Particle morphology development during spray drying is critical to powder properties. The aim of this study was to investigate whether the dextrose equivalence (DE) of maltodextrins can be used as an indicator for the final particle morphology. Maltodextrins were characterized on glass transition temperature (T_g) and viscosity, where low DE-value maltodextrins exhibited higher T_g and viscosity than high DE maltodextrins (≥21). A new custom-built sessile single droplet dryer was used to analyse morphology development of minute maltodextrin droplets (R₀∼100 μm) at 60°C and 90°C. Droplets with low DE showed early skin formation (2-5s) and developed smoothly shaped particles with large cavities. Rheology on low DE maltodextrin films at dry matter of 82% (w/w) suggested that drying droplets acquired elasticity after locking providing resistance against surface compression. After locking morphology development is probably halted as the glassy state is approached. On the contrary, rheology on high DE maltodextrin (≥21) films at dry matter of 93% (w/w) suggested that drying droplets with high DE developed viscous skins, which are susceptible to surface deformations, leading to wrinkling, folding or creasing particle morphologies. The results demonstrated that DE-value may be used as an indicator for particle morphology development when interpreted in view of the process conditions.

喷雾干燥过程中形成的颗粒形态对粉末性能至关重要。这项研究的目的是研究麦芽糖糊精的右旋糖当量（DE）是否可以用作最终颗粒形态的指标。麦芽糊精通过玻璃化转变温度（T _g）和粘度进行表征，其中低DE值的麦芽糊精比高DE麦芽糊精（≥21）表现出更高的T _g和粘度。使用新的定制无柄单液滴干燥机分析麦芽糊精微小液滴的形态发展（R ₀约100μm）在60°C和90°C下。具有低DE的液滴显示出早期的皮肤形成（2-5s），并形成了具有大空腔的平滑形状的颗粒。低DE麦芽糖糊精膜在干物质为82％（w / w）时的流变学表明，干燥液滴在锁定后获得了弹性，从而提供了抗表面压缩的能力。锁定后，随着接近玻璃态，形态发展可能会停止。相反，高DE麦芽糖糊精（≥21）膜在干物质为93％（w / w）时的流变学表明，高DE的干燥液滴形成了粘稠的皮肤，易于表面变形，导致起皱，折叠或起皱粒子形态。结果表明，当根据工艺条件进行解释时，DE值可以用作颗粒形态发展的指标。