3D food printing of alternative proteins: materials, processes and challenges

The increasing global demand for sustainable protein sources, driven by environmental concerns, population growth and evolving dietary preferences, has positioned alternative proteins as a critical area of food research. Concurrently, three-dimensional (3D) food printing (3DFP) has emerged as a transformative technology offering unprecedented customization, structural complexity, and innovative product development capabilities. This review comprehensively examines the synergistic potential of 3DFP in enhancing the production, sensory appeal and nutritional value of alternative proteins, including plant-based, algae-based and insect-based proteins. This review critically analyzes the unique material properties and printability characteristics of these protein types, with particular emphasis on rheological behavior, yield stress and viscoelastic profiles, alongside an analysis of applicable 3DFP techniques, including extrusion-based, inkjet, selective laser sintering and binder jetting. The article highlights successful applications, compares 3DFP and traditional protein production methods, and critically assesses the prevailing technical, scalability, regulatory and consumer acceptance challenges. The article emphasizes printing parameters across protein types for method selection for specific formulations. Future directions show the integration of artificial intelligence, smart ink development, and multi-technology platforms to advance industrial-scale production of 3D-printed alternative proteins.