The polyphenol content of your oils will change when you cook with them. This is a known fact explored through many scientific studies. Polyphenols are natural antioxidant compounds in extra virgin olive oil, such as Hydroxytyrosol and Oleuropein. They contribute to the oil’s bitterness, stability, and many of its health-related properties.

What we need to understand however is how they change and how we can best deliver these high impact polyphenols into our diet.

The most important factor is the temperature used for cooking.

If you are cooking up to 180C / 356F

– The loss is moderate and gradual

– If you are sautéing or baking therefore, the loss is not a major concern and the oil remains stable because the antioxidants protect it

– With high polyphenol oils, there is also a transfer of the polyphenols to the ingredient you are cooking, so there is a secondary benefit

If you are cooking at a higher heat of around 200C / 392F and above

– Polyphenol losses become more significant

– The longer the exposure at high temperatures, the greater the reduction of polyphenols

– But oils with high polyphenol levels retain them better (auto-protecting themselves). You should avoid using lower quality olive oils at higher temperatures

What all of this means is that you very much should be using Extra Virgin Olive Oil to cook with, but that you should aim to cook at moderate temperatures. Of course, if you use your oils raw, they have the highest polyphenol content, but this doesn’t just mean you can use them to dress a salad. You can and should put a swirl of great olive oil on all your cooked food as well. It raises the overall nutritional content by a mile as well as enhancing the flavour of each ingredient.