Abstract: To optimize spray-drying conditions of compound Platycodon grandiflorums extract.With Spray powder material status,flour yield and moisture content as index, factors affecting spray drying were investigated by single factor test.With composite score of flour yield,content of total saponins of platycodon grandiflorums and moisture content as index,orthogonal test was used to optimize spray-drying process with feeding quantity,inlet air temperature and air flow as factors.The optimal conditions were determined as follows:feeding quantity 25%,inlet air temperature 180 ℃,air flow 700 H/L and relative density 1.07 (25 ℃).The optimized sparydrying process was stable and feasible,it can be used as reference for industrial production.

Key words: Platycodon grandiflorums compound extract, spray drying, flour yield, moisture content, total saponins