Thickeners could be used to 3D print food.  In their paper, they discuss a method for direct ink writing (DIW) 3D printing of soybean dregs (a soybean byproduct from soy milk and tofu production) without the use of rheological modifiers.  The paper was published recently in the American Chemical Society-Food Science and Technology. 

To achieve the desired "ink" properties of the food, the researchers reused the discarded bean residue.  Their tests showed that particle size was an important variable in determining the rheological properties of the "ink".  They characterized different formulations of bean residue "ink" and analyzed its rheological properties and structural properties.  The results show that the particle size is a basic variable to determine the rheological characteristics of soybean residue ink.  The research team demonstrated the 3D-printable bean residue ink with a bean residue powder of 33% by weight and a particle size of  

Making the most of these underused nutritious foods will promote the sustainability of food supply and reduce food waste, the authors said.  The researchers plan to develop more "inks" made from other food residues to promote sustainable food development.