I love olive oil.
When in Greece, I always start a meal in a restaurant with a hunk of fresh bread dipped in a little pool of olive oil sprinkled it with a bit of salt and pepper. Nom.
In my own kitchen in Greece, I almost exclusively use olive oil. Yes, even when frying. In fact, most restaurants and home cooks in Greece use only olive oil and celebrate it:
The Olive Tastes Network of Crete promotes the healthy, tasty, and cultural value of olive oil through certification of restaurants that only use olive oil in all of their cooking.
However, there seems to be a lot of controversy about using olive oil for high-heat cooking (searing, sautéing, stir-frying, and deep-frying) and much of the chatter, such as here and here, says that using olive oil for high-heat cooking is bad:
- “DANGER: Don’t Cook with Olive Oil!”
- ”… the wonderful benefits of olive oil are completely destroyed when you heat it.”
- “[Cooking in olive oil in high heat] causes enzymes to be destroyed, proteins denatured, carbohydrates (sugars) caramelized, vitamins and minerals less available, and water eliminated.”
- “..the process of heating oils can cause the fats to become carcinogenic; which means causes CANCER!”
- “Frying with olive oil releases TOXINS!”
Well, heating food does destroy enzymes, denature proteins, caramelize sugars and reduce water content, but that is irrelevant because olive oil itself doesn’t have much – if any – of these. As for the foods themselves, we want some of these things to happen to make our food tastier and easier to eat and digest.
And “toxins?” My skeptic radar goes on high alert when this favorite of the “woo-woo” cult (along with “chemicals”) get mentioned. Many foods contain substances that are toxic (for example: alcohol, apples and carrots), and cooking can produce more. However, there’s no need to panic at the thought of eating a little bit of something that, in large amounts, could poison us. Our bodies are quite used to dealing it.
So let’s look at some of the claims made against high-heat cooking with olive oil.
The smoking point of olive oil is too low for frying.
“Smoking point” is the moment when a heated oil begins to smoke continuously, at which point its fat molecules start to break down. Heated past its smoking point, the fat also releases free radicals and a substance called acrolein, the chemical that gives burnt foods their bitter flavor and smell, and your kitchen a smoky, scorched odor.
Some cooking oils and fats get to their smoking point before reaching a good high-heat cooking temperature.
However, smoking oil isn’t always a bad thing – sometimes you want your pan blazing hot. But you still need to be careful to add your food immediately so that the oil doesn’t keep smoking.
Although recipes may vary, when frying you usually want to preheat your oil to somewhere between 325°F and 375°F degrees. During cooking, you should keep it between 250°F and 325°F degrees. Keeping your oil hot enough, but not too hot, will make sure your food is crispy, golden, and never soggy.
Frying temperatures will change olive oil from a ‘good’ fat to a ‘bad’ fat & destroy its healthy properties.
Cooking fats and oils are either saturated, trans or unsaturated. The first two are less healthy, but unsaturated fat, including olive oil, is more healthy. Trans fats are created when oil is hydrogenated, which means making it solid at room temperature, like margarine. The hydrogenation process is complex, and involves heating oil under extreme pressure and then bubbling hydrogen gas through it. You cannot make this happen in your kitchen. The heat needed to raise the temperature of olive oil high enough to fry food simply cannot change the chemical composition from ‘good’ to ‘bad’.
As well, a study reported in the Journal of Agricultural and Food Chemistry tested the effects of continuously heating virgin olive oil for 36 hours to measure how the oil deteriorated. It didn’t. The scientists reported that despite the continued heating the oil kept most of its nutritional properties.
You cannot reuse olive oil.
All cooking oils (including olive oil) will eventually oxidize and get rancid if they are repeatedly used at high temperatures: each time oil is heated and cooled it will lose some of its fragrance, flavor, freshness and health-giving polyphenols.
But studies have shown that olive oil is more resistant to oxidation than other cooking oils. Also, it is unlikely that you’d use the oil more than once for either pan or deep frying since pieces of fried food usually stay in the used oil, even after filtering. I will reuse my oil when frying “bland” food such as potatoes, but only use it once when frying fish or meat because I don’t want to share the flavor: French fries that taste like yesterday’s calamari aren’t great.
Olive Oil is Too Expensive.
In the rural Mediterranean, olive oil is a staple product: most families own olive trees and harvest them every year. In Greece, we buy our olive oil from friends 20 liters at a time, and since it is local and avoids middleman markups it is relatively inexpensive.
Admittedly, outside the Mediterranean, good, “real” olive oil is more expensive than other options. When in North America I use either a cheaper, more refined olive oil when I pan fry or deep fry, or I will use canola oil, which is a healthy alternative to olive oil in high-heat cooking.
So assuming you are already eating a balanced and nutritional diet, there is no reason not to fry with olive oil.
Olive oil: Use it, taste it, enjoy it.
What about you. Do you fry with olive oil? If not, why and what do you use instead? Let us know in the comments below.
Want to learn more about olive oil, including great ways to cook with it? Try these recommendations:
Attya M, Benabdelkamel H, Perri E, et al. Effects of conventional heating on the stability of major olive oil phenolic compounds by tandem mass spectrometry and isotope dilution assay. Molecules. 2010 Dec 1;15(12):8734-46.
Cicerale S, Conlan XA, Barnett NW, et al. Influence of heat on biological activity and concentration of oleocanthal–a natural anti-inflammatory agent in virgin olive oil. J Agric Food Chem 2009;57:1326-30.
Why Food Browns. http://www.scienceofcooking.com/maillard_reaction.htm (Accessed April 3, 2016)
News on the FDA Ban on Trans Fats and Alternatives http://missjones.co/blog/fda-ban-on-trans-fats-and-alternatives-for-frosting (Accessed April 12, 2016).
Naturally Occurring Food Toxins http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3153292/ (Accessed April 1, 2016)