The vegetables, kale and red cabbage , were purchased in the Municipal Market of Santos (São Paulo, Brazil). Sampling was conducted in three batches of each variety. Each batch was composed of three packets of kale or three units of red cabbage, which were later, divided into laboratory samples. The vegetables were washed, dried with paper towels and manually chopped as similarly as possible to the typical domestic preparation of these vegetables. To make the samples more homogeneous, eliminate the factor sample moisture and minimize experimental error, the three batches of each vegetable were homogenized, and then the samples for each analysis were weighted, 15 g of kale and 50 g of red cabbage. One portion was retained as a raw sample, and the others were cooked in triplicate using three different techniques, as described below. The adequate amounts of samples were only weighted previously to the cooking processes. In other words, samples were not weighted after cooking and, therefore, the raw sample weight was always considered as basis comparison for all the calculations. Subsequently, the samples were stored at 20ºc in tightly closed packages.