[Optimization for vacuum belt drying process of Qibai Pingfei granule through response surface methodology]

Based on single factor tests,the optimum vacuum belt drying conditions of Qibai Pingfei granule were obtained through Box-Benhnken central combination design and RSM. In this study, drying time, drying temperature and extract density were chosen as independent variables, while transferring rate ginsenoside Rg₁, Re, Rb₁and astragaloside IV were taken as dependent variables. The optimum parameters are as follows: drying time of 112 min, drying temperature of 87 °C and extract density of 1.30 g · mL⁻¹. At the optimum condition, transferring rate ginsenoside Rg₁+ Re, Rb₁and astragaloside IV were 88.01%, 87.31%, 84. 34%. Above all, the optimum processing parameters of vacuum belt drying of Qibai Pingfei granule is reasonable and feasible, which can provide reliable basis for production.