Spray freeze drying - A synergistic drying technology and its applications in the food industry to preserve bioactive compounds

In the food industry, drying is a crucial unit process for extending product shelf life. Many methods are available for drying of foods but spray drying and freeze drying have been widely adopted for industrial drying of a variety of heat-sensitive foods keeping in mind the drying efficiency as well as retention of nutritive components of foods. More recently a novel cutting-edge technique spray freeze drying (SFD) has started evolving in the food sector to accomplish this highly significant unit operation of drying. The advantages of traditional freeze-drying and spray-drying methods are combined in this process. This article explains various spray freeze-drying methods, both new and old, based on a number of factors, particularly the chilling medium and atomization settings. The method with freeze drying and spray drying is then compared, particularly in terms of the morphology and other significant characteristics of the final product obtained. The article also covers how this technology is used in the food sector to preserve bioactive compounds, which serves as confirmation for the comparison made above in terms of data pertaining to the obtained end goods. A brief description is given for its applications in pharmaceutical industry where it first evolved. The technology's scope and potential difficulties have finally been briefly covered. The review was put together using data from roughly ten years' worth of research and analysis in the area of this unique technology.