As a pantry staple, olive oil is one of the oldest, most celebrated foods. A major component of the Mediterranean diet, olive oil—especially extra virgin—is heart healthy thanks to high amounts of monounsaturated fats and polyphenols (which have antioxidant properties). The latter compounds are resistant to high heat, which makes olive oil a healthy choice for cooking.
It’s also one of the most regulated in the food industry, according to Fil Bucchino, a Toronto-based olive oil expert who is the only Canadian in the Italian National Directory of Virgin and Extra Virgin Olive Oil Experts, and the co-producer of the award-winning documentary, Obsessed with Olive Oil. To say he’s an expert in all things EVOO is truly an understatement.
Here’s what you need to know about buying, storing and enjoying olive oil.
There are around 2,000 olive cultivars (a.k.a. varieties of olives) in the world, with most regions having their own native cultivar. Each one has its own physical, sensory and chemical characteristics.
Related: Our Favourite Olive Oils For Cooking, Dipping and Drizzling
All olives start out green in hue, and after a certain level of maturation become black (so, green olives are harvested when the olives are unripe, while black ones are harvested when they’re naturally ripe). All olives are edible and can be consumed as table olives or used to make oil. Additionally, each cultivar grows to a different size, with some having more meat (pulp)—preferable for eating—while others have more oil.
Generally, an early-harvest olive isn’t ripe and would tend to be more bitter (due to its polyphenol content), pungent and strong tasting, whereas a later harvest cultivar is more mature, mellow and buttery. Oils made from the latter don’t last as long as the former because they contain fewer phenolic compounds.
How is olive oil made?
To make olive oil, olives are crushed in a machine; the resulting paste is then put through a centrifugal process which separates the oil from water and solids. According to Bucchino, all modernized processes for olive oil production extract the oil at temperatures below 27C. (The term “first cold pressed,” he says, is nothing more than marketing lingo.)
Olive oils can either be made from one type of olive—known as monocultivar oils—or a blend of different cultivars from the same region to achieve a specific flavour profile.
Olive oils range in colour from yellow to green—though Bucchino notes that colour has no impact on flavour or quality—and can be filtered or unfiltered. Unfiltered oil is usually visibly cloudy and has a short shelf life.
What’s the difference between EVOO and regular olive oil?
Olive oils are designated in different grades, and each has a distinct flavour, aroma and nutritional profile.
Extra virgin olive oil
EVOO is the highest grade of olive oil and is deemed free of taste defects by inspectors. It’s also the grade that has the most health benefits due to minimal processing, which preserves its polyphenols and micronutrients. The most flavourful of the lot, it comes in various styles from delicate to robust and in a complex range of bitter, peppery spice or fruity flavours. EVOO can be used for virtually any purpose, including cooking, baking (like this delicious Grapefruit Olive Oil Cake) and frying. It can also be drizzled on fish, salads and ice cream.
Virgin olive oil
Virgin olive oil is produced like EVOO but is allowed to have some minor flavour defects. It is just as versatile as EVOO.
Olive oil is made from blending virgin olive oil with refined virgin olive oil (the lowest grade of olive oil, which has been treated to remove flavour defects). It’s lighter in colour and more neutral in flavour and aroma than EVOO, and occasionally has green colouring added. Although it has less beneficial health properties than EVOO, it’s still more nutritious than most other cooking oils and can be used in recipes where you don’t want that classic olive oil flavour.
What types of cooking is olive oil best for?
Olive oil has a high smoke point for an unrefined oil—around 177C to 210C, a range that encompasses most types of cooking. Best used in no-cook or low- to medium-high cooking, depending on the grade, you can sauté, roast, stir fry, bake and even deep fry with quality EVOO. (Albeit the latter use could get pricey.)
“If you want to cook or fry with olive oil for health reasons, you should definitely be cooking and frying with a fresher, more expensive, more phenolic-charged olive oil because it gives you more defense against heat,” says Bucchino referencing the protective polyphenols in EVOO that makes it more stable, resulting in fewer oxidative by-products when heated. “However, an oil that is [high] in polyphenols will definitely flavour your food.”
The general rule is that mild or delicately flavoured olive oils made from riper, later harvest olives are great for cooking and baking, drizzled on white fish, mild salads and vegetables, or for bread dipping.
Medium or fruitier olive oils have a bit of green and pepperiness to them and are fantastic for the above uses as well as drizzled on cooked vegetables, potatoes, rice, pasta, cheese and even desserts.
Robust or intense olive oils that are very green and peppery can hold up against flavourful dishes such as grilled meats and vegetables, hearty soups and stews.
Any monocultivar or premium blend is good used as a finishing oil.
Where does the best olive oil come from?
There’s a misconception that the best olive oils only come from Italy or France. However, Spain, Greece, California, Tunisia and Brazil have all gained recognition for the unique flavour profiles of their olive oils. Above all, says Bucchino, good olive oil relies on the producer, not the country of origin.
How to buy and store olive oil
Buy olive oil in small amounts
The golden rule: Buy only what you’re going to use up relatively quickly. Bucchino says that opening a bottle of olive oil is “no different than when opening a bottle of wine, as soon as you open a bottle, oxygen is going to get into it.” For this reason, 500-mL bottles are best for most households.
Buy olive oil packaged in dark glass
Since olive oil is sensitive to light and rapid changes in temperature, a dark glass bottle is ideal, as clear plastic permits light and metal conducts heat.
He also recommends bag-in-box packaging: “The bag keeps out light, [and] every time you remove oil from the bag, it keeps the oxygen out too.” (That said, finding olive oil that is packaged this way is tricky in Canada.)
Store olive oil away from heat
Bucchino notes that the ideal temperature for olive oil is between 16°C to 17°C. Store in a cool dark place, like a cupboard, as opposed to next to your stove—which he says is “the worst thing” you can do. Also do not store in the fridge.
“At the end of the day, it’s good to consume the oil within the year that it’s produced, says Bucchino. “As long as you keep it in a cupboard in the dark, you’re good to go.”