Drizzling extra virgin olive oil on grilled/steamed vegetables or fish, pouring extra virgin olive oil on rustic bread or sliced tomatoes … Well, I think this may not be the most common ways most of us in Asia prepare our dishes and the typical food we consume.
During our planning for our new venture in the olive oil business, we asked the very first question to ourselves: Given all the health benefits, can we also use extra virgin olive oil for everyday cooking and frying?
Here is what we have found!
Normal Cooking Temperature: In a study conducted by Dr. Nurhan Dunford (Ph. D., Oil/Oilseed Chemist) of the Oklahoma State University, it was found that the normal temperature range for food service frying is between 160°C and 190°C. Most foods cook rapidly in this temperature range and develop a golden colour, crisp texture, and good flavour.
In The Joy of Cooking, one of the world’s most widely read cookbooks written by Irma Rombauer, recommends frying at 185ºC for best results.
Olive oil is ideal for frying. In proper temperature conditions, without over-heating, it undergoes no substantial structural change and keeps its nutritional value better than other oils. — Frying with Olive Oil from the International Olive Oil Council.
As a reference, the following table shows the standard cooking temperatures for various types of food from the International Olive Oil Council:
TYPE OF FOOD
|Medium (130–145º C)||
High water content: vegetables, potatoes, fruit…
|Hot (155– 170º C)||
Coated in batter,flour or breadcrumbs, forming a crust
|Very hot (175–190º C)||
Small, quickly fried: small fish, croquettes
Two Considering Factors When Frying With Cooking Oils
- Smoke Point
- Oxidative Stability of the Oil
A smoke point is defined as the oil begins to smoke and starts to form unhealthy compounds when heated over its tolerable limit. The oil becomes not healthy, in fact, is harmful to our health. It is a standard measure of cooking oil’s thermal stability when heated in contact with air.
The Science of Cooking with Olive Oil written by Dr. Mary Flynn (PhD, RD, Associate Professor of Clinical Medicine at Brown University’s Alpert Medical School) and the Australian Olive Association both confirm that Extra Virgin Olive Oil can be heated up to 215°C or 420°F before it reaches the smoke point.
Smoke Point of Extra Virgin Olive Oil
The smoke point of Extra Virgin Olive Oil ranges from 190ºC to 215°C depending on the quality of the EVOO. This smoke point is higher than the normal frying temperature as suggested by the experts.
High quality extra virgin olive oil has a higher smoke point than mass produced ones. The quality of extra virgin olive oil is determined by the low free fatty acids. The lower the free fatty acid it has, its oxidative stability is better, and in turn the smoke point is higher.
Factors which lead to a high free fatty acidity in extra virgin olive oil include bruised or damaged olives, fruit fly infestation, fungal diseases in the fruit, and delays between harvesting and extraction.
Oxidative Stability & Smoke Point
The oxidative stability also depends on the reaction rates of the unsaturated fatty acids (monounsaturated and polyunsaturated fat) with oxygen.
Olive oil is one of the most stable cooking oil in this respect because it has a high percentage (75%) of monounsaturated fat (oleic acid) which has one double bond and hence less susceptible to oxidation as compared with cooking oils that has high polyunsaturated fats, where there are many double bonds.
The double bonds are unstable when heated and they tend to react with oxygen. Saturated fats have zero double bonds and hence very resistant to high heat.
Heat Stability: Antioxidants & Vitamin E Help Fight Oxidation
Extra Virgin Olive Oil is an unrefined/unprocessed oil cold pressed from the olive fruits. The process does not involve heat, chemical, or water in the extraction of oil from the olives. In the West, they call this oil, olive juice.
The cold pressed oil extraction method retains most, if not all, of the phytonutrients, specifically, polyphenols and oleocanthals, as well as its Vitamin E, which are antioxidants that protect the oil from damage during high heat cooking.
When heated, olive oil is the most stable fat, which means it stands up well to high frying temperatures. Its high smoke point (210ºC or 410ºF) is substantially higher than the ideal temperature for frying food (180ºC or 356ºF). — From International Olive Oil Council.
In many studies conducted for domestic frying, it was discovered that extra virgin olive oil was highly resistant to oxidation, heat-stable, and did not form significant amounts of harmful compounds at the end of the lab studies, whereas vegetable oils like sunflower oil did oxidise and form harmful compounds.
These studies were conducted at extreme conditions, namely, under high heat and for a long period of time. Therefore, as consumers, we should not be overly alarmed by the results because under home cooking situation, we are unlikely subject our cooking in such extreme conditions.
In home cooking, we normally do not heat the oil up to the highest temperature range as would in the food services, and we also do not cook for a long period of time. Moreover, in batch frying, the temperature drops 30 to 40°C when product is added to the fryer. The temperature drops can be higher for frozen food.
Weight Control: Why Not Using Extra Virgin Olive Oil for Everyday Cooking & Frying?
When we fry our food within the recommended frying temperature, that is below 180°C, it normally absorbs 8 to 25% oil.
By using olive oil for frying, it forms a crust on the surface of the food that impedes the penetration of oil. And hence food fried in olive oil has a lower fat content than food fried in other oils, making olive oil more suitable for weight control.
How does Olive Oil Compare with Other Cooking Oils?
The table below shows the smoke point of a few other cooking oils. Keep in mind that the smoke point for a vegetable oil will vary according to the variety and growing conditions, and how the oil was produced (unrefined, refined, semi-refined, or super refined).
|TYPE OF OIL
|| SMOKE POINT (TEMPERATURE)
|Sunflower Oil (refined)||227ºC|
|Grapeseed Oil (refined)||216-220ºC|
|Canola Oil (refined)||204ºC|
|Extra Virgin Olive Oil (unrefined)||190-210ºC|
Tips for Cooking With Olive Oil
Although extra virgin olive oil stands up to heat remarkably well, they do lose flavour as they are heated.
Extra virgin olive oil is best used to balance the acidity in high-acid foods, such as tomatoes, harmonise the spices in a dish, enhance the flavours of the dish, and to add body and depth.
In general, we need to carefully pair the olive tastes with the flavours of the other ingredients in the dishes we are creating.
Different frying method requires different kind of cooking oil.
Extra virgin olive oil is suitable for lite temperature frying at a temperature below 180°C.
The bottom line is stir frying vegetables with extra virgin olive oil and fresh garlic at medium heat without burning them seems like a healthy and tasty approach.
We recommend using extra virgin olive oil as cooking oil to cook vegetable or drizzle it over grilled or steamed vegetables to reap the most health benefits offered in both extra virgin olive oil and vegetables.
For deep frying (190°C-200°C), it is advisable to use other cooking oils that have higher smoke point, such as pure olive oil and extra light olive oil. The table below shows other types of cooking oils that are meant for deep frying, sorted in descending order of smoke point.
|TYPE OF OIL
|| SMOKE POINT (TEMPERATURE)
|Rice Bran Oil||254ºC|
|Pure/Extra Light Olive Oil (refined)||242ºC|
|Olive Pomace Oil (refined)||238ºC|
|Vegetable Oil (Palm Olein & Soybean) (super refined)||235ºC|
|Sunflower Oil (refined)||227ºC|
|Grapeseed Oil (refined)||216-220ºC|
Extra virgin olive oil has been used for frying all types of food for centuries. Whenever we cook with extra virgin olive oil, do remember to raise the frying temperature gradually, and never heat up the oil at high heat.
Taking Things in Perspectives
Extra virgin olive oil is part of the Mediterranean diet and Mediterranean diet has been shown over the centuries good to our health.
The Mediterranean Diet is rich in vegetables, fruit, peas and beans, and grains. There is little red meat and most fat is unsaturated and comes from extra virgin olive oil in culinary preparation. Having a small amount of red wine has been shown to increase the health benefits, in combination with moderate exercise and not smoking.
Photo: Audrey Low. Flickr.com. Creative Common License.
Moderation is key!
Whether we are pan-frying, stir-frying or sautéing, there is one thing in common: the food we are preparing is subjected to a cooking temperature around 180°C.
High-heat cooking, whether we are using olive oil or not, will have already destroyed some, if not all, of the nutrients in the food we use. Even worst, overheating may produce unwanted and harmful compounds in our dishes.
However, two things are for sure:
- Extra Virgin Olive Oil is a healthy cooking oil.
- It can be used for low to medium temperature frying not exceeding 190°C.
We have switched to using extra virgin olive oil for many years now.
We tend to think that consuming extra virgin olive oil is definitely healthier than other cooking oils for a very simple logic.
Just imagine if you are like us like to add lots of chili oil in every meal we take. Will it be better off if the cooking oil used to prepare the chili oil is extra virgin olive oil?
We are consuming “olive juice” instead of a refined vegetable or seed oil which has undergone high heat, and chemical refining, such as using Hexane, which is a hydrocarbon chemical made from crude oil, during the extraction process.
We would feel safe in consuming the “olive juice” in the chili oil. — Agus Rahardja & Shirley Shih.
Extra Virgin Olive Oil is a Healthy “Olive Juice”
How much Extra Virgin Olive Oil could contribute to our health is a question that we would not be able to answer. However, we believe that every single little things we do count towards prevention. Prevention is better than having to experience the emotional struggle when things happen.
Start giving our kids and family the best that we could so that they would have a healthier and heartier future. Little things count. Consistency helps. Persistency would pay off.
Start it early and start them young. It would not be too late for grown up adult to start living a healthy lifestyle too.
Let’s have a peaceful mind once and for all!
All oils have smoke point, the temperature at which smokes are seen. If you have overheated an oil way pass its smoke point, please discard the oil and start over again.
Extra virgin oil is best used for uncooked dishes or dishes that are cooked at low to medium temperatures. Pure or extra light olive oil (refined) is the choice for high-heat cooking for temperature exceeding 190°C.