Objective:To optimize the spray drying process for extracted, purified and concentrated liquid of Sophoraflavescens. Methods:The process was optimized by L9 (34) orthogonal design, the evaluated factors included the extract specific gravity,the inlet air temperature and the pump speed, and the weight of extract powder and the content of matrine/oxymatrine were used as the evaluation indices. Results :The optimal spray drying process was as follows:the extract specific gravity of 1.07, the air inlet temperature of 120℃ and the pump speed ...