Effect of Cooking Conditions on Black Bean Flour Properties and Its Utilization in Donut Cake

Abstract

Utilization of the black bean legume is still limited. The effects of cooking conditions were examined on black bean flour production and the physical, chemical and functional properties of black bean flour were studied. The quality of donut cake made entirely of black bean flour was also investigated. Three cooking methods were investigated: boiling, steaming and pressure cooking. Raw bean flour contained slightly higher protein (29.42 ± 1.03%) and fiber (2.19 ± 0.10%) contents than the flours made of cooked beans. Cooking the beans altered the functional properties of the flour, while the beany flavor was largely eliminated. The hardness of donut cakes increased from 33.32 ± 0.52 to 114.27 ± 10.38 N when raw and cooked bean flour was used, respectively, as did the gumminess (20.08 ± 0.33 to 56.26 ± 2.82) and chewiness (17.86 ± 0.68 to 44.08 ± 4.21). Donut cakes made from black bean flour provided considerable protein (12.31 ± 0.44%) and fiber (1.21 ± 0.01%) contents compared to those produced from wheat flour comprising 7.54 ± 0.12% protein and only 0.03 ± 0.03% fiber. The chemical and functional properties of the black bean flour were not significantly different among the cooking methods. Black bean flour could be used to improve the hardness, gumminess and chewiness of donut cake. Its utilization may be increased through the value adding of protein-rich flour.