1 Universidade Federal de São Paulo, Brazil.
A diet rich in fruits and vegetables can be associated with delay of the aging process and a decreased risk of developing chronic diseases, because of their antioxidant powder. The methods used to evaluate the antioxidant capacity can be classified according to the mechanism of deactivation of reactive species, which is based on electron transfer (ET) or hydrogen atom transfer (HAT). Many chemical in vitro methods are commonly used, however, the cellular antioxidant capacity assay consider the absorption, distribution and metabolism of the antioxidant compounds in cellular level. The antioxidant compounds are susceptible to losses, so in relation to vegetables that are usually consumed after having been submitted to some cooking process, it is still important to consider the way to prepare them. Thus, the aim of this work was to investigate the effects of different home cooking techniques (boiling, steaming, and stir-frying) on kale and red cabbage, evaluating the antioxidant capacity by the methods of ABTS (ET-based assay), ORAC (HAT-based assay) and the cellular antioxidant capacity assay (CAC). The ABTS assay was conduced applying ABTS radicals, while in the ORAC and CAC assays were used the peroxyl radicals. In relation to the kale, the steaming technique implied in significant increases on antioxidant capacity levels, in all the evaluated methods (186.9%).