Thin-Layer Drying Rates and Quality of Cultivated American Ginseng

GINSENG roots harvested in May, July and September 1986 (74 to 83% w.b. moisture content) were investigated to determine the effect of drying temperature, airflow rate and the diameter of the roots on drying rates and quality. It was found that drying air ternperature had the greatest effect on drying rates and ginseng quality, particularly below moisture contents of 28 to 30% w.b. (moisture ratio of 0.1). The diameter of the roots had some effect on drying rates and quality. Airflow rate and initial moisture content (harvest date) had little effect on drying rates. The thin-layer drying daia collected for these samples fit Page's Equation (1949) well. The drying parameters K and N were generalized as functions of drying air temperature (T) in C and the root diameter (D) in mm.