Optimization of Spray-drying Process for Liange Xiaoke Extract Based on the Multi-index Comprehensive Scoring Method

OBJECTIVE To optimize spray drying conditions of Liange Xiaoke extract by multi-index comprehensive score method. METHODS With spray powder flour yield, moisture content, content of puerarin and berberine as indexes, factors affecting spray drying were investigated by single factor test. With composite score of flour yield, moisture content, content of puerarin and berberine hydrochloride, orthogonal test was used to optimize spray-drying process with feeding speed, inlet air temperature, the amount of adjuvant and relative density of extract as factors.RESULTS The flour yield, moisture content, content of puerarin and berberine in Liange Xiaoke extract was directly influenced by feeding speed, inlet air temperature, the amount of adjuvant and relative density. Among these four process parameters, the inlet air temperature and feeding speed had significant effects. The optimal conditions were determined as follows:inlet air temperature 160℃, relative density of extract 1.07 g·mL^-1, feeding speed 7.5 mL·min^-1, and the amount of adjuvant 5%. CONCLUSION The optimized spary-drying process is stable, reasonable and feasible, it can be used as reference for industrial production.