粒径对铁皮石斛粉多糖释放及其粉体特性影响OA北大核心CSTPCD

In order to clarify the effect of particle size on the dissolution rate of polysaccharides and the characteristics of Dendrobium officinale powders,eight D.officinale powders with different particle sizes were prepared through coarse grinding.and ball milling.Changes of the specific surface area,polysaccharide dissolution rate,powder flowability,hydration characteristics,surface microstructure,and color difference were investigated.Results indicated that the dissolution rate of the polysaccharide increased with the decrease of particle size in the range of[20,200)mesh.However,a reduction of dissolution rate was observed when the particle size over 200 mesh.The flowability parameters of D.officinale powder,including the angle of repose,angle of slide and Carr's index,were negatively correlated with particle size.This indicated that the flowability of powder was getting worse with the decrease of particle sizes,especially for powders with a particle size range of[200,250)mesh compared to that of[150,200)mesh.The water holding capacity,water stable aggregates and water solubility index increased initially and then decreased as the particle size decreased,which reached a turning point at 200 mesh.The color difference analysis showed that the parameters,including L*,a*,b* and ΔE,also exhibited the largest variation between the[150,200)mesh and[200,250)mesh powders.The reason could be due to the considerable increase in the specific surface area of the[200,250)mesh D.officinale powder compared to the[150,200)mesh(68.1%).In conclusion,the D.officinale powder with a mesh size of[150,200)(d50=95.6 µm)demonstrated favorable powder characteristics,release rate of polysaccharides and a fine particle size.This study provided a theoretical basis for the improvement of grinding process and the enhanced utilization of D.officinale.