New Delhi, Jun 30: Researchers from the University of Porto in Portugal have said that any kind of heating reduces the power of the phenolic compounds found in extra virgin olive oil.
So it would be a waste of money, if you cook your food over hear with extra virgin olive oil.
Extra virgin olive oil has more antioxidants than other oils and also contains bioactive components, called phenolic compounds, which are presumed to help ward off cancer and other diseases.
When oils are heated they degrade in quality say the researchers.
Writing in the journal Food Research International, the researchers said, any kind of heating reduced the power of the phenolic compounds in the oil.
They said: ‘Virgin olive oil consumption, as final seasoning or within cooked foods, is increasing worldwide, mainly due to its recognised nutritional benefits.
‘However, different cooking practices, from common frying, to boiling and microwave cooking, undoubtedly modify the olive oil chemical profile.'
Even after being cooked, olive oil will still be at least as healthy as vegetable oil so it is not worth replacing one with the other, said the report.
But it could be ‘economically advantageous' to use standard olive oil rather than pay more for the extra virgin variety, it added.
And there are other ways to get the most out of olive oil when cooking, they added.
One is to keep heating to a minimum, another is to keep adding a splash of olive oil during the cooking process so that it does not get so hot it loses its healthy properties.
The report said: ‘Olive oil performance under prolonged thermal processing is usually equal or superior to other refined vegetable oils.
‘However, as most of its bioactive components, including phenolic compounds, are gradually lost, it is economically advantageous to use lower olive oil grades and frequent replenishment under prolonged thermal processing.
'After a short heating period, most olive oil advantages, in comparison with other vegetable oils, are lost.'