Change of Proximate Composition, Antioxidant Activity, and Ginsenoside Content of White Ginseng with Different Roasting Conditions

Abstract

Background: The purpose of this study was to evaluate roasting conditions to optimize the physicochemical properties of ginseng to improve its utilization as a food material.BRMethods and Results: Roasting was performed at different temperatures (140, 160, 180, and 200℃) and times (10, 20, and 30 min). The total phenolic content of ginseng powder was greatly between 160℃ for 20 and 200℃ for 10 min achieving a 7-fold increase (22.92 mg·gallic acid equivalents/g) compared to that of the control. As the roasting temperature and time were increased, the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activities of ginseng powder were significantly increased. The total ginsenoside content was decreased with increasing treatment time at a roasting temperature of 180℃ - 200℃. The maximum total ginsenoside content (9.25 mg/g) was obtained at 180℃ for 10 min, however, there was no significant difference compared to that of the control. The panaxatriol Rh1 content was increased as the roasting level was increased. Overall, this study demonstrated physicochemical changes in 4-year-old ginseng roots according to the roasting conditions.BRConclusions: We suggest the optimal roasting conditions of 160℃ for 30 min or 180℃ for 10 min to minimize the reduction in total ginsenosides, yield, and proximate composition and maximize the polyphenol content and antioxidant activity.