This might be an idea you're already familiar with, but sometimes those fancy bottles of olive oil just call to me from their supermarket shelf, begging to be purchased. If you're splurging this holiday season, be sure to know how NOT to use them!
Sometimes, when you feel like splurging for a holiday dinner or a special occasion, it's tempting to buy the best oil you can find. However, as Harold McGee writes in The New York Times, using a pricey oil, or even a mid range variety, may make absolutely no difference in the taste of your food.
He tested 15 oils, 4 of them olive oil, and determined the following:
"We were surprised at how thoroughly heat obliterated the flavors in cooking oil until they all tasted more or less the same. Even prize-winning, and costly, extra-virgin olive oils lost much of what makes them special, though they retain their apparently healthful pungency. To get food with the green and fruity flavor of good olive oil, it seems more economical and effective to fry with an inexpensive refined oil and drizzle on a little fresh olive oil after cooking."
Some specialty oils like sesame and peanut will retain their flavor when heated, but most conventional oils - olive, canola, vegetable - will not.
And don't forget that oil does go bad. Try to buy in small quantities and be aware of any off odors or tastes. Save the expensive and flavored specialty oils for a last minute drizzle or to serve with a crusty fresh baguette, and stock up on the cheap stuff!
• Read more: Is It Time for an Oil Change in the Kitchen? at The New York Times
Related: Supermarket Saver: How Much to Pay for Olive Oil?
(Image: Flickr user WordRidden licensed for use under Creative Commons)
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I'm surprised the article didn't mention the distinctive fishy smell that canola oil gives off when heated. I would never use it for cooking.
I've found much the same thing in my own kitchen-I can tell the difference between cooked olive and vegetable oil (and have since switched to using olive oil in all cooking) but can rarely tell the difference between olive oils once cooked (I think the exception is olive oil cake). As long as the oil tastes pleasant enough raw, its good for cooking. Save the really tasty expensive stuff for salad.
I read the article yesterday on the NY Times site and found it confusing. McGee kind of skimmed over the smoke point issue, which I think is of greater significance than the issue of pricey vs. inexpensive olive oils.
For any high-heat cooking, we an use oil with a high smoke point, like avocado oil. We would never use sesame or olive oils at very high heat.
The UC Davis study said over half the imported olive oil claiming to be extra virgin was either oxidized or adulterated.
http://olivecenter.ucdavis.edu/news-events/news/files/olive%20oil%20final%20071410%20.pdf
He focused on flavor, but in my experience with oil, I chose more about it's smoke point than anything. I use peanut oil because of how hot I can get it for frying, if need be.
With the price of olive oil compared to various other "frying" oils, it seems weirdly gluttonous to me to think of deep frying in the stuff!
also, isn't it actually bad to cook in high temperatures using olive oil? i usually just use it for light sauteing, and of course vinaigrettes. i cook using grape seed oil or organic canola oil which i have found doesn't have a fishy smell. for indian food, on the other hand, i cook with virgin organic coconut oil and love the way it augments the flavour of the food.
@heather77 - I agree. Also, I would have liked McGee to go into more detail about how the oil changed the taste of food - if there were noticable flavors present in food cooked in oil that may have not be identifiable by tasting the oil alone.
@Sian - Yes, I always notice a flavor difference when cooking pancakes with olive oil instead of vegetable oil, for example. I think the key is to not be swayed by olive oil marketing when it comes to buying oil for cooking or frying versus using it in a way you can actually taste its flavor.
@the polish chick - I've heard it's bad to cook at high temperatures using any oil, especially if it's heated to smoking point. I tend to use olive oil for cooking, but I very rarely fry or deep fry.
I've been using grapeseed oil for a lot of my cooking, on a friend's recommendation, because it has a higher smoke point than olive oil. I don't notice a difference in flavor, but I love not worrying about my kitchen filling with smoke when I brown pork chops.