Additive manufacturing of food

3D printing of food can be used to shape a food item—such as a purée—into a specific form created in a digital file. It also provides an opportunity to place flavors or ingredients within a 3D geometry. At RISE, 3D food printing has been used to design foods that are easier to swallow, as well as to prototype foods with reduced salt content.

The video shows a texturised food for dysphagia "timbale" being 3D printed into a broccoli floret.

Additive manufacturing, or 3D printing, is a production technique where a digital file is first created for the design. Since a digital file can be easily modified, it is a perfect tool for exploring different geometries and creating prototypes. The tool is well-suited for conducting initial tests in product development, and also for placing different flavors and ingredients within a 3D geometry.

At RISE, 3D printing has been used to shape products for patients with dysphagia, or swallowing difficulties. To facilitate swallowing for this patient group, food is puréed and then mixed with starch and egg, which is baked in the oven into what is known as a timbale. Timbales can be shaped by cutting them or by molding them in a form. In research projects at RISE, the timbale mixture has been 3D printed to more closely resemble the original food it is made from. This is intended to increase interest in the food among a patient group that is often affected by malnutrition. The video below shows an example of a broccoli floret being 3D printed from broccoli purée.

The material, such a purée, to be 3D printed is filled into a steel container, and to build up the structure, the purée is extruded onto the build plate or plate according to the digital file. For the structure to be successfully created, the flow properties of the ingredient are crucial—the viscosity must allow it to flow out of the nozzle at a suitable rate as the structure is built. The material deposited on the build plate must also be able to hold its shape, which requires characterization of the ingredient’s viscoelasticity and yield stress. In one publication, we explored the rheological properties of 3D-printed timbales, where we aimed to increase the fiber content in the formulation.: https://www.frontiersin.org/journals/food-science-and-technology/articles/10.3389/frfst.2022.1058641/full