Extra virgin olive oil

One of the topics that came up at the Support Group on Sunday (and I cannot remember what prompted it!), was the use of extra virgin olive oil (EVOO) for cooking. One of the ladies there, who I think may have some sort of medical or science background, said that EVOO should never be used for cooking purposes. She said this was because when it is heated it turns into a saturated fat. Now, I use EVOO all the time for cooking and have done for a number of years - so this was not only news to me, it was also a little alarming. So, I've looked it into a little on the Internet (click on the link above for one web site with some more information).

Now, I don't understand all the chemistry behind this (and there's a lot!) so I'll keep it as simple as my own brain can cope with! Basically, EVOO is an unrefined variety of olive oil - meaning that it has only been pressed from the original olives once. EVOO has very little saturated fat in and a high level of monounsaturated fats - from a healthy eating perspective, both these things are very good, and this makes it one of the best, healthiest oils to use with food. However, the unrefined nature of this oil also makes it one of the most fragile, both chemically and nutritonally. This means that when heated, it is more likely to alter, chemically-speaking, than other more refined oils.

Oils have what is known as a smoke point - the temperature at which the oil starts to vapourise. Because of its relatiely fragile nature, EVOO has a lower smoke point than most other oils. At its smoke point, EVOO (and other oils) may (a) produce saturated fats, (b) lose nutritional value, and (c) develop carcinogenic (cancer-forming) compounds. Now, the advice I have seen on the Internet is rather variable. Some web sites (mainly those trying to flog EVOO), seem to be saying it's fine to cook with EVOO - and it's just a myth that it develops saturated fats etc. These sites seem to suggest that for any damaging effects to occur from cooking with EVOO, you would have to cook at very high temperatures - such as those used in commercial cooking (e.g. deep fat frying where there is also repeated heating of the oil). They suggest temperatures up to about 400 deg F might be OK. However, there are other web sites that advise caution and suggest that EVOO is 'at risk' at temperatures as low as 200 deg F - temperatures much more likely to be encountered during normal domestic cooking. They suggest EVOO should only be used for 'cold' uses such as salads and dressings. Some say it's OK to use for 'normal' home cooking purposes such as making sauces - but not for the sort of temperatures that might be used in baking.

My fairly rapid Internet research clearly does not reveal any definitive answer - so, the choice is yours. Personally, I think I will cautiously finish off the bottle of EVOO I am currently using and from then on, use olive oil, rather than the extra virgin variety (everyone seems to be agreed that this is OK and has a much higher smoke point).