Cooking vegetables: healthier with extra virgin olive oil

Cooking vegetables with sofrito (saute) with extra virgin olive oil promotes the absorption and release of bioactive compounds from its traditional ingredients (garlic, onion and tomato), according to a study conducted by a research team from the Faculty of Pharmacy and Food Science. at the University of Barcelona (UB), the Center for Biomedical Research on Networking the Pathophysiology of Obesity and Nutrition (CIBERobn) and on Biomedical Research on Diabetes and Related Metabolic Diseases (CIBERDEM) led by Professor Rosa M. Lamuela.

These results, published in the scientific journal molecules, help to better understand the mechanisms with which gastronomy could play an important role in the beneficial effects of the Mediterranean diet on health.

The Mediterranean diet, known for high consumption of phytochemicals derived from vegetables, fruits and legumes, has been correlated with beneficial effects on cardiovascular and metabolic health. This relationship is mainly based on the results of the PREDIMED study, a multicentre clinical trial conducted from 2003 to 2011 with more than 7,000 people and in which Rosa M. Lamuela also participated.

However, the effects on health in the Mediterranean diet have been difficult to replicate in non-Mediterranean populations, probably, according to the researchers, because of differences in cooking practices. As a result, researchers are trying to determine whether Mediterranean gastronomy can have a beneficial effect on health, not only for its foods, but also for the way they are cooked.

Sofrito, a key element of the Mediterranean diet

In this context, the purpose of the study was to evaluate the effect of extra virgin olive oil in the bioactive compounds present in the traditional ingredients of the tomato, onion and garlic in the sofrito, one of the essential cooking techniques of the Mediterranean diet. According to the researchers, this sauce contains forty different phenolic compounds and a large amount of carotenoids. Its consumption is associated with an improvement in the cardiovascular risk parameters and the sensitivity to insulin.

"The main result of the study is that cooking vegetables with extra virgin olive oil promotes bioactive compounds, such as carotenoids and polyphenols found in vegetables that we find in the sofrito, to switch to olive oil, which allows the absorption and bioactivity of these compounds, "said Rosa M. Lamuela, director of the Institute for Research on Nutrition and Food Security (INSA-UB).

Vegetables with olive oil

The study also revealed a new trait of olive oil. Until now, researchers have stated that this oil and onion can produce isomers – molecules with the same molecular formula but with different traits – from carotenoids, more bioavailable variants with higher antioxidant power. . However, the study showed that oil plays a vital role in this process, not only in carotenoids, but also in polyphenols, which range from vegetables to oil.

Anti-inflammatory effects

These results could explain the causes for which previous studies of this research group indicated that the presence of oil increased the anti-inflammatory effect of tomato sauce. "We have seen that this increase could occur due to the migration of bioactive compounds (carotenoids and polyphenols) from tomato to oil during cooking, which promotes the absorption of these compounds," concludes José Fernando Rinaldi de Alvarenga, member of INSA-UB. and first author of the study.

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