Preparation and Properties of Puerarin Microcapsules

The aim of this study is to optimize the experimental conditions for the preparation of Puerarin microcapsules via the spray-drying using gum arabic and β-cyclodextrinas wall materials. The effects of compound emulsifier ratio, emulsifier concentration, β-cyclodextrin/gum arabic ratio, wall/core ratio and solid concentration on emulsion stability were investigated, as well as the effect of inlet air temperature, feed flow rate and homogenization time on microencapsulation efficiency. The results showed that the maximum encapsulation efficiency of 91.16% was achieved under following condition: composite emulsifier (monoglyceride: sucrose ester=4:6, g/g), emulsifier concentration 1.6%, β-cyclodextrin/gum arabic ratio 5:3 (g/g), wall/core ratio 1:0.15(g/g), solid concentration 15%, inlet temperature 160 ℃, feed flow rate 4 mL/min, homogenization time 6 min. SEM examination showed that the obtained microcapsules were spherical in shape with smooth and continuous surfaces, witha particle size of 15~25 μm. It had a moisture of 2.83%, bulk density of 0.55 g/cm³and angle of repose of 33.60°. Therefore, high-quality microcapsules were obtained under the optimized condition, which had good fluidity and solubility, and can provide reference for the development and utilization of puerarin microcapsules.