Recent progress in the stickiness reduction of sugar-rich foods during spray drying

Spray drying of sugar-rich foods causes problems, related mainly to low glass transition temperature, which is manifested by high stickiness, lower drying efficiency, and yield. Thus, a number of research papers have been published recently on this topic. This study summarizes the obtained results and indicates possible future directions. The most popular method to overcome the stickiness problem is still the application of carriers. However, in addition to conventional carriers like maltodextrin and gum Arabic, novel carriers are also being tested. The carriers with additional health-promoting properties are the most interesting group. In the material-science approach the application of proteins as anti-stickiness agents can also be mentioned. Moreover, the raw materials can be modified by membrane techniques to reduce sugar content and increase glass transition temperature. In the process-based approach, the main efforts are mostly focused on decreasing of drying temperature. Currently, the use of dehumidified air has been successfully verified as a possible way to reduce drying temperature. The reduction of stickiness achieved by this method allows to minimize the amounts of carriers added into the feed before spray drying.