Development of aqueous protein/polysaccharide mixture-based inks for 3D printing towards food applications

Three-dimensional (3D) food printing is a promising technique as it allows to create elaborated food constructs or customized food for elderly people and other sensitive population (i.e. children, pregnant women or athletes). The structural and textual properties of food constructs depend strongly on the ingredients used and the shape produced. Two important biological macromolecular components, namely protein and polysaccharides, are the most important in terms of nutritional content. In this work, we developed a water-based protein/polysaccharide food ink from a mixture of gelatin B (GB) and xanthan gum (XG) for 3D printing. A 40-layer 3D scaffold with defined features was successfully printed at room temperature using an aqueous mixture of 3 wt% GB and 10 wt% XG. Adding 37.5 mM calcium ions (Ca2+) or lowering the storage temperature to 4 ℃ improved the rheological properties of the ink, which endowed the scaffold with higher shape fidelity right after printing and good shape retention for at least 96 h. Texture profile results revealed that the infill percentage of the scaffold is critical to textural properties of the scaffold, highlighting the advantage of 3D printing in tuning sensory food perception.