Hot extrusion 3D printing technologies based on starchy food: A review

Three-dimensional (3D) printing is a new technique used to construct complex geometric forms for personalized nutrition and customization. With good rheological and gelling properties, starch materials have great potential in the 3D printed food industry. The successful printing of materials depends on various aspects, and current researches have focused on discussing the influence of the rheological properties of starch materials on printing, while the researches on the printing characteristics with other starch properties, material processing methods, printing process parameters are still insufficient. This review mainly focuses on the relationship between the material properties of starch foods and hot extrusion 3D printing, discussing the influence of material properties (rheology, adhesiveness, thermal properties, microstructure and component interaction) on the feasibility of printing. In addition, the effects of additives (hydrocolloids, lipids, fiber, protein, salt and other), processing methods, and process parameters (nozzle diameter, print height, print speed, and throughput) on printing are reviewed.