Bioaccessibility and antioxidant activity of phenolic compounds in cooked pulses

Summary The aim of this study was to evaluate the bioaccessibility of polyphenols and antioxidant activity in cooked pulses and to study the effect of cooking on their total phenolic content (TPC) and antioxidant capacity. Cooked faba beans showed the highest TPC, followed by soybeans and lentils or peas. TPC ranged from 10.4 ± 0.2 to 52.9 ± 0.3 mg/100 g and was positively correlated with antioxidant activity. Cooking resulted in increased TPC and antioxidant activity of the methanolic extracts, caused by cell disruption and improved extraction of polyphenols. Although polyphenols were lost in the cooking water, boiled legumes had more polyphenols than those resulting cooking broths. In vitro gastrointestinal digestion resulted in increased TPC and antioxidant capacity of the extracts. Soybeans showed the highest amount of bioaccessible polyphenols. The release of phenolics from cooked legumes was mainly achieved during the intestinal phase. Literature data may underestimate the TPC and antioxidant capacity of pulses. This study evaluated the bioaccessibility of polyphenols and antioxidant capacity in eight different pulses as well as the effect of boiling on their total phenolic content and antioxidant capacity. Overall, boiling increased the amount of polyphenols and the antioxidant capacity of the methanolic extracts. Boiling water contained significant quantities of polyphenols, although boiled legumes contained more polyphenols than their resulting cooking broths. Proteins should be removed prior to determination of phenolic content in protein‐rich foods such as legumes and their cooking broths.