While there are several drying processes available for food, the spray drying process is distinguished by its unique equipment that allows for rapid drying with minimal heat exposure. In spray drying, a liquid is sprayed through an atomizer into a chamber that contains streams of hot air. The moisture quickly evaporates, leaving behind solid powder particles that fall to the bottom of the chamber.
Spray drying is ideal for heat-sensitive materials and whenever a free-flowing, uniform powder is required. Whereas other drying techniques typically produce flakes that then must be ground to size, spray dryers create a free-flowing powder with a narrow size distribution, making a subsequent grinding step unnecessary. Furthermore, spray drying is considered the method of choice for commercial-scale encapsulation applications and is used to encapsulate flavors, carotenoids, and lipids.