Effect of amorphization method on the physicochemical properties of amorphous sucrose

Our objective was to characterize the physicochemical properties of amorphous sucrose prepared by freeze-drying (FreD), spray-drying (SprayD), ball milling (BallM), melt-quenching (MeltQ), and spin-melt-quenching (SpinMeltQ). Scanning electron microscopy indicated that FreD, SprayD, BallM, and SpinMeltQ formed distinct particles, while MeltQ formed a single mass. Powder X-ray diffraction confirmed that BallM was semi-crystalline, while FreD, SprayD, MeltQ, and SpinMeltQ were amorphous. However, total scattering pair distribution function analysis of synchrotron X-ray diffraction data suggested that local molecular-level ordering differences existed between MeltQ and FreD, SprayD, and SpinMeltQ. Chromatographic analyses revealed that thermal decomposition indicator compounds were present in BallM, MeltQ, and SpinMeltQ, but not in FreD and SprayD. All samples exhibited a glass transition. Additionally, FreD, SprayD, BallM, and SpinMeltQ exhibited an exothermic cold crystallization peak, but MeltQ did not. Overall, this research provides evidence that sucrose is a material whose physicochemical properties are strongly influenced by amorphization method.