The nutritional powders are extremely perishable and yet, for a number of reasons, it has to be preserved for later consumption. The removal of water prevents the growth of microorganisms and facilitates preservation and storage of milk constituents. Spray drying is one of the most convenient techniques for producing dietary powders and for stabilizing nutrients.
Spray drying is the process of converting a mixture in its liquid form to a powder. This is done by removing the moisture component from the liquid solution. The solution, sometimes called an emulsion, is sprayed through a nozzle into a chamber that simultaneously has hot air being blown into it. As droplets of the solution are released through the nozzle and come in contact with the hot air, the moisture content of each droplet is removed, thus turning it from liquid to powder form.
Uniform and controlled sized particles are formed.
The heat and mass transfer ratio is larger for particles; thereby it provides excellent solubility of the powders.
Spray drying is better as compared to other methods of drying such as, ovens, freeze dryers, etc. The other methods produce irregular shaped and sized particles with low solubility index.
Spray Drying gives fresh taste to the product even at the end of the shelf life of the product.
Increases shelf life of powders.
Spray dried products can be easily packaged and transported.