Researchers at the University of the Basque Country (UPV / EHU) have found food for the first time in the presence of certain aldehydes suspected of being behind neurodegenerative diseases and some types of cancer . These compounds are toxic in some oil when heated to the frying temperature.
As explained the study’s authors to the agency SINC, the study confirms the simultaneous presence in the frying oil of various toxic aldehydes in the group of oxygenated α, β unsaturated, such as 4-hydroxy-[E]-2nonenal. In addition, two of them are described first in foods (4-oxo-[E]-2-ten and 4-oxo-[E]-2-undecenal). So far these substances have only been cited in biomedical studies, where does your existence in the body with various types of cancer and neurodegenerative diseases like Alzheimer’s and Parkinson’s.
Toxic aldehydes generated as a consequence of the degradation of oil fatty acids, and although some are volatile, others remain therein after frying. Thus, if the oil is reused, it can be incorporated into the cooked food. Because they are highly reactive compounds can react with proteins, hormones and enzymes in the body and prevent proper operation.
The experiment, published in the journal Food Chemistry, consisted of heating at 190 ° C in an industrial fryer three types of oil: olive, sunflower and flax. The operation was performed for 40 hours (8 hours) in the first two and 20 hours for the case of linseed oil. The latter is not commonly used for cooking in the West, but was chosen for its high content of omega-3 groups. The results show that sunflower and flax oils, especially the first-, are generating more of toxic aldehydes and in less time. On the contrary, olive oil , which has higher concentration of monounsaturated acids (as oleic), generates less and later these harmful compounds.