The Mediterranean diet is healthy for a whole host of reasons, but its reliance on olive oil is one of the major contributing factors. Countless studies have shown that consuming olive oil on a regular basis can benefit our hearts and brains, and reduce our risk of health issues like cardiovascular disease and cancer. Couple those benefits with the deliciously bitter, grassy taste and it’s hardly surprising that many of us are willing to fork out serious cash on a good bottle of the stuff.

But beyond knowing that olive oil equals good, how much do you really know about it? While you might have guessed that the cheaper, mass-produced olive oils probably aren’t as high quality as the artisan ones, did you know that the way olive oil is produced can affect its health benefits? And that some olive oils offer little to no nutrients? 

One person who knows a lot about this is Sarah Vachon, an olive oil sommelier and founder of the olive oil subscription service Citizens of Soil. Her day-to-day job involves travelling around the world to find the best tasing olive oils for the company’s olive oil club, using only female producers who practise regenerative agriculture. She’s passionate about the health benefits of olive oil, which is why you’ll find the level of polyphenols – the antioxidant compounds which deliver many of the health benefits associated with olive oil – indicated on any Citizens of Soil olive oil bottle.

So, to help you find olive oils that taste good and do good, we asked Vachon to tell us a little bit more about the world of olive oil and what we should be looking for on the shelf.  

You might be surprised to learn that no, not all olive oils are healthy or good for us. To make that statement, you need to get a bit more specific with the type of olive oil you’re talking about. In particular, you need to stick to extra virgin olive oils.

“Extra virgin olive oil has been a superfood since antiquity and has been celebrated for its healing and nutritional powers for just as long,” Vachon says. “Extra virgin olive oil is just the juice of crushed and squeezed olives. By law, it must be produced without heat or chemicals, which is what separates it from all the other edible oils. It’s a vibrant, fresh product teeming with antioxidants and has proven health benefits.”

Virgin olive oils can offer some of these health benefits, but the difference in the way they are produced and tested (more on that later) can lead to them being less potent in terms of their health offering and flavour.

And olive oils without the virgin label are a whole different ball game, Vachon adds: “Outside the virgin olive oil category, most olive oils are refined, highly processed, bleached and deodorised – all aimed at creating a shelf-stable, lifeless oil at a lower cost.

“Comparing virgin and regular olive oil is like comparing freshly squeezed orange juice to orange soda. One provides nutrition on multiple levels, while the other… well, it’s soda.” 

While both extra virgin and virgin olive oil are produced in the same way, extra virgin tends to be of a higher quality due to the extra testing and analysis it has to undergo.

“Virgin olive oil is made the same way as extra virgin – crafted without the use of heat, chemicals or solvents,” Vachon explains. “Both are produced through purely mechanical processes – crushing, squeezing and extracting the juice from the olives.

“The difference is that extra virgin olive oil undergoes a lab and sensory analysis to determine its quality and ensure there aren’t any defects. In the case of virgin, the olives going in might not be as high quality or the milling might not be as clean or precise, and that can lower the grade. This is why we often liken extra virgin olive oil to a fresh fruit juice: it undergoes no further heat or chemical treatments. It remains vibrant, teeming with antioxidants and boasts a shelf-life of approximately 18–24 months when unopened.” 

In this way, while all virgin olive oils are made using a process that retains the health benefits, extra virgin olive oils have an extra stamp of approval – so you know you’re getting the highest quality olive oil possible. 

It’s worth noting that the levels of antioxidants found in extra virgin olive oils can still vary, but all extra virgin olive oils will deliver them alongside healthy fats. 

We’ve already gone over the difference between regular, virgin and extra virgin olive oils – but what makes some extra virgin olive oils healthier than others?

It’s the levels of antioxidants – in this case, polyphenols – that are contained within the oil. “Only the ‘freshness’ of an extra virgin olive oil can give you a rich source of polyphenols, the antioxidants that make this type of oil so powerful,” Vachon says. “While polyphenols exist in different levels across loads of different plants that we eat, some, like oleocanthal, are only found in extra virgin olive oil.”

She continues: “This particular compound is one of the most researched polyphenols in olive oil and has tremendous evidence around its anti-inflammatory benefits.”

While all extra virgin olive oils will deliver these polyphenols, some are produced specifically to retain as many polyphenols as possible, making them superior for your health. Things that can affect the polyphenol levels in an oil include the way in which it was farmed (healthy soils make healthy oils), when it was harvested, the varieties of olives used in its production and how it was milled. The oils higher in polyphenols tend to have a more bitter taste, so some producers prefer to opt for a slightly lower count to produce a milder flavour, while others prefer to try and retain as many polyphenols as possible. 

The question is: how can you tell a high-polyphenol extra virgin olive oil from the other extra virgin olive oils? Vachon recommends looking out for when the olives were harvested (you want an early harvest, which is between September and October in the northern hemisphere, from the most recent year) and opting for oils made from specific varieties such as koroneiki in Greece, picual in Spain and coratina in Italy.

To maximise the polyphenol count of your oils once you’re home, you’ll need to make sure to consume your oil within three months and keep it out of the sunlight; it’s for this reason that oils sold in darker bottles are better for retaining high polyphenols. 

If you can’t find details about the polyphenol levels or olive varieties on your extra virgin olive oil bottle, it is possible to identify a good quality extra virgin olive oil from taste alone.

“There’s a holy trinity of things we can smell and taste for that assure us we’ve got a nice extra virgin olive oil on our hands,” Vachon says. “It’s best to pour a little of the oil into a small cup or wine glass to swirl around and have a smell, followed by a taste.”

The three things you’re looking for are:

1. Fruitiness

“This quality is called ‘fruitiness’ in the olive oil space, but it doesn’t actually just mean a fruity smell or flavour,” Vachon says. “Extra virgin olive oil should smell ‘alive’ – so not like an old book, metallic or waxy. Instead, we’re looking for plant aromas. Common ones here include things like fresh-cut grass, herbs, tomatoes, artichokes and apples.”

2. Bitterness

“This sensation can range from a sharp astringency to something slight on the palate,” Vachon says. “It often gives olive oil that ‘boldness’ or robustness that people associate with some oils from the south of Italy or Tuscany. But it can also be mild with only a small indication – and that’s OK, too. Bitterness isn’t required to be strong in an award-winning oil, but it is considered a positive attribute for extra virgin olive oil to have.”

3. Pepperiness (often called pungency)

“Whether it’s a little tingle in the back of the throat or causes a full-on coughing fit, that pepperiness represents so much,” Vachon explains. “It can feel like cracked black pepper or even a full-on chilli and comes from the presence of the oleocanthal.” 

Images: Getty