Olive oil explained: how to find the right bottle for you

When an olive is harvested earlier (whilst it is green, fresh and unripe), the oil is fruitier, more complex and contains more polyphenols. Polyphenols are important when describing the health benefits of olive oil – they are micronutrients with antioxidant properties that are thought to play a role in managing various illnesses, including diabetes, neurovascular disease and cardiovascular disease. Generally speaking, an early harvest guarantees an oil that contains the maximum level of polyphenols for good health.

If on the other hand, you pick a mature olive that is completely ripe, it will produce more oil but contain lower levels of polyphenols. Typically, farmers will leave olives on the tree until they’re nearly black so the oil yield will be higher. While oil made from those olives is still sweet, it lacks the bitter and fruity characteristics found in first-rate olive oils, and it’ll be lower in antioxidants and polyphenols. Olive oil can be composed of refined olive oils, extra virgin or virgin olive oils and it is often light in colour and taste. The refining process allows the oils to be used at high temperatures but also strips it of its healthy amino acids and nutrients.

There’s a long-standing debate surrounding the suitability of olive oil when it comes to cooking. The argument against cooking with olive oil – particularly extra virgin olive oil – is that it has a low smoke point; this is the point at which the nutrients and phytochemicals in the oil start to burn, thus removing their flavour and health properties and giving a nasty bitter edge to the oil.

Extra virgin olive oil has a lower smoke point than most other oils (somewhere in the range of 170–180ºC). Generally speaking, the more flavourful your oil is, the lower the smoke point will be, as it is the flavour particles that burn once the oil is heated.

The idea that you can’t sauté or fry in extra virgin olive oil, though, is totally wrong. 160–180ºC is an ideal temperature for frying most things, and most extra virgin olive oils will not degrade at this temperature; instead, they give your food a wonderful richness of flavour. If you’re looking to sear something over very high heat, use a refined oil with a very high smoke point like sunflower or pomace oil – for everything else, we use extra virgin olive oil.

So, how do you choose a good quality extra virgin olive oil that works for you? There is no replacement for tasting – the flavour spectrum of olive oils is huge and the only way to find the one variety you like is by trying a whole load of different styles. When it comes to picking a good oil, however, it pays to know about some of the jargon that surrounds it. Olive oil is a little like wine in that sense: there are some things you can look out for that will give you a better idea of exactly what you are buying.

Top of the list is the bottle itself. Extra virgin olive oil has many enemies – heat, air and light being chief among them. No self-respecting bottle of olive oil would come in a transparent container – look out for oil that comes in opaque tins or darkened bottles, as this is a good sign that the producer understands the importance of blocking out light.

If you are looking at two extra virgin olive oils that seem similar but there is a wide price discrepancy, there are lots of factors that might be relevant. Where the olives were grown, when they were harvested (early harvest for extra virgin olive oil is important), what types of olives were used, where the bottle was produced, how the olives were picked (mechanically or by hand) – these are all things that have a huge impact on the cost of your olive oil. If you’re looking for something balanced, don’t be afraid to turn to extra virgin olive oil blends that retain all the fantastic health and flavour properties of olive oil, but also combine different varieties to create something with a well-rounded, versatile flavour profile. Carapelli, for example, takes great care selecting the best extra virgin olive oils from different geographical regions, combining them in unique blends to suit different palates and uses. Where many olive oils can vary from year to year and bottle to bottle, Carapelli’s blends are consistent in terms of flavour and quality.

Once you’ve found the olive oil that works for you, treat it like you would any flavoured oil. You wouldn’t cook with sesame oil unless it had a purpose in the dish, and good olive oil has just as strong a flavour, so why treat it any differently? In making her pumpkin frittata, Giulia Scarpaleggia gently fries garlic in extra virgin olive oil to infuse the flavours – a common technique in Italian cooking. She sweats an onion in extra virgin olive oil to make her farro and borlotti bean soup before finishing the dish with more oil for flavour. The reason in both cases is because the flavour of the oil is an essential part of the dish. Extra virgin olive oil has a remarkably versatile taste: it goes beautifully with meat, fish, bread and pasta, but also with sweet flavours like vanilla, chocolate and fresh fruit. Next time you’re cooking and you feel like something is missing, try adding a splash of extra virgin olive oil – it might just take your dish to the next level.