Olive oil is a cooking oil extracted from olives, the fruit of a small tree from the Oleaceae family found mostly on the Mediterranean Sea’s coast. Olive oil is a pantry staple in most households and the most popular vegetable oil sold on the market today.
So here’s everything you could possibly want to know about it.
Olive oil is used in salad dressings, as a cooking oil for sautéing vegetables, and as an ingredient in baking. It can even be used as fuel for a do-it-yourself oil lamp. Outside of the home kitchen, olive oil is also used in skincare, drug-making, and soap-making.
Olive oil is commercially made in a fairly small number of countries, which are also its biggest exporters worldwide. Olive oil is made in Spain, Portugal, Italy, and Greece in Europe, as well as Morocco and Turkey in the Middle East. In the United States, it’s produced in the state of California (since olive trees grow on the Pacific coast).
Most supermarkets, grocery stores, and mom-and-pop shops carry at least several brands of olive oil. Look for olive oil in the cooking oils and vinegar aisle. It’s sold in 8.4, 16.9, 33.8, 48, 51, and 67.6-ounce bottles and 101.4-ounce tin cans.
How to Choose Olive Oil
When shopping for olive oil in the supermarket, choose an extra virgin olive oil in a dark glass bottle or tin with the most recent best-by and harvest dates.
Buy olive oil from producers you’ve researched and retailers you can trust. Ideally, support your local community by shopping for local products at delis or mom-and-pop shops.
If you live in the U.S., keep in mind that Californian olive oil is one of the best in the world.
The Types of Olive Oil
There are different types of olive oil depending on how it was extracted from the olives and how pure the resulting oil is.
|Variety||Quality||Texture||Taste||Acidity Level||Smoke Point|
|Extra virgin olive oil||Highest||Thick and creamy||Bitter, nutty, and grassy||0.8%||375°F (190°C)|
|Virgin olive oil||High to medium||Clear and oily||Bitter||0.8-2%||410°F (210°C)|
|Light olive oil||Medium to low||Light and oily||Bitter, slightly tasteless||1%||465°F (240°C)|
|Olive pomace oil||Lowest||Thin||Relatively tasteless||1%||465°F (240°C)|
The highest-quality olive oil comes from the first squeeze of the freshly-harvested olives. It has the lowest acidity levels and smoke point.
The more aggressive the processing to extract oil from the olives, the lesser its quality. Additional processing brings the acidity level down and raises the oil’s smoke point.
If you don’t know what acidity level and smoke point mean (and why they’re important), keep on reading. I’ll explain this to you later on in this article.
Here’s what you need to know about each of these types of olive oil.
Extra Virgin Olive Oil
Extra virgin olive oil is the purest and highest quality olive oil you can buy in the supermarket. It’s extracted from the olives using only mechanical means without the use of chemicals.
For an olive oil to be considered extra virgin, it must be 100% pure. It must be cold pressed and have a free fatty acid content no higher than 0.08%. In addition, it must have no defects of aroma and flavor—and come with a genuine taste of green or ripe olives.
As you can probably tell after reading this definition, the unfortunate reality for consumers like you and me is that most olive oils sold as extra virgin olive oils in the supermarket… would never really pass the test.
But I’ll get to that later on in this article (and give you my best tips for how to select olive oils when you’re out shopping).
To produce extra virgin olive oil, the olives are harvested, washed, and cleaned from any twigs and leaves that might have been picked up during harvesting.
The olives are then ground into a paste using stone mills and at room temperature.
Next, the olive oil paste passes through a kneading machine. The kneading machine helps to separate the olive oil from the water in the olive paste.
Finally, the olive paste is spread on discs and each disc is put on top of the other (in a way that very much resembles how a döner kebab is made).
The extra virgin olive oil is extracted as the olive paste discs are pressed down using a hydraulic press. As this happens, heat is naturally released. To produce the highest-quality product, the temperature of the olives during pressing should never exceed 120°F (49°C).
This type of extraction is known as the cold press and the olive oil that comes out of it is called cold pressed olive oil. Cold pressed olive oils retain their genuine taste, aroma, and nutrients.
Here’s how this process looks like inside a traditional Italian olive oil mill:
More modern production methods that involve using centrifuges, which produce purer and cleaner oil, have started to gain ground among olive oil producers in recent years.
Virgin Olive Oil
As its higher-grade namefellow, virgin olive oil is extracted using solely mechanical means without chemical solvents.
Virgin olive oil is cold pressed olive oil that doesn’t meet the higher standards of extra virgin olive oil. In general, most olive oils of this type have an acidity level between 0.8% and 2% and come with a slightly inferior texture, flavor, and aroma.
Think of it as the equivalent of buying scratch and dent appliances. Virgin olive oil is still pretty good olive oil, but it’s just not going to look, taste, or smell as good as the original. It’s probably going to be less viscous, more bitter, and not as aromatic compared to extra virgin olive oil.
After the first press, there’s 5-8% more oil to be extracted from the olives. However, this can only be done using methods that involve higher temperatures and chemical solvents.
From this stage on, the oil extracted from the olives can no longer be called “olive oil.” It becomes “pomace oil” or “olive pomace oil,” which translates as olive pulp oil.
Light Olive Oil
Light olive oil, sometimes called extra light olive oil, takes its name not because it’s a dietary alternative to other olive oils, but because it’s lighter (lesser-grade) in texture, color, and taste.
Typically, light and extra light olive oil are a blend of 5-10% virgin olive oil and 90-95% refined olive oil.
The refined olive oil, which makes up the majority of this type, is treated with heat and chemicals to smooth out its imperfections of taste and smell.
As a result, it’s not as rich in micronutrients as extra virgin and virgin olive oil (but is still relatively healthy compared to other cooking oils).
Pomace oil, also known as olive pomace oil, is the cooking oil extracted from the olive pulp after the first press.
According to the International Olive Council, an international organization that sets standards for table olives and olive oil, pomace oil shouldn’t be called olive oil.
In olive oil production, the term “pomace” means the olive residue obtained after the pressing or centrifugation of the olive paste.
The olive pomace consists of the skins, pulps, and pits of the olives and contains approximately 5-8% of the total oil that can be extracted from a harvest.
To extract the remaining oil from the pomace, producers use a chemical solvent called hexane. Hexane is a constituent of gasoline. It’s colorless, odorless, and has a boiling point of approximately 156°F (69°C).
The chemical extraction of pomace oil is achieved in three phases: the pomace is prepared, the remaining oil is extracted from it using hexane, and the pulp is desolventized.
Blended Olive Oil
As you read into the labels of olive oils sold at grocery stores, you’ll notice that most of the bottles and tins are blended olive oil.
More than 1,000 olive varieties grow across the world, each with its unique characteristics. Blended olive oils consist of a mix of olive oils from more than one olive variety, region, and country.
For example, it’s not uncommon to see European olive oil blends from olives in Spain, Portugal, Italy, and Greece altogether. Blended olive oils are in no way inferior from olive oils made from one olive variety. Many excellent olive oils come from a blend.
Typically, olive oil producers blend olive oil for two reasons. First, it’s difficult to commercially produce large quantities of olive oil from the harvest of a single ranch. Second, blending an olive oil that’s high in polyphenols with one that isn’t will increase the stability and shelf life of the resulting oil.
What the Acidity Level of Olive Oil Means
Try to learn more about olive oil on the Internet, and one of the things you’ll repeatedly read and hear is that the acidity level of an olive oil is an important factor for its quality. Try to understand exactly why, and you’ll come out almost empty-handed.
The curious soul that I am, I fell down the rabbit hole as I was researching the topic for post. After hours of digging into scientific journals, research papers, and books on olive oil production, here’s what I managed to dig out.
Free Fatty Acids
Fatty acids are a family of molecules in the so-called lipid micronutrient category (lipids is a broader term for fats, oils, and wax).
Fatty acids contain adenosine triphosphate, an organic compound that provides your cells with the energy to power much of their survival and growth.
Free fatty acids are a source of energy for your body that readily circulates in your blood. Any cell with an organelle called mitochondria can pick them up from your blood and feed on them.
While free fatty acids are essential for your body to function, a number of medical studies have linked elevated levels of free fatty acids in the blood to insulin resistance.
One observational study of 16 participants found that elevated levels of free fatty acids in the blood are thought to raise the risk of cardiovascular disease by causing insulin resistance.
Consuming free fatty acids in your food ultimately raises the levels of free fatty acids in your blood. Simply said, you want to avoid eating ingredients and condiments with a high content of fatty acids.
Just as any other cooking oil, olive oil contains a certain amount of free fatty acids.
Acidity Levels of Olive Oils
The acidity level of an olive oil measures the amount of free fatty acids that it contains.
Acidity level is expressed as a percentage (%) and is measured as the total weight of free oleic acid per 100 grams of olive oil.
There’s an inverse relationship between the acidity level of an olive oil and its quality. The highest-grade olive oils have the lowest levels of acidity.
Extra virgin olive oil, the purest and highest-grade olive oil, has an acidity level of 0.08% or less. In comparison, virgin olive oil has an acidity level in the range anywhere from 0.08 to 2%.
What Is the Healthiest Olive Oil?
To get the healthiest olive oil, buy fresh extra virgin olive oil. You can tell how fresh a bottle of olive oil is by looking at the “harvest date.” It’s typically printed on the label or stamped on the glass.
Extra virgin olive oil is considered to be the healthiest olive oil. It’s extracted using mechanical means without chemical solvents, and conforms to the highest standards for acidity levels (0.08% oleic acid content or less), texture, flavor, and aroma.
“Olive oil,” Harvard Health reports, “is high in monounsaturated fatty acids, containing about 75% by volume.”
“When substituted for saturated fat, monounsaturated fats help lower your “bad” LDL cholesterol. The antioxidant and anti-inflammatory properties of olive oil add benefits beyond cholesterol lowering.”
Olive oil also contains polyphenols, plant-based micronutrients believed to reduce morbidity and slow down the development of cardiovascular and neurodegenerative diseases.
According to a study of the antioxidants in Greek olive oils, extra virgin olive oil contains the most polyphenols. Refined oils from olives such as pomace oil are devoid of vitamins, polyphenols, phytosterols, and other low molecular natural ingredients.
Filtered vs. Unfiltered Olive Oil
Apart from the fact that you’ll have a hard time eating them raw (olives taste extremely bitter out of the tree), olives are very much like any other fruit: when you squeeze the juice from them without running it through a sieve, you’re going to end up with some pulp in your glass.
Olive oil is the freshly-extracted juice from the ripened fruit of the olive tree. When it hasn’t been filtered, its texture is viscous and murky. And the oil can contain tiny bits and pieces of olives or olive tree leaves.
The only difference between filtered and unfiltered olive oil is that the latter has a murkier appearance and a shorter shelf life. In other words, buy the kind whose taste and texture you like the most.
Once the olive oil gets bottled, those tiny particles of olives and leaves sink down to the bottom of the glass and continue to ferment as the oil ages. This sediment accelerates the oxidation of the olive oil once it’s opened, causing it to have a shorter shelf life.
Some consumers also dislike the cloudy look and silky texture of unfiltered olive oil—so producers have naturally adapted to their preferences. That’s why most of the bottles of olive oil at the cooking oils and vinegar aisle are filtered.
When it comes to their nutritional values or health benefits, there’s no significant difference between filtered and unfiltered olive oil made from the same olive harvest.
What Does It Mean When Olive Oil Smokes?
Every cooking oil has a smoke point, the temperature at which the oil stops to glisten and shimmer, and starts to break down and smoke.
Extra virgin olive oil has a smoke point of 375°F (190°C), compared to 410°F (210°C) for virgin olive oil and 465°F (240°C) for olive pomace oil.
When olive oil gets too hot and starts to smoke, it’s more than just a nuisance. This is the sign that the oil has started to break down.
When oil breaks down, it releases chemicals that can make your food taste unappealingly bitter. It can also emit harmful compounds for your body and toxic fumes in the air.
According to The Olive Oil Source, you shouldn’t worry too much about smoking olive oil. “Studies have shown oxidation and hydrogenation occurs to a lesser degree in olive oil than in other oils,” the website writes. “The amount of hydrogenation is miniscule and no home cook would ever experience this problem.”
Contrary to popular belief, extra virgin is completely safe for frying foods—as long as you don’t cook with it on high heat.
It’s true that olive oil has a relatively low smoke point when compared to other cooking oils. However, it’s a myth that the smoke point is so low, that olive oil is not fit for pan-frying.
The ideal temperature for pan-frying is considered by many to be 360°F (≈180°C), which is well below the smoke point of extra virgin olive oil.
Can Olive Oil Go Bad?
Extra virgin olive oil will keep its best quality for 12-18 months from the date they’re bottled. Lesser-grade olive oils like virgin olive oil and light olive oil last longer, typically 18-24 months from the bottling date.
Beyond its best-by date, olive oil goes rancid. To tell if a bottle of olive oil has gone rancid, taste and smell a teaspoon of it. If it tastes bitter or smells stale, it’s most probably no good.
There’s no need to worry about taste-testing an olive oil when you suspect it might have gone rancid. A small taste won’t harm your health in any way.
Some producers will extract olive oil and store it in barrels, occasionally for years, before bottling. This produces olive oil that’s safe to eat, but lesser-grade.
To make sure you get the freshest olive oil, look at its “best-by” date and “harvest” date.
The harvest date tells you when the olives were harvested (and, consequently, when the oil was extracted from them). The freshest olive oils have the most recent harvest dates.
How to Store Olive Oil
Here are my best tips for how to store olive oil so that it keeps its best qualities and you maximize its shelf life.
Keep Olive Oil in a Dark-Glass Bottle or Tin
Olive oil is natural and perishable. Keep olive oil in a cool and dry place.
Never expose olive oil to direct sunlight. As a rule of thumb, you shouldn’t store olive oil by a window and in clear glass or plastic.
Don’t store olive oil by a window or near your stove. Doing so will shorten its shelf life as you’re exposing it to sunlight and heat.
Protect olive oil from direct sunlight to maximize its quality and shelf life. Store olive oil in a dark place, like your pantry or inside a kitchen cabinet, in a dark glass bottle or a tin, making sure that the cap is tightly closed.
Should You Keep Olive Oil in the Fridge?
The ideal temperature for storing olive oil is 65°F (18°C).
In general, you can store olive oil at room temperature, which is slightly higher at 68-72 °F (20-22°C) depending on your location and climate.
There’s no need to store olive oil in the fridge. Olive oil will form crystals and solidify when it’s stored at cold temperatures. It will go back to its original state soon after it’s taken out from the fridge and its internal temperature rises.
Some consumers wrongly believe that refrigerating olive oil helps you test its authenticity. This is a myth. To get the best olive oil, buy extra virgin olive oil from a producer you can trust and with the most recent harvest and best-by dates.
Will Olive Oil Freeze?
Yes, olive oil will freeze.
Unlike water, which always freezes at 32°F (0°C) as it’s a pure substance, olive oil will freeze at different temperatures depending on the type of olive oil at hand.
Olive oil is a natural product and every batch is different depending on the harvest and the unique conditions of the production process. This is why there’s no single freezing temperature to serve as a rule of thumb for all olive oils.
Chilling or freezing olive oil won’t damage it in any way. The olive oil will simply solidify and turn into crystals because of its exposure to lower temperatures. You can safely bring chilled or frozen olive oil back to room temperature and use it as a condiment or cook with it.
Saving the Environment
Here’s what you need to know to protect the environment as you buy, eat, and cook with olive oil in your home kitchen.
Are Plastic Olive Oil Bottles Recyclable?
Most plastic olive oil bottles are made from polyethylene terephthalate (also known as plastic number 1, PET, or PETE plastic). This makes them generally recyclable and widely accepted by most recycling plants.
To find out what plastic your bottle of olive oil is made of, turn the bottle over and look at its bottom side. Find the recycling symbol, take a note of the number inside it, and compare it to your local community’s sustainability guidelines to determine if it’s eligible.
Are Glass Olive Oil Bottles Recyclable?
Glass olive oil bottles are recyclable.
Some glass olive oil bottles are considered too large and bulky. When that’s the case, take it to a recycling drop-off location in town.
Can You Recycle Olive Oil Tins?
Olive oil tins are recyclable.
However, whether you should put them in your curbside recycling bins or bring them to a recycling drop-off depends on your local community.
Some recycling programs will accept these types of containers mixed with other recyclable materials, and others not.
To determine how to best recycle olive oil tins, check with your local city or county recycling program.
My “Secret” Olive Oil Pick
For those of you who read this far, here’s my best olive oil pick. It’s kind of a secret because, unless you’ve scrolled through from the very start, few people typically get this far 🙂 .
California Olive Ranch 100% Extra Virgin Olive Oil is the best olive oil that you can buy if you live in the U.S. or Canada. Cold pressed and made from Californian olives, this oil has a wonderful grassy, buttery, and slightly fruity taste.
- 100% CALIFORNIA EXTRA VIRGIN OLIVE OIL: Award-winning California Olive Ranch 100% California Extra Virgin Olive Oil (EVOO), crafted from...
- STAPLE IN YOUR KITCHEN: Features well-rounded notes of a floral, buttery and fruity taste. Versatile across multiple applications - use it...
- DIET FRIENDLY: Our extra virgin olive oils are verified non-GMO by the Non-GMO Project, and certified kosher by Orthodox Union. It’s also...
Use this olive oil to dress salads, make marinades, sauté mushrooms, roast red meat and poultry, grill or pan-fry food, and even bake bread or pizza.