Pretreatment Technologies for Feedstock in Melt Extrusion-Based Food Additive Manufacturing: Advances and...

Although additive manufacturing (AM) has found widespread applications in the food industry, there are still very few food materials that can be directly printed, resulting in a scarcity of finished printed products available on the market. To broaden the applications of food AM, it is essential to pre-treat food materials to enhance their physicochemical, nutritional, and flavor properties. This review comprehensively examines the existing literature on technologies related to the preparation of feedstock for AM, highlighting advances in food pre-treatment technologies within this field. It also proposes unresolved issues and outlines future research prospects. The development of pre-treatment technologies for food AM signifies a broader integration of AM within the food industry. The materials used in food AM must possess suitable rheological properties to ensure smooth extrusion from the nozzle, as well as adequate mechanical properties to maintain the shape fidelity of the printed products. We summarize innovative treatment techniques, including novel physical field treatments, enzymatic methods, and chemical treatments, while explaining the underlying mechanisms involved. The future trajectory of 3D food products is geared towards commercialization, necessitating more advanced pre-treatment techniques to meet evolving market demands.