Effect of different cooking conditions on phenolic compounds and antioxidant capacity of some selected Brazilian bean (Phaseolus vulgaris L.) cultivars

The effects of different cooking conditions such as soaking, atmospheric (100 °C) or pressure boiling (121 °C), and draining of cooking water following thermal treatment on phenolic compounds and the DPPH radical scavenging capacity from two selected Brazilian bean cuitivars (black and yellow-brown seed coat color) were investigated using a factorial design (2 ³). Factors that significantly reduced the total phenolic contents and antioxidant capacity in both cuitivars were the soaking and draining stage. Independent of cooking temperature, total phenolics and antioxidant capacities were enhanced in treatments without soaking and where cooking water was not discarded, and this was likely linked to an increase of specific phenolic compounds detected by high performance liquid chromatography such as flavonols and free phenolic acids In both cuitivars. Cooking of beans either at 100 or 121 °C, without a soaking stage and keeping the cooking water, would be recommendable for retaining antioxidant phenolic compounds.