Drying characteristics and quality of taegeuk ginseng (Panax ginseng C.A. Meyer) using far-infrared rays

摘要

The purpose of this study is to investigate the drying characteristics of taegeuk ginseng using a far-infrared dryer. The dryer used for this experiment can control the drying parameters such as far-infrared heater temperature and air velocity. The far-infrared drying tests of taegeuk ginseng were performed using large, medium and small ginseng at an air velocity of 0.6 m s~(-1), and drying chamber temperatures of 45, 55 and 65 ℃. The results were compared with those of the hot-air drying method. The drying characteristics were analysed based on factors such as drying rate, colour changes, internal tissue structure of ginseng, saponin contents and antioxidant activities, and energy consumption. In general, the hot-air drying time was 3-3.5 days longer than that of far-infrared drying under the same conditions. The colour changes of far-infrared drying were also smaller than that of hot-air drying. Far-infrared dryer required less energy consumption about 9.67-14.8% less than that required by hot-air drying. At the same time, the saponin and polyphenol contents of taegeuk ginseng subjected to far-infrared drying were 1.01 mg g~(-1), 7.81 mg/100 g higher than that subjected to hot-air drying, respectively. The results showed that the far-infrared drying increases the capacity and quality of taegeuk ginseng.