Elimination of Heavy Metals(Pb, Cd) by Steaming and Roasting Conditions of Polygonatum odoratum Roots

Response surface methodology(RSM) was applied to monitor the elimination rate of heavy metals(Pb, Cd) and soluble solids depending on the steaming and roasting conditions of Polygonatum odoratum roots. Experiments of 16 different steaming and roasting conditions based on a central composite design for steaming time( min), roasting temperature(), and roasting time( min) were conducted, thereby predicting the steaming and roasting conditions for the maximal responses; soluble solids() at 65.24 min, and 37.58 min; Pb removal rate() at 71.23 min, and 24.35 min; Cd removal rate() at 160.89 min, and 15.81 min, respectively. The optimum conditions estimated by RSM for the maximized values of soluble solids and heavy metal elimination rates were min of steaming time, of roasting temperature, and min of roasting time, respectively. These estimated values were in agreement with those measured by real experiments.