Edible Films from the Laboratory to Industry: A Review of the Different Production Methods

Edible films or coatings as potential replacements for traditional plastic food packaging are a popular subject for research. This article provides a narrative summary of the progress of research into edible food packaging and preparation methods at three different production scales over the past 5 years. First, at the laboratory research level, commonly used coating methods include dipping, vacuum dipping, and spraying. Films are mostly made by solution casting, while 3D printing film technology and electrospinning/electrostatic spraying are emerging technologies in the field. At the pilot level, panning coating, brush coating, and fluidized bed technologies give edible food packaging a more scalable and realistic approach. On an industrial manufacturing scale, in order to improve film formation efficiency, blowing, injection, calendering, etc. are generally based on the extrusion mode. Laboratory-scale research is critical for developing materials and exploring their properties. The technology used for industrial-scale production needs to consider factors such as cost and efficiency. Each technology for making food packaging needs to be selected according to the production purposes and the currently available packaging equipment. However, commonly used edible packaging source materials are generally derived from biological macromolecules such as proteins and polysaccharides. These materials are heated and extruded in industrial production, and their performance will be inferior to that of traditional plastic packaging. In addition, high cost is also a factor that must be considered.