ABSTRACT
Encapsulation is used to protect sensitive materials from adverse environmental conditions and control their release during transportation, storage, and consumption. It is applied in various industrial sectors, such as food, nutraceutical, and pharmaceutical industries. Nowadays, the use of drying methods for encapsulation is of growing interest, and freeze drying is commonly applied for various heat-sensitive ingredients. In this chapter, the general principles, process parameters, types, and applications of freeze drying are described and analyzed. The need for drying methods for encapsulation, as well as the specific principles and applications of freeze drying encapsulation, are also discussed, following a comprehensive review of the available literature. The important advantages of this method are the use of low temperatures that allows for the encapsulation of sensitive ingredients, the preservation of biological activity of the dried products, and the production of particles in the micro- and nanoscale leading to high encapsulation efficiency and increased stability. Finally, microwave freeze drying is also described as a promising encapsulation method to reduce the operation cost and increase the process rate.
