Spraydried

Spraydried refers to materials produced by spray drying, a method that converts liquids into dry powders. In this process, a liquid feed is atomized into fine droplets and exposed to hot drying gas, causing rapid solvent evaporation and solid particle formation. The resulting powder is carried from the drying chamber by the gas stream and collected by a cyclone or bag filter, sometimes followed by further milling or agglomeration.

Core equipment and steps include a feed system, an atomizer (such as a spray nozzle or rotary atomizer), a heated drying chamber, and a particle collection system. The atomizer determines droplet size, typically ranging from tens to hundreds of micrometers. The drying gas is usually hot air, though inert gases may be used for heat-sensitive materials. Operating conditions commonly involve inlet air temperatures around 150–300 °C and outlet temperatures around 60–100 °C, with feed rate adjusted to achieve target moisture.

Powders produced by spray drying are typically low in moisture (often 1–5%), highly porous, and flowable. They often exhibit good solubility in water and a broad particle size distribution dependent on process parameters and product requirements. Shelf life is enhanced by reduced water activity when properly packaged and stored.

Applications cover a wide range of industries, including dairy (milk, whey), coffee, egg products, fruit and vegetable powders, flavors, enzymes, and pharmaceutical ingredients. Advantages include rapid drying, protection of heat-sensitive constituents, and improved handling and storage. Limitations include high energy consumption, substantial equipment costs, risks of stickiness for sugar-rich materials, and potential loss of volatile components or flavor if not carefully controlled.

Spray drying remains a common industrial method for producing ready-to-use powders and concentrates across sectors.