Here’s why supermarket extra virgin olive oils are a bad idea

Here’s why I think supermarket olive oils are almost always a bad idea. There’s a certain exception to this rule, and we’ll get to that, but first let’s talk about why they’re better avoided.

Firstly, the choice. You might think there are so many options from so many different countries and who really cares about olive oil anyway? But the reality is these oils are quite often pretty similar in terms of quality, most supermarkets (and consumers) care mainly about 2 things—the taste and the price. If this sounds like you then that’s fine, but there is a lot more to olive oil than just that. More on that later.

The storage conditions are also not great. A lot of supermarket oils can sit for a long period of time in warehouses waiting to be transported to the shelves. Freshness is very important for olive oils, not only for taste but also for the polyphenols (the part that makes olive oils healthy). Oil that sits in the bottle for months before landing on your table is definitely not ideal. You can mitigate some of these effects by buying a higher quality oil with more polyphenols. This way when they naturally degrade over time there will still be plenty left over available to do their work. The other factor is how exposed the oil is to sunlight when it is in the warehouse, being transported, or sitting on the supermarket shelf. If oil is exposed to the UV in sunlight, it will degrade quicker.

Since most supermarkets have to keep a close eye on price, the best olive oil producers do not get the shelf space in the UK, so the best quality oils are actually found online. The UK is not well known for its olive oil, or even olive oil consumption, so the oils from the more premium producers would get overlooked. One really important factor when looking at olive oils is how forthcoming the producer is with the oil’s analysis results. Here’s an example: https://tenutecristiano.com/the-oils/ - look at the quality of the analysis done by Tenute Cristiano. They prominently show important metrics of the oil like acidity (lower is better) and polyphenols (higher is better). This producer is imported into the UK from Italy by Just Gourmet Foods, and only available in the higher end UK supermarkets like Ocado.

The exception to this general rule however, is extra virgin olive oil for frying (always buy extra virgin by the way, it’s better quality than other types). Although you can fry with EVOO (extra virgin olive oil), it’s high smoking point of 210 degrees Celsius, but it’s best to be careful in how you do it. Ideally you would fry on a low to medium heat and for as short a time as possible. This will protect some of the more fragile components in the oil and keep it in its most nourishing state. I find a good balance is to have a higher quality EVOO that is solely to be added raw as a dressing to food, this way the healthy benefits are maximised. Then, I may have a lower quality supermarket oil on hand to fry with. I personally go for an organic, unfiltered EVOO, as unfiltered oils have a higher polyphenol content than if they were filtered. Important note: For your better quality high polyphenol oil - go for filtered as it will last much longer.