Micro/nano-encapsulated phase change materials (PCMs) as emerging materials for the food industry

Background: The development of energy saving methods and energy storage materials is an emerging hot topic in various fields including the food industry. Thermal energy storage can be accomplished through formulation and application of phase change materials (PCMs). Micro/nanoencapsulation of PCMs is an efficient method for increasing their thermal conductivity, barricades their feasible interaction with the surrounding matrix, and leaks during the melting operation, which lead to an increase in the thermal efficiency of the system. Scope and approach: In this study, we have tried to present a comprehensive review on types and properties of PCMs, encapsulation techniques of micro/nano PCMs, and applications of PCMs in the food industry and future outlook. Key findings and conclusions: Application of thermal energy storage through formulation and use of PCMs is a feasible solution for storage/release of energy. In order to apply PCMs more efficiently, it is necessary to encapsulate them before their application in the final process/product such as incorporating PCMs into packaging structures and refrigeration equipment because of the solid-liquid phase changes. Moreover, micro/nanoencapsulation methods of PCMs are classified into three categories; i.e., chemical (such as suspension polymerization, emulsion polymerization, mini-emulsion polymerization, in Situ polymerization, interfacial polymerization, etc.), physicochemical (such as coacervation, sol-gel encapsulation, etc.), and physicomechanical (such as spray drying, electrohydrodynamic processes, etc.) techniques. Also, the PCMs-assisted packaging is an innovative field of interest for energy storage/release systems to adequately coat or control temperature sensitive food products in various conditions, and could be applied in smart food packaging or pharmaceutical packaging.