Which granulation process uses a sufficient volume of hot air to evaporate and dry liquid droplets and can be used in encapsulation?

• A. Spray Congealing
• B. Spray Drying
• C. Spray Chilling
• D. Two of the Above

Answer: (B)

Using a sufficient volume of hot air to evaporate and dry liquid droplets is characteristic of spray drying. In this process, a liquid feed—often containing an encapsulating material—is atomized into fine droplets and introduced into a chamber with heated air. The moisture rapidly evaporates as the droplets travel through the hot stream, leaving behind dry particles that are collected as a powder. This drying mechanism makes it particularly suitable for encapsulation, because as the droplets dry, a protective matrix forms around the core material, effectively trapping it inside a stable shell. Unlike methods that rely mainly on cooling or solidification, spray drying achieves the desired moisture removal through evaporation, enabling efficient production of encapsulated powders.