Comparison of Freeze-Drying and Hot-Air Drying on the Appearance, Microscopic Characterization, and Ginsenosides Contents of the American Ginseng

Purpose Our purpose was to compare the difference between hot-air dried American ginseng (HDAG) (Panacis Quinquefolii Radix) and freeze-dried American ginseng (FDAG) (Panacis Quinquefolii Radix) and provide a better drying approach for improving the quality of American ginseng (Panacis Quinquefolii Radix). Methods In our present study, we compared the appearance features of HDAG and FDAG using a CR-410 colorimeter and scanning electron microscopy. Furthermore, we qualitatively and quantitatively determined ginsenosides in HDAG and FDAG by using UPLC-Q Exactive Orbitrap-MS/MS and high-performance liquid chromatography. Results Our present results showed that compared to the hot-air drying method, freeze-drying (FD) has obvious advantages in not only good appearances but also higher bioactive constituents for drying the American ginseng (Panacis Quinquefolii Radix). Conclusion FD is beneficial for the retention of ginsenosides in American ginseng (Panacis Quinquefolii Radix) and also helpful for maintaining the bioactive effects of this functional food.