Use

tomato & picuda

Extra Virgin Olive Oil for everyday Cooking

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:

TEMPERATURE
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

  1. Smoke Point
  2. 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
Lard (unrefined) 180-205ºC
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: Flickr.com. Creative Common License.

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.

Photo: kattebelletje. Flickr.com. Creative Common License.

Photo: kattebelletje. Flickr.com. Creative Common License.

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!

Health Note:

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.

4 thoughts on “Use

  1. Hi,

    Which olive oil in your product range would u suggest to use to make a simple but nice aglio olio spaghetti?

    Thank you very much.

    Best regards
    JUPE

    • Hi JUPE. Thanks for asking. Here is our thought.

      Our suggestion is to use Mueloliva Clásica.

      Clásica is a delicate and mild extra virgin olive oil, and it goes very well with toasted garlic in the preparation of the Aglio Olio spaghetti, as we do not want the garlic flavour nor the olive oil taste overpowering the other – we want to savour both flavour and taste.

      Interesting video recipe showing the steps to prepare the Aglio Olio spaghetti, http://foodwishes.blogspot.sg/2010/12/this-spaghetti-aglio-e-olio-recipe.html

      Just two notes: the first one is, remember to pour the olive oil in a cold pan first before we heat up the pan.

      Second note is, each individual has his/her own preference of taste – It is what he/she likes that is what matters. So, experiment with different intensity of extra virgin olive oil to see what kind of texture and taste your family members like best.

      Hope this helps.

      Best Regards,

      Agus.

  2. I bought a bottle of Mueloliva Picuda at Duke Bakery @ Liang Court. The bottle has been in the refrigerator for about 1 week but the evoo does not become thicker and cloudy like other brands of evoo which I tried previously. Please help to clarify.

    Thank you and best regards,
    Katherine

    • Hi Katherine, thank you for sharing your observation.

      The purpose of storing olive oil in the fridge is to reduce the rate of oxidation, and hence at best retain or at least not to lose too much of the Polyphenol (antioxidants). However, if we are using our extra virgin olive oil regularly, there is not necessary to store it in the fridge.

      There is one issue in storing extra virgin olive oil in the fridge.

      Once the bottle is opened, and we constantly take the bottle out and into the fridge, the air that is trapped inside the bottle would likely be condensed inside the bottle, and caused degradation of the olive oil.

      Hence premium quality extra virgin olive oil is advisable to be kept in the room temperature in a cool dark place away from light if we are using it on a regular basis, as condensation eventually might affect the “aroma” and “taste” of the olive oil – my own personal experience is: it does.

      The other reason people store extra virgin olive oil in the fridge is because they want to test the authenticity of the extra virgin olive oil.

      The term used is called “fridge test”.

      Fridge test is one of the many misconceptions that we have with extra virgin olive oil – that is, many people believe that authentic extra virgin olive oil, when placed inside a fridge, will become cloudy and solidified.

      Fridge test is not a reliable way to determine whether an extra virgin olive oil is real nor whether its quality is good. Very often, adulterated extra virgin olive oils pass the fridge test.

      Here are the reasons why.

      The solidification of extra virgin olive oil when placed inside a fridge is due to many factors: For the beginning, one is due to (1) the presence of the monounsaturated fat (oleic acid), and the other is (2) the wax content.

      (1) MELTING POINT (Freezing temperature) of Monounsaturated Fat

      According to a chemistry textbook, the melting point (the temperature at which it changes state) of monounsaturated fat is around 13°C.

      However, when the researchers at the University of California at Davis conducted a fridge test with different grades of olive oils and other seed oils at 4°C, high quality extra virgin olive oil only started to show solidification when it was placed in the fridge for five days, but it never fully solidified.

      On a separate experiment, Dr. John Deane put several olive oils in the freezer with a thermometer to determine the actual freezing temperature (melting and freezing points are approximately equal. Small differences between these quantities can be observed.)

      He found that at 4°C, most of the olive oils had not hardened or formed any crystals. At 1.7°C, most were firm enough that they could not be poured but were as soft as butter at room temperature. He observed that as the temperature lowered, more components of the oil solidified. At -12°C, the olive oils were hard enough that a fork could not penetrate them.

      My own experience is this: the temperature of our fridge depends on how empty or full it is at the time of the fridge test is conducted. When the fridge is almost full, the temperature in the fridge may not be as chilled as when it is more empty. As such, the solidification process may take longer to be seen.

      One thing to note: The premise behind this fridge test around the melting point (or freezing temperature) is the assumption that extra virgin olive oil is purely (100%) comprised of monounsaturated fats.

      The fact is: The percentage of monounsaturated fat in extra virgin olive oil varies according to the type of olives used to extract the oil. The range can be from 65 to 80%.

      Hence some authentic extra virgin olive oil needs lower temperature or longer period to be solidified – or be seen thickening and clouding.

      Second note is: Other compounds that are present in the olive oil and the processing method also play a part.

      The processing method such as “winterised”, i.e. chilled and filtered the wax content out of the olive oil, would cause an authentic extra virgin olive oil fail the fridge test, and would only become slightly thick (but not solid) when frozen.

      Finally, in order to achieve and keep a consistent flavour profile, some producers may blend several varieties of extra virgin olive oil. The result of the extra virgin olive oil is commonly called “coupage”. This will also affect the time and the level of cold required to get to the solidification stage.

      (2) WAX CONTENT in Extra Virgin Olive Oil

      The surface of the olive has a coating of a thin naturally produced wax. When olives are extracted into oil, the wax ends up in the oil.

      Different olive varietal produces different amount of wax. The climate, hot or cold, where olives are grown, also play a part – When the weather is hot, more waxes produced than cold.

      While the amount of wax in an olive oil is small, the presence of it is a contributing factor or act as a seed for things to solidify in a cold environment.

      Many adulterated extra virgin olive oil pass the fridge test because it is a blend of extra virgin olive oil and refined olive oil or olive pomace oil. Since refined olive oil and olive pomace oil have a higher wax content, so it solidifies when placed in the fridge.

      For information: The wax content of the extra virgin olive oil, by the International Olive Council’s requirements, should be less than 250 mg/kg. While olive oil is less than 350 mg/kg, and olive pomace oil is more than 350 mg/kg.

      Richard Gawel, an experienced olive oil consultant taster, illustrated with two examples why fridge test is not a reliable mean to determine the quality of the extra virgin olive oil.

      He first put across his point saying that by putting Canola oil, which contains around 50-60% monounsaturated fat, in a fridge, it will solidify to some extent, but Canola oil is not extra virgin olive oil.

      He further illustrated by showing that an adulterated olive oil that contains 90% extra virgin olive oil and 10% Canola oil will still have a high level of monounsaturated fat and will therefore solidify at fridge temperature.

      If fridge test is not a reliable mean to determine the authenticity and quality of an extra virgin olive oil, then what is a better way?

      The colour of the extra virgin olive oil can be enhanced by adding chlorophyll to make it greener. The solidification of olive oil can be easily duplicated by adding more wax content. Adulterated extra virgin olive oil (mixing with cheaper seed oil or olive pomace oil) can be seen solidified in the fridge.

      But it is more difficult to replicate the aroma and taste of a premium quality extra virgin olive oils, which contain “bitterness” and “spiciness” due to the presence of the antioxidants and anti-inflammatory compounds (Polyphenol and Oleocanthal).

      How to select and buy a premium quality extra virgin olive oil? Instead of using fridge test or looking at the colour of the olive oil, we should (1) find out the chemical quality parameters – at least read the Acidity level (Free Fatty Acid) – the lower the better, (2) smell and taste the extra virgin olive oil to detect bitterness & spiciness in it besides the natural fragrance of the extra virgin olive oil.

      IN SUMMARY: All olive oils will eventually solidified in a fridge because of the presence of the monounsaturated fat and the amount of the wax content in it.

      When the fridge is cold enough, the melting point (or freezing temperature) is reached, the olive oil will change its state – from solid to liquid or liquid to solid. It is a matter of time and coldness because our fridge may be more full or more empty.

      For all of our extra virgin olive oils, we can find the chemical quality parameters, including the wax content, at http://buyoliveoil.vas.com.sg.

      For 8 Tips to Choosing & Buying Premium Quality Extra Virgin Olive Oil, we have written an article at http://onlyoliveoil.vas.com.sg/2015/05/8-tips-to-choosing-buying-premium-quality-extra-virgin-olive-oil/

      Hope this explanation helps to clarify.

      Best Regards,

      Agus.

      REFERENCES

      Lab Test by the University of California at Davis: http://dateline.ucdavis.edu/dl_detail.lasso?id=14404

      Report by the University of California at Davis:
      http://olivecenter.ucdavis.edu/research/files/refrigerationisnotreliablefinal.pdf

      Melting Point of Monounsaturated Fat (Oleic Acid): http://www.ncbi.nlm.nih.gov/books/NBK22497/
      http://chemwiki.ucdavis.edu/Biological_Chemistry/Lipids/Fatty_Acids

      The “Home Fridge Test” for Authenticity of Extra Virgin Olive Oil – The Reasons why it doesn’t work by Richard Gawel:
      http://www.aromadictionary.com/EVOO_blog/?p=550

      Myth – the Extra Virgin Olive Oil Fridge Test by North American Olive Oil Association: http://www.aboutoliveoil.org/FridgeTestMyth.pdf

      Cloudy Frozen Olive Oil by Dr. John Deane:
      http://www.oliveoilsource.com/article/cloudy-frozen-olive-oil

      Fridge Test Does Not Reliably Detect Adulterated Extra Virgin Olive Oil by Only Olive Oil:
      https://www.facebook.com/onlyoliveoil/posts/1547673038786561

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