Is Cooking With Infused Olive Oil A Good Thing To Do?

Human research has proven that olive oil, especially Extra Virgin Olive Oil (EVOO), is a better choice than other vegetable oils.

Extra Virgin Olive Oil is a recognized quality source for bioavailable phenolic compound that offers a variety benefits across many diseases like:

Cancer

Cardiovascular Disease
Neurodegenerative Disorders & Other

Olive Oil, a monounsaturated oil, is richer in bioactive chemicals than any other vegetable oils. While it is well known that Olive Oil can be made into an all-purpose healthy oil, maintaining its vast array of nutritional properties below is difficult. Let's take a look at what research has shown about Olive Oil and the various national approaches to it -- deep frying pan, pan-frying, boiling, and roasting.

Deep Frying

The most recent research was published in Food Chemistry 2015 and analyzed the effects of a combination if national cooking techniques within the particular article of Mediterranean foods. This included tomato, pumpkin, potato, eggplant, extra virgin olive oil (EVOO), and tomato. The effects of four different cooking techniques were all examined.

Deep frying (180°C)
Sauteing (80-100degC)
Boiling (plain)
Boiling waterEVOO mixture and both boiling at 100°C

Each subject was allowed to take in ten minutes before being heated up for five minutes.

Surprisingly, analysis revealed that vegetables with extra virgin olive oil (EVOO), were significantly better quality. The oil is infused with phenols from the oil. While this is possible, it is important that we mention that the fat percentage is significantly higher when deep-frying than when boiling is done.

Importantly, you should also remember that different vegetables have different effects. Since the compounds are more concentrated in deep-fried vegetables than at raw vegetables, the overall conclusion is that each vegetable has its own unique phenolic/antioxidant activity profile.

Another study was published in Food Chemistry Toxicology 2010, and specifically examined the effects of Olive Oil frying. Five samples of olive oil, one in particular Extra Virgin Olive Oil from Northeast Portugal, were used for the analysis. The vegetable subject was potato, which was fried in a combination of domestic deep-fat electric fryers at one hundred degrees C. All Olive Oils had the same total phenolic components (TPC), before being fried.

It was revealed that the degradation rates of all olive oils were the same, with a 0.7 per cent increase in an hour at Extra Virgin Olive Oil(EVOO) and 0.8percent in all other olive oils, with no apparent differences. The best oxidative stability was obtained by Extra Virgin Olive Oils (EVOO). After six hours in the frying pan, only the Extra Virgin Olive Oil was left with phenols. All other samples are now reduced.

It is still rare that you cook for 6-12 hours in domestic settings so overall, the analysis determined that olive oil from the commercial type chosen is "clearly resistive to degradation under local frying conditions (one million degC).

A second study published in Journal of Agriculture and Food Chemistry, 2003 found that potato bits were subject to intense frying for 10 min at a hundred and eighty degrees C at Extra Virgin Olive Oil. This analysis revealed that the phenolic chemical concentrations had dropped by 40-50% after only one frying operation, as compared to their original levels. Even after six frying sessions the original concentrations of phenolic chemicals remained significantly lower than 10 percent.

The total antioxidant potential decreased from 740 L of Trolox/kg down less than 250 seconds following the first frying session to 139-144 mg/kg after 12 intervals. Extra Virgin Olive Oil, (EVOO), was very resistant to the formation of polar chemicals as well as total polar material.

Pan-Frying

Pan frying results in marginally faster degradation Extra Virgin Olive Oil (EVOO), than deep frying. According to Food Research International 2013, this may be because of "higher foodoil surface contact, higher vulnerability of atmospheric oxygenand lower temperatures." However, they note that "in comparison to other vegetable oil, fried food is enhanced by olive oil antioxidants as long as it is not extensively heated."

Boiling

A 2010 report in Food Science and Technology used a sample from Extra Virgin Olive Oil (EVOO), Olive Oil, carrots, onions and potatoes to test the effects of peanuts. Vegetables were boiled for 60 second with 60 gram each Olive Oil added at either the beginning or fifteen minutes after the boil.

As expected, boiling does not cause oxidation. All polyphenolic elements and tocopherols were reduced in concentration. However, the addition of olive oil to the boiling process 15 minutes prior to the end of the boil increased "content of oleanolic Acid derivatives, 3,4 DHPEA-EA & 4- HPEA–EA as well as hydroxytyrosol acetate."

Roasting

A 2010 report in Food Chemistry examined the behavior of olive oils phenolic substances during roasting. "Extra-virgin olive oils (EVOO), virgin Olive oil, (VOO), sunflower oil(SFO), peanut oil [PNO], and soy oil (“SO”) were all included in the sample." Beef (150g in a block form) and 150g potatoes (six quarters each). After the vegetables had been boiled, 60 grams of each oil were added to them in an oven at 180 degrees Celsius.

Sunflower and seeds oils had an oxidized appearance and lost their antioxidant potential, in contrast to olive oil which did not oxidize through roasting. This was due to the higher level of tocopherol. Evidently, olive oil and other oils had higher amounts of phenolic substances, which were drastically reduced after roasting. OO samples had a dramatic drop in 3,4 DHPEA EDA (98%) as well as 3,4 DHPEA - EA (70%). However, OO samples showed a greater level of radical activity than other vegetable oil.

Olive Oil's degradation due to processing is complex and depends on many factors. Despite some advantages to heavy fryingpans, the high temperatures of deep-frying cause chemical changes such oxidation, polymerization and hydrolysis.

Olive Oil, in comparison to other vegetable oils is an excellent choice for cooking, regardless of system. It is more resistant to oxidation than other oils and is also far less likely to get damaged by free radicals.

The authors of the 2015 study in Food Chemistry claim that these chemical reactions are affected by the quality and variety of oil, food properties, and the ratio of oil to food.

Olive Oil and Extra Virgin Olive Oil are considered healthy cooking oils, especially when compared with vegetable oils. Reusing oil and reducing cooking time can help reduce oxidation and loss. Olive Oil is best absorbed raw and unprocessed to retain its bioactive components.