Biological Effects of Frying Oils Mediated by the Activation of Peroxisome Proliferator-Activated Receptors (PPAR)
In recent years the contribution of frying oils to total dietary energy intake has markedly increased in industrialized countries
Biological Effects of Frying Oils Mediated by the Activation of Peroxisome Proliferator-Activated Receptors (PPAR)
In recent years the contribution of frying oils to total dietary energy intake has markedly increased in industrialized countries. This is mainly due to the rising consumption of deep-fried products, which are very popular because of their desirable flavor, color, and crispy texture.
Deep-frying is a process of immersing food in hot oil, which acts as a heat transfer medium and contributes to the texture and flavor of the fried food. During deep-frying several chemical reactions occur within the frying oil, including the thermal oxidation of unsaturated fatty acids (FA). In the course of thermal FA oxidation a heterogeneous mixture of chemically distinct substances is formed including hydroperoxy and hydroxy FA such as 13-hydroperoxyoctadecadienoic acid (13-HPODE), 9-hydroxy- and 13-hydroxyoctadecadienoic acid (9-HODE, 13-HODE) as well as cyclic FA monomers (CFAM). Large quantities of the frying oil containing these substances are absorbed into the fried food during deep-frying, and, therefore, ingested during their consumption. For instance, the fat contents of potato crisps, doughnuts, and French fries are 35-40%, 20-25%, and 10-15%, respectively. B