Changes in Physicochemical Characteristics and Antioxidant Activity of Adzuki Bean and Adzuki Bean Tea Depending on the Variety and Roasting Time

摘要

This study investigated the changes in physicochemical characteristics of adzuki bean (Vigna angularis van nipponensis) tea depending on the variety and roasting times, for the development of functional foods. The levels of total polyphenol, flavonoids, and tannin contents were 12.72 mg gallic acid equivalent (GAE)/g, 3.01 mg catechin equivalent (CE)/g, and 3.56 mg tannic acid equivalent (TAE)/g, respectively, for the Jeolgangsung-ipat sample roasted for 16 min. The highest DPPH (l,l-diphenyl-2-picrylhydrazyl) radical scavenging activity was 7.81 mg Trolox equivalent (TE)/g in Bulgeun-ipat sample that was roasted for 14 min. The highest total polyphenol content in the hot water-leached liqueur of adzuki bean tea was 26.55 pg GAE/lOOmL in Yungum-patthat was roasted for 12 min. The total flavonoids and tannin contents of Whin-ipat and Jeolgangsung-ipat roasted for 10 min were 15.10 pg CE/100mL and 14.60 pg TAE/100mL, respectively. The highest DPPH and ABTS (2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid) radical scavenging activities of hot water-leached liqueur of adzuki bean tea were 488.72 and 728.25 mg TE/100 mL, respectively, in Yungum-pat roasted that was for 12 min. The results of this study show that roasted adzuki bean tea has notable antioxidant activity and is considered to have significant health benefits.