Flavor encapsulation capacities of amphiphilic polyvinylpyrrolidone as a carrier for amorphous solid dispersions

This study investigates the characteristics of amorphous solid dispersions (ASDs) formed using an amphiphilic carrier polymer, focusing on the effects of source solution conditions on flavor retention. Cinnamaldehyde and polyvinylpyrrolidone (PVP) were dissolved as flavor and carrier components in methanol or ethanol under different conditions and subsequently spray-dried into fine powders. The amount of cinnamaldehyde retained in the spray-dried ASDs was quantified to assess the impact of solution conditions. The results indicate that cinnamaldehyde molecules were physically entrapped within the entangled PVP chains during the spray-drying process. The flavor encapsulation capacity of PVP reached a maximum of approximately 4 mmol/g-PVP under specific conditions. This maximum capacity implies that each cinnamaldehyde molecule is associated with approximately two PVP monomer units, which is higher than those reported for selected cyclodextrin-based systems in comparable contexts of cinnamaldehyde encapsulation. Additionally, the dissipation of cinnamaldehyde from the ASD samples during storage under vacuum was examined.