In addition to being high in monounsaturated fats, bioactive compounds and vitamins, extra virgin olive oil can reduce the loss of nutrients from foods during cooking. This shows a review of more than 90 scientific papers by researcher José Fernando Rinaldi de Alvarenga, a FAPESP fellow and postdoctoral researcher at the Food Research Center (FoRC), a FAPESP Research, Innovation and Diffusion Center (CEPID) based in the faculty in Pharmaceutical Sciences from the University of São Paulo (USP).
The research was carried out in collaboration with colleagues from the University of Barcelona, Spain and published in an article in the scientific journal Trends in Food Science and Technology.
“Before any explanation, it is important to deny once and for all that cooking with this oil is not healthy,” Alvarenga told the FoRC communications office. It used to be thought that fatty acids in extra virgin olive oil would oxidize at higher temperatures. “This is due to olive oil’s smoke point, where oils begin to burn, smoke and oxidize. Although its smoke point is lower than other oils, we now know that the smoke does not come from these fatty acids, but from minor components of olive oil. Extra virgin olive oil ‘stands’ higher temperatures than other oils.”
He explains that monounsaturated fats predominate in extra virgin olive oil, which have antioxidant potential, among other benefits. “Because of this effect, the breakdown of olive oil is slower compared to other oils. And that protects both the nutrients in the oil itself and those in the food.”
One example is the bioactive compounds in food, which have multiple health-promoting properties. “Extra virgin olive oil helps prevent phytochemicals from oxidizing. This makes cooked food healthier by preserving important components that might otherwise be lost. For example, comparing a tomato stew with and without oil, the amount of lycopene can be reduced without the presence of oil in the cooking process. However, by using extra virgin olive oil, we managed to preserve this compound, which is associated with the prevention of prostate cancer,” comments the postdoc.
influence of cooking
However, the study shows that the breakdown of bioactive compounds varies depending on the cooking method. Several studies have been analyzed on nutrient loss in foods cooked in the oven, pan, sautéed, broiled, or sautéed using a Spanish technique called stew, which is similar to the preparation of a moqueca, or pot meat.
“We have seen that cooking in an oven is the technique that promotes the greatest degradation, as it involves very high temperatures and a very long cooking time,” explains Alvarenga.
Degrees of degradation also vary depending on the bioactive compound. For water-insoluble compounds like carotenoids and fat-soluble vitamins, cooking and steaming are the techniques that best preserve these compounds. On the other hand, they are lost significantly in microwave ovens and fryers.
According to the researcher, it is important to emphasize that there is no contraindicated method. “But in general, if the goal is to get the most out of the nutrients from plant-based foods and olive oil, it’s preferable to use techniques with shorter cooking times and milder temperatures.”
manufacturing
For Alvarenga, extra virgin olive oil brings benefits because it doesn’t go through the same industrialization processes as the most popular oils in Brazil, such as sunflower, soybean and corn oil. “The Mediterranean diet is considered one of the healthiest in the world, mainly because of the olive oil. One of the reasons for this is that most oils are extracted directly from olives. That means they don’t go through a refining process,” he explains. “Extra virgin olive oil processing does not involve heating, just physical processes like cold pressing, centrifugation and filtration that preserve these compounds.”
There are oils made from different olives, with Arbequina, Picual and Hojiblanca being among the most common. However, it was observed in the study that this has little impact after cooking, as does the amount of bioactive compounds in the final product. “What needs to be taken into account is not the olive variety but its growing conditions. That is, climate, temperature and rainfall. Then there are the conditions of extraction, processing and storage,” emphasizes the researcher.
Revista Galileu