Physicochemical Qualities and Physiological Activities of Black Soybeans by Cultivation Area and Cultivars

Abstract

This study determined the effects of the area under cultivation and cultivars, on the quality and physiological activities of black soybeans. The crude contents of ash, fat and protein were determined to be 5.96∼6.62%, 12.22∼18.52%, and 40.06∼43.08%, respectively. Lightness of both cultivars were high in samples cultivated in Milyang. Although significant differences were obtained in redness and yellowness between cultivars, no differences were observed with respect to the cultivation area. The total dietary fiber content ranged from 20.56 to 36.49%, with Socheongja in Milyang and Cheongja in Suwon having the highest dietary fiber content. The phytic acid content ranged from 1.76 to 2.1%, with highest content obtained in the Socheongja cultivar of the Suwon cultivation sample. FRAP values were also found to be higher in the Socheongja samples of the Suwon cultivation (32.33 µM) as compared to Socheongja obtained from Milyang cultivation (5.67 µM). The α-glucosidase inhibitory activity was determined to be twice as high in Socheongja as compared to Cheongja, with no difference observed by region of cultivation. Thus, our study indicates that depending on the cultivation area, functional components and physiological activities for the same cultivar are different.