressings, bake or generally use olive oil with abandon, start with an oil you can afford to pour generously.
For tasting and finishing
If you're looking for the oils where variety, producer, harvest and complexity really come into their own, this is where I would start.
For high polyphenols
If you particularly enjoy robust, green, bitter and peppery oils—or want to explore oils with current producer analysis—I've brought them together here.
Explore High-Polyphenol Olive Oils →
Or let me choose for you
The Sarah & Olive Tasting Club is probably the nicest way to learn the differences for yourself. I choose a different premium Spanish extra virgin olive oil for each delivery, with tasting notes, information about the producer and ideas for using it.
Keep learning about olive oil
If you'd like to go a little further down the olive-oil rabbit hole, these are good places to continue:
About the author
Sarah Merrigan is the founder of Sarah & Olive and an olive oil sommelier. She works directly with Spanish producers, visits farms and mills and tastes each new harvest to choose the oils sold by Sarah & Olive.
Choosing an olive oil can feel complicated. There’s so much to think about: acidity, polyphenols, harvest dates, dark bottles, early harvesting and cold extraction. Then you have people who say you should never cook with extra virgin olive oil, while others use it for almost everything. There are gold medals, pictures of ancient olive trees and words such as premium, reserve and first press bandied about—but what do they actually mean?
Yes, there’s a lot to learn, but actually most of it is pretty simple and once you get your head around a few basic principles it gets a lot easier.
I started Sarah & Olive because I loved olive oil and knew that it was tricky to track down the good stuff. I also wanted customers to better understand what they were buying, how they would use it and why some olive oils taste so much better than others.
The first thing I had to do was learn all this myself, so over the years I’ve done tasting courses, become an olive oil sommelier, visited farms and mills, had countless conversations with producers and other people in the business and always had a slightly unreasonable number of open bottles in my kitchen.
This is the guide I wish I had when I started.
It explains what extra virgin olive oil actually is, what matters when you buy it, how to taste and use it and why knowing about variety, freshness and the people making it is far more helpful than most of the language printed on the label.
If you remember one thing
A good extra virgin olive oil should smell fresh and taste alive.
The most important thing to know about extra virgin olive oil
That applies whether the oil is light and delicate, complex and herbaceous or robust and peppery. When you smell it, there should be something recognisably fresh there—perhaps grass, green almond, tomato leaf, herbs, apple or softer ripe fruit.
If an oil smells waxy, like old nuts or crayons, it is probably rancid. An oil that smells of almost nothing may be old, poorly stored or simply made in a flatter style, but it won’t give you the fresh, lively character I look for.
A fresh oil may also have some bitterness on the tongue or a peppery catch at the back of the throat. These are positive characteristics and are often associated with the naturally occurring phenolic compounds in the oil.
That freshness is what lifts a bowl of beans, a tomato, a piece of bread or a plate of pasta and makes the simplest food taste as though considerably more has happened to it.
What is extra virgin olive oil?
At its simplest, extra virgin olive oil is the oil extracted from fresh olives using only mechanical processes, without the chemical refining used to correct lower-grade oils.
“Mechanical” refers to the crushing, mixing and separation of the oil—not necessarily to how the olives are picked. Olives may be harvested by hand or with carefully managed machinery.
What really matters is that the fruit remains in good condition and reaches the mill quickly.
These days, the best olive oil is made fast. Olives are harvested efficiently and not left sitting around in the sun where they will start to deteriorate. They are taken to the mill as quickly as possible and processed at carefully controlled temperatures, with exposure to oxygen kept to a minimum.
In a nutshell, extra virgin olive oil is fresh olive juice that has been handled well from the grove to the bottle.
That sounds simple, but olives are exceptionally unforgiving.
Once picked, they begin to deteriorate. If they are bruised, left sitting in warm heaps or fail to reach the mill quickly, the quality of the resulting oil suffers. A producer can grow wonderful olives for an entire year and lose much of that work during the hours between harvesting and milling.
The best producers are obsessed with these details. Olives are picked carefully—and quickly—transported in ventilated crates or trailers and milled as fast as possible, often within a few hours.
Meet the maker: If you want to see what this looks like in practice, read about my visit to Finca la Torre and Víctor Pérez Serrano’s pursuit of exceptional olive oil.
What is the difference between extra virgin, virgin and ordinary olive oil?
This is one of the more confusing parts of buying olive oil because the bottles can look very similar.
Extra virgin olive oil
Extra virgin olive oil is produced mechanically and must meet the highest chemical and sensory grade.
Among the requirements, it must have free acidity of no more than 0.8%, expressed as oleic acid. This is one indication of the condition of the fruit and how it was handled before and during production, but it is not a complete measure of quality.
And importantly, extra virgin status is not decided by chemistry alone.
The oil also undergoes sensory assessment by a trained tasting panel. It must show fruitiness and be free from the sensory defects that would place it in a lower category.
An oil can perform well in chemical tests but still taste stale, musty, fermented or otherwise faulty.
Virgin olive oil
Virgin olive oil is also produced mechanically, but it may have free acidity of up to 2% and/or sensory defects that prevent it from qualifying as extra virgin.
Olive oil
A bottle labelled simply “olive oil” is a different product.
It generally contains olive oil that has undergone refining to remove defects, blended with some virgin or extra virgin olive oil to add flavour and colour.
Refining produces a much more neutral oil and removes much of the aroma, flavour and character that make a good extra virgin olive oil so interesting.
GOOD TO KNOW: “Pure olive oil” sounds impressive, but it is not a higher grade than extra virgin. It generally refers to refined olive oil blended with some virgin olive oil.
Olive oil is a fruit juice
This is probably the most useful way to think about it.
Olives are fruit, and extra virgin olive oil is their juice.
Like other fresh foods, olive oil is at its best when it is fresh and, because a good extra virgin olive oil has not been refined, it needs to be protected and looked after properly.
For a long time, we tended to think about olive oil in much the same way as other cooking oils. I think this is a mistake.
A good extra virgin olive oil has much more in common with fresh produce.
It has a harvest season, an olive variety and a place of origin. Its flavours change according to the ripeness of the fruit, the weather, farming practices and the decisions made during milling.
And unlike a neutral refined oil that can sit forgotten at the back of the cupboard, a good extra virgin olive oil is something to use while it is still fresh.
As a general buying rule, I look for oil from the most recent harvest and aim to use it while it still has all that wonderful freshness and character.
Once you start thinking of olive oil as fruit juice, several things make much more sense:
- Freshness matters.
- Light, heat and air damage it.
- Different olive varieties taste different.
- Knowing the harvest date is very useful. Always try to buy the most recent harvest.
- An open bottle is meant to be used, not admired indefinitely.
It also explains why good oils can smell of things that were never added to them: tomato leaf, freshly cut grass, green almond, apple, herbs, artichoke, banana or olive leaf.
These are natural aromas created by the fruit and the production process.
There isn’t any tomato or grass in the bottle, in the same way that a wine described as tasting of blackberry does not contain a handful of actual blackberries.
Why fresh olive oil tastes different
The first thing I notice when a really fresh oil is poured is the smell.
It might be grassy and intensely green or softer and fruitier, but it smells alive.
An old or tired oil tends to smell flat, vaguely waxy or like very little at all.
Freshness in olive oil is not simply about whether the bottle has passed its best-before date. That date is usually calculated from bottling rather than harvesting, which is why I always look for a harvest year where possible.
In the Northern Hemisphere, olives are generally harvested during the autumn and winter, with premium early-harvest oils usually produced during the earlier part of the season.
Once a bottle is opened, the oil is exposed to oxygen every time you use it.
This is why I would much rather see someone finish a good bottle generously over a couple of months than ration it by the teaspoon for a year.
I've written more about making good olive oil part of everyday eating in What happens when you eat extra virgin olive oil every day?
Does olive oil improve with age?
No.
Even exceptionally well-made oil gradually loses aroma, flavour and antioxidants over time.
A robust, high-polyphenol oil may retain its character for longer than a very delicate one, but neither improves by sitting in a cupboard.
Olive oil is not wine. Fresh is better.
What does “early harvest” mean?
An olive changes considerably as it ripens.
Early in the season, the fruit is green, firm and relatively low in oil. As it ripens, it becomes softer and darker and contains considerably more oil.
Early-harvest olive oil is made from olives picked while they are still green or just beginning to change colour.
This has an important consequence: you need considerably more olives to make a litre of oil.
Depending on the variety, season and ripeness, a litre of very early-harvest oil may require around 8–11kg of olives, while riper fruit can sometimes produce a litre from roughly 4–6kg.
The exact figures vary, but the principle is simple: early fruit produces considerably less oil.
The producer is sacrificing yield in return for freshness, intensity, aroma and, often, higher levels of phenolic compounds.
This is one of the reasons really good early-harvest olive oil costs more.
The flavour is often greener and more assertive, with notes such as tomato leaf, artichoke, herbs and green almond. There may also be bitterness and a peppery finish.
Later-harvest oils can be softer, sweeter and riper in style. They are not automatically poor quality. Ripeness is one of many choices a skilled producer makes, and a gentler oil can be exactly what you want with fish, baking, mayonnaise or delicate vegetables.
I generally prefer early-harvest oils because I love that vivid green character, but the best oil is the one that suits the food and the person eating it.
Taste what I mean
Finca la Torre Hojiblanca
This is a lovely example of the vivid green character I mean when I talk about early-harvest olive oil. Made from early-harvest Hojiblanca olives on Finca la Torre's organic and biodynamic estate in Andalucía, it has notes of cut grass, citrus peel and green almond with a gentle peppery finish.
Bitterness and pepperiness are usually good signs
People are often surprised when an olive oil tastes bitter at the front of the mouth or catches slightly at the back of the throat.
This is especially common if they are used to mild supermarket oils.
Bitterness and pungency are recognised positive sensory attributes in extra virgin olive oil. They are often associated with fresh green fruit and phenolic compounds, although their intensity varies enormously according to olive variety, ripeness and production style.
A robust Picual or Coratina may be distinctly bitter and peppery.
A softer Arbequina can be fragrant, fruity and almost sweet.
Both may be excellent.
The important distinction is between pleasant bitterness and a defect.
Good bitterness feels fresh and food-like: think radicchio, rocket, artichoke or green almond skin.
A rancid oil tastes tired and stale and can remind you of old nuts, wax crayons or putty.
And pepperiness is not a measure of acidity.
You cannot taste free acidity in olive oil. That sharp tickle in your throat is a sensory characteristic, not the oil “burning” because it is acidic.
SARAH'S TIP: Taste a spoonful of oil on its own as well as with a piece of bread. Bread is very good at hiding both defects and subtler flavours.
What are polyphenols?
Polyphenols are naturally occurring compounds found in olives and olive oil. They contribute to bitterness, pungency, antioxidant activity and the oil’s stability.
You will often see a total polyphenol figure expressed in milligrams per kilogram (mg/kg).
A higher number can indicate a more robust and potentially more stable oil, but it is not the only measure of quality. Laboratory methods can also differ, so figures are not always directly comparable.
Olive variety makes a significant difference.
Picual and Coratina, for example, are often naturally high in polyphenols, while Arbequina tends to produce a gentler style. Harvest timing, irrigation, climate, milling and storage also affect the final result.
There is an authorised EU health claim relating to olive oil polyphenols and the protection of blood lipids from oxidative stress. The claim can only be used when an oil contains the required amount of hydroxytyrosol and its derivatives, and it must be accompanied by information about the daily intake required to obtain the beneficial effect.
You will sometimes see this simplified to a figure of 250mg/kg, but laboratory methods and the compounds being measured can differ, so I always rely on the producer’s current analysis rather than treating one headline number as the whole story.
Many of the oils I select for Sarah & Olive are naturally very high in polyphenols, with some recording considerably higher figures.
But I don't think everyone needs to chase the highest number they can find.
If you love powerful, bitter and peppery oils, or are particularly interested in phenolic content, look for an oil with a recent analysis from the producer.
If you prefer a softer, more delicate oil, the bottle with the highest polyphenol figure may simply not be the oil you enjoy most.
For a much deeper explanation, read Why is everyone talking about polyphenols?
If high polyphenols are what you're looking for
You can explore my high-polyphenol extra virgin olive oil collection, which brings together the robust, early-harvest oils I currently stock.
One particularly useful oil for understanding the relationship between variety, bitterness, pungency and polyphenols is Coratina. I wrote about this unusual Spanish-grown Coratina after tasting it at an olive oil masterclass in Italy.
Acidity: important, but widely misunderstood
Free acidity is one of the chemical measures used to classify olive oil.
It refers to the percentage of free fatty acids, expressed as oleic acid. For an oil to qualify as extra virgin, free acidity must be no more than 0.8%.
Very high-quality oils often have substantially lower figures.
But lower acidity does not automatically mean better flavour.
It tells us something about the condition of the olives and how they were handled before and during production, but it does not provide a complete quality score.
And this is worth repeating:
You cannot taste free acidity.
An oil that tastes intensely peppery does not therefore have “high acidity”, and a very mild oil is not necessarily low in acidity.
“Cold pressed” and “first press”
These are two of the most successful phrases in olive oil marketing, partly because they sound reassuringly traditional.
The problem is that, for most modern premium olive oils, “first cold pressed” doesn't really make sense anymore.
Historically, olive paste was spread onto fibre mats and physically pressed. The first pressing produced the best liquid, while further pressing using additional heat or water extracted more.
Most high-quality modern extra virgin olive oil isn't produced that way.
Today, the olives are crushed into a paste, gently mixed and the oil separated using a centrifuge.
There is no first press because there is no press.
The term cold extraction is more relevant. Under EU labelling rules, it refers to oil obtained below 27°C using modern extraction methods.
Temperature matters because excessive heat can increase the amount of oil extracted while compromising some of its aromas and quality.
However, virtually every serious premium producer controls temperature carefully, so the words cold extracted alone don't tell me that an oil is exceptional.
I would put much more weight on:
- a clear harvest year;
- a named producer or estate;
- a specific olive variety;
- transparent origin;
- good storage and packaging;
- and, ultimately, how the oil smells and tastes.
If you're curious about why those production choices make premium oils more expensive, I've written about that too: explore more of my olive oil guides and stories.
Does colour tell you whether olive oil is good?
Not reliably.
Olive oil can range from vivid emerald green to pale gold depending on the olive variety, ripeness, natural pigments and production.
And while we all love how a brilliantly green oil looks on a plate, colour alone does not prove freshness or quality.
Equally, a golden oil is not necessarily old, poor quality or refined.
Professional olive oil tasters use dark blue or amber tasting glasses so that the colour of the oil does not influence their assessment.
At home, enjoy the colour.
Just don't use it as your quality test.
Your nose and your palate will tell you much more.
Want to put some of this into practice?
You don't need the most expensive olive oil on the shelf and you certainly don't need to buy every oil I sell. The useful thing is to work out how you actually use olive oil.
For everyday cooking
If you roast vegetables, cook fish, make dressings, bake or generally use olive oil with abandon, start with an oil you can afford to pour generously.
For tasting and finishing
If you're looking for the oils where variety, producer, harvest and complexity really come into their own, this is where I would start.
For high polyphenols
If you particularly enjoy robust, green, bitter and peppery oils—or want to explore oils with current producer analysis—I've brought them together here.
Explore High-Polyphenol Olive Oils →
Or let me choose for you
The Sarah & Olive Tasting Club is probably the nicest way to learn the differences for yourself. I choose a different premium Spanish extra virgin olive oil for each delivery, with tasting notes, information about the producer and ideas for using it.
Keep learning about olive oil
If you'd like to go a little further down the olive-oil rabbit hole, these are good places to continue:
About the author
Sarah Merrigan is the founder of Sarah & Olive and an olive oil sommelier. She works directly with Spanish producers, visits farms and mills and tastes each new harvest to choose the oils sold by Sarah & Olive.
Choosing an olive oil can feel complicated. There’s so much to think about: acidity, polyphenols, harvest dates, dark bottles, early harvesting and cold extraction. Then you have people who say you should never cook with extra virgin olive oil, while others use it for almost everything. There are gold medals, pictures of ancient olive trees and words such as premium, reserve and first press bandied about—but what do they actually mean?
Yes, there’s a lot to learn, but actually most of it is pretty simple and once you get your head around a few basic principles it gets a lot easier.
I started Sarah & Olive because I loved olive oil and knew that it was tricky to track down the good stuff. I also wanted customers to better understand what they were buying, how they would use it and why some olive oils taste so much better than others.
The first thing I had to do was learn all this myself, so over the years I’ve done tasting courses, become an olive oil sommelier, visited farms and mills, had countless conversations with producers and other people in the business and always had a slightly unreasonable number of open bottles in my kitchen.
This is the guide I wish I had when I started.
It explains what extra virgin olive oil actually is, what matters when you buy it, how to taste and use it and why knowing about variety, freshness and the people making it is far more helpful than most of the language printed on the label.
If you remember one thing
A good extra virgin olive oil should smell fresh and taste alive.
The most important thing to know about extra virgin olive oil
That applies whether the oil is light and delicate, complex and herbaceous or robust and peppery. When you smell it, there should be something recognisably fresh there—perhaps grass, green almond, tomato leaf, herbs, apple or softer ripe fruit.
If an oil smells waxy, like old nuts or crayons, it is probably rancid. An oil that smells of almost nothing may be old, poorly stored or simply made in a flatter style, but it won’t give you the fresh, lively character I look for.
A fresh oil may also have some bitterness on the tongue or a peppery catch at the back of the throat. These are positive characteristics and are often associated with the naturally occurring phenolic compounds in the oil.
That freshness is what lifts a bowl of beans, a tomato, a piece of bread or a plate of pasta and makes the simplest food taste as though considerably more has happened to it.
What is extra virgin olive oil?
At its simplest, extra virgin olive oil is the oil extracted from fresh olives using only mechanical processes, without the chemical refining used to correct lower-grade oils.
“Mechanical” refers to the crushing, mixing and separation of the oil—not necessarily to how the olives are picked. Olives may be harvested by hand or with carefully managed machinery.
What really matters is that the fruit remains in good condition and reaches the mill quickly.
These days, the best olive oil is made fast. Olives are harvested efficiently and not left sitting around in the sun where they will start to deteriorate. They are taken to the mill as quickly as possible and processed at carefully controlled temperatures, with exposure to oxygen kept to a minimum.
In a nutshell, extra virgin olive oil is fresh olive juice that has been handled well from the grove to the bottle.
That sounds simple, but olives are exceptionally unforgiving.
Once picked, they begin to deteriorate. If they are bruised, left sitting in warm heaps or fail to reach the mill quickly, the quality of the resulting oil suffers. A producer can grow wonderful olives for an entire year and lose much of that work during the hours between harvesting and milling.
The best producers are obsessed with these details. Olives are picked carefully—and quickly—transported in ventilated crates or trailers and milled as fast as possible, often within a few hours.
Meet the maker: If you want to see what this looks like in practice, read about my visit to Finca la Torre and Víctor Pérez Serrano’s pursuit of exceptional olive oil.
What is the difference between extra virgin, virgin and ordinary olive oil?
This is one of the more confusing parts of buying olive oil because the bottles can look very similar.
Extra virgin olive oil
Extra virgin olive oil is produced mechanically and must meet the highest chemical and sensory grade.
Among the requirements, it must have free acidity of no more than 0.8%, expressed as oleic acid. This is one indication of the condition of the fruit and how it was handled before and during production, but it is not a complete measure of quality.
And importantly, extra virgin status is not decided by chemistry alone.
The oil also undergoes sensory assessment by a trained tasting panel. It must show fruitiness and be free from the sensory defects that would place it in a lower category.
An oil can perform well in chemical tests but still taste stale, musty, fermented or otherwise faulty.
Virgin olive oil
Virgin olive oil is also produced mechanically, but it may have free acidity of up to 2% and/or sensory defects that prevent it from qualifying as extra virgin.
Olive oil
A bottle labelled simply “olive oil” is a different product.
It generally contains olive oil that has undergone refining to remove defects, blended with some virgin or extra virgin olive oil to add flavour and colour.
Refining produces a much more neutral oil and removes much of the aroma, flavour and character that make a good extra virgin olive oil so interesting.
GOOD TO KNOW: “Pure olive oil” sounds impressive, but it is not a higher grade than extra virgin. It generally refers to refined olive oil blended with some virgin olive oil.
Olive oil is a fruit juice
This is probably the most useful way to think about it.
Olives are fruit, and extra virgin olive oil is their juice.
Like other fresh foods, olive oil is at its best when it is fresh and, because a good extra virgin olive oil has not been refined, it needs to be protected and looked after properly.
For a long time, we tended to think about olive oil in much the same way as other cooking oils. I think this is a mistake.
A good extra virgin olive oil has much more in common with fresh produce.
It has a harvest season, an olive variety and a place of origin. Its flavours change according to the ripeness of the fruit, the weather, farming practices and the decisions made during milling.
And unlike a neutral refined oil that can sit forgotten at the back of the cupboard, a good extra virgin olive oil is something to use while it is still fresh.
As a general buying rule, I look for oil from the most recent harvest and aim to use it while it still has all that wonderful freshness and character.
Once you start thinking of olive oil as fruit juice, several things make much more sense:
- Freshness matters.
- Light, heat and air damage it.
- Different olive varieties taste different.
- Knowing the harvest date is very useful. Always try to buy the most recent harvest.
- An open bottle is meant to be used, not admired indefinitely.
It also explains why good oils can smell of things that were never added to them: tomato leaf, freshly cut grass, green almond, apple, herbs, artichoke, banana or olive leaf.
These are natural aromas created by the fruit and the production process.
There isn’t any tomato or grass in the bottle, in the same way that a wine described as tasting of blackberry does not contain a handful of actual blackberries.
Why fresh olive oil tastes different
The first thing I notice when a really fresh oil is poured is the smell.
It might be grassy and intensely green or softer and fruitier, but it smells alive.
An old or tired oil tends to smell flat, vaguely waxy or like very little at all.
Freshness in olive oil is not simply about whether the bottle has passed its best-before date. That date is usually calculated from bottling rather than harvesting, which is why I always look for a harvest year where possible.
In the Northern Hemisphere, olives are generally harvested during the autumn and winter, with premium early-harvest oils usually produced during the earlier part of the season.
Once a bottle is opened, the oil is exposed to oxygen every time you use it.
This is why I would much rather see someone finish a good bottle generously over a couple of months than ration it by the teaspoon for a year.
I've written more about making good olive oil part of everyday eating in What happens when you eat extra virgin olive oil every day?
Does olive oil improve with age?
No.
Even exceptionally well-made oil gradually loses aroma, flavour and antioxidants over time.
A robust, high-polyphenol oil may retain its character for longer than a very delicate one, but neither improves by sitting in a cupboard.
Olive oil is not wine. Fresh is better.
What does “early harvest” mean?
An olive changes considerably as it ripens.
Early in the season, the fruit is green, firm and relatively low in oil. As it ripens, it becomes softer and darker and contains considerably more oil.
Early-harvest olive oil is made from olives picked while they are still green or just beginning to change colour.
This has an important consequence: you need considerably more olives to make a litre of oil.
Depending on the variety, season and ripeness, a litre of very early-harvest oil may require around 8–11kg of olives, while riper fruit can sometimes produce a litre from roughly 4–6kg.
The exact figures vary, but the principle is simple: early fruit produces considerably less oil.
The producer is sacrificing yield in return for freshness, intensity, aroma and, often, higher levels of phenolic compounds.
This is one of the reasons really good early-harvest olive oil costs more.
The flavour is often greener and more assertive, with notes such as tomato leaf, artichoke, herbs and green almond. There may also be bitterness and a peppery finish.
Later-harvest oils can be softer, sweeter and riper in style. They are not automatically poor quality. Ripeness is one of many choices a skilled producer makes, and a gentler oil can be exactly what you want with fish, baking, mayonnaise or delicate vegetables.
I generally prefer early-harvest oils because I love that vivid green character, but the best oil is the one that suits the food and the person eating it.
Taste what I mean
Finca la Torre Hojiblanca
This is a lovely example of the vivid green character I mean when I talk about early-harvest olive oil. Made from early-harvest Hojiblanca olives on Finca la Torre's organic and biodynamic estate in Andalucía, it has notes of cut grass, citrus peel and green almond with a gentle peppery finish.
Bitterness and pepperiness are usually good signs
People are often surprised when an olive oil tastes bitter at the front of the mouth or catches slightly at the back of the throat.
This is especially common if they are used to mild supermarket oils.
Bitterness and pungency are recognised positive sensory attributes in extra virgin olive oil. They are often associated with fresh green fruit and phenolic compounds, although their intensity varies enormously according to olive variety, ripeness and production style.
A robust Picual or Coratina may be distinctly bitter and peppery.
A softer Arbequina can be fragrant, fruity and almost sweet.
Both may be excellent.
The important distinction is between pleasant bitterness and a defect.
Good bitterness feels fresh and food-like: think radicchio, rocket, artichoke or green almond skin.
A rancid oil tastes tired and stale and can remind you of old nuts, wax crayons or putty.
And pepperiness is not a measure of acidity.
You cannot taste free acidity in olive oil. That sharp tickle in your throat is a sensory characteristic, not the oil “burning” because it is acidic.
SARAH'S TIP: Taste a spoonful of oil on its own as well as with a piece of bread. Bread is very good at hiding both defects and subtler flavours.
What are polyphenols?
Polyphenols are naturally occurring compounds found in olives and olive oil. They contribute to bitterness, pungency, antioxidant activity and the oil’s stability.
You will often see a total polyphenol figure expressed in milligrams per kilogram (mg/kg).
A higher number can indicate a more robust and potentially more stable oil, but it is not the only measure of quality. Laboratory methods can also differ, so figures are not always directly comparable.
Olive variety makes a significant difference.
Picual and Coratina, for example, are often naturally high in polyphenols, while Arbequina tends to produce a gentler style. Harvest timing, irrigation, climate, milling and storage also affect the final result.
There is an authorised EU health claim relating to olive oil polyphenols and the protection of blood lipids from oxidative stress. The claim can only be used when an oil contains the required amount of hydroxytyrosol and its derivatives, and it must be accompanied by information about the daily intake required to obtain the beneficial effect.
You will sometimes see this simplified to a figure of 250mg/kg, but laboratory methods and the compounds being measured can differ, so I always rely on the producer’s current analysis rather than treating one headline number as the whole story.
Many of the oils I select for Sarah & Olive are naturally very high in polyphenols, with some recording considerably higher figures.
But I don't think everyone needs to chase the highest number they can find.
If you love powerful, bitter and peppery oils, or are particularly interested in phenolic content, look for an oil with a recent analysis from the producer.
If you prefer a softer, more delicate oil, the bottle with the highest polyphenol figure may simply not be the oil you enjoy most.
For a much deeper explanation, read Why is everyone talking about polyphenols?
If high polyphenols are what you're looking for
You can explore my high-polyphenol extra virgin olive oil collection, which brings together the robust, early-harvest oils I currently stock.
One particularly useful oil for understanding the relationship between variety, bitterness, pungency and polyphenols is Coratina. I wrote about this unusual Spanish-grown Coratina after tasting it at an olive oil masterclass in Italy.
Acidity: important, but widely misunderstood
Free acidity is one of the chemical measures used to classify olive oil.
It refers to the percentage of free fatty acids, expressed as oleic acid. For an oil to qualify as extra virgin, free acidity must be no more than 0.8%.
Very high-quality oils often have substantially lower figures.
But lower acidity does not automatically mean better flavour.
It tells us something about the condition of the olives and how they were handled before and during production, but it does not provide a complete quality score.
And this is worth repeating:
You cannot taste free acidity.
An oil that tastes intensely peppery does not therefore have “high acidity”, and a very mild oil is not necessarily low in acidity.
“Cold pressed” and “first press”
These are two of the most successful phrases in olive oil marketing, partly because they sound reassuringly traditional.
The problem is that, for most modern premium olive oils, “first cold pressed” doesn't really make sense anymore.
Historically, olive paste was spread onto fibre mats and physically pressed. The first pressing produced the best liquid, while further pressing using additional heat or water extracted more.
Most high-quality modern extra virgin olive oil isn't produced that way.
Today, the olives are crushed into a paste, gently mixed and the oil separated using a centrifuge.
There is no first press because there is no press.
The term cold extraction is more relevant. Under EU labelling rules, it refers to oil obtained below 27°C using modern extraction methods.
Temperature matters because excessive heat can increase the amount of oil extracted while compromising some of its aromas and quality.
However, virtually every serious premium producer controls temperature carefully, so the words cold extracted alone don't tell me that an oil is exceptional.
I would put much more weight on:
- a clear harvest year;
- a named producer or estate;
- a specific olive variety;
- transparent origin;
- good storage and packaging;
- and, ultimately, how the oil smells and tastes.
If you're curious about why those production choices make premium oils more expensive, I've written about that too: explore more of my olive oil guides and stories.
Does colour tell you whether olive oil is good?
Not reliably.
Olive oil can range from vivid emerald green to pale gold depending on the olive variety, ripeness, natural pigments and production.
And while we all love how a brilliantly green oil looks on a plate, colour alone does not prove freshness or quality.
Equally, a golden oil is not necessarily old, poor quality or refined.
Professional olive oil tasters use dark blue or amber tasting glasses so that the colour of the oil does not influence their assessment.
At home, enjoy the colour.
Just don't use it as your quality test.
Your nose and your palate will tell you much more.
Want to put some of this into practice?
You don't need the most expensive olive oil on the shelf and you certainly don't need to buy every oil I sell. The useful thing is to work out how you actually use olive oil.
For everyday cooking
If you roast vegetables, cook fish, make dressings, bake or generally use olive oil with abandon, start with an oil you can afford to pour generously.
For tasting and finishing
If you're looking for the oils where variety, producer, harvest and complexity really come into their own, this is where I would start.
For high polyphenols
If you particularly enjoy robust, green, bitter and peppery oils—or want to explore oils with current producer analysis—I've brought them together here.
Explore High-Polyphenol Olive Oils →
Or let me choose for you
The Sarah & Olive Tasting Club is probably the nicest way to learn the differences for yourself. I choose a different premium Spanish extra virgin olive oil for each delivery, with tasting notes, information about the producer and ideas for using it.
Keep learning about olive oil
If you'd like to go a little further down the olive-oil rabbit hole, these are good places to continue:
About the author
Sarah Merrigan is the founder of Sarah & Olive and an olive oil sommelier. She works directly with Spanish producers, visits farms and mills and tastes each new harvest to choose the oils sold by Sarah & Olive.