Dietary fiber and total phenolic content of selected raw and cooked beans and its combinations

Beans are distinctive among a diverse and broad class of legumes. Certain health products claimed their products are high in dietary fibers and total phenolic content (TPC) because they applied bean combinations. This study aimed to determine the dietary fibers and TPC of raw and cooked beans and its combinations. Individual beans studied were kidney bean, mung bean and chickpea. Bean combinations were done by mixing each of the homogenized beans flour in the ratio of 1:1 (w/w) and 1:1:1 (w/w/w). Dietary fibers were determined using enzymatic-gravimetrical method whereas TPC was determined spectrophotometrically. Results showed the insoluble dietary fiber (IDF), soluble dietary fiber (SDF), total dietary fiber (TDF) and TPC for individual raw beans varied from 20.52 to 26.61 g/100 g, 1.20 to 2.45 g/100 g, 22.08 to 27.81 g/100 g and 0.48 to 1.04 mg GAE/g, respectively. For raw bean combinations, the IDF, SDF, TDF and TPC varied from 20.74 to 23.96 g/100 g, 2.3 to 2.50 g/100 g, 23.05 to 26.46 g/100 g and 0.80 to 0.85 mg GAE/g, respectively. No significant different (p > 0.05) in IDF and SDF for raw bean combinations and individual raw beans. Meanwhile, certain raw bean combinations contained significant higher (p < 0.05) TDF and TPC than individual raw beans. The IDF, SDF, TDF and TPC for individual cooked beans varied from 14.49 to 26.30 g/100 g, 1.40 to 2.02 g/100 g, 15.88 to 28.31 g/100 g and 0.57 to 1.20 mg GAE/g, respectively. For cooked bean combinations, the IDF, SDF, TDF and TPC varied from 15.73 to 23.03 g/100 g, 1.73 to 2.36 g/100 g, 17.46 to 24.95 g/100 g and 0.61 to 1.08 mg GAE/g, respectively. After cooking, the IDF, SDF, TDF and TPC of certain beans combinations were significantly higher (p < 0.05) than individual beans. This study supports the proposal that bean combinations can possibly be used as a method to increase the amount of dietary fibers and TPC.