As a continuing study on the chemical evaluation of the utility of the farinfrared drying method for crude drugs, the efficiency in the drying process of Zingiberis Rhizoma was examined in comparison with the conventional drying methods such as an air drying and a hot-air drying. Furthermore, the chemical fluctuation of the constituents during the drying process has been investigated by means of HPLC quantitative analyses for pungent principles and galanolactone, and GLC quantitative analyses for bisabolane-type sesquiterpenes. It has been found that, by use of the far-infrared drying method (oven temperature 60°C), the rhizome of Zingiber officinale was dried efficiently without reducing the contents of bioactive constituents.
