As if by magic, the chocolate printer at the OST – Eastern Switzerland University of Applied Sciences creates objects with complicated geometries or seemingly handwritten lettering in its build chamber. Will the chocolate of the future come out of a 3D printer?
The setting is the Institute of Materials Technology and Plastics Processing at the OST – Eastern Switzerland University of Applied Sciences in Rapperswil-Jona, St Gallen. A steady stream of premium dark chocolate flows out of a print head, producing complex three-dimensional shapes and fun lettering. What began as an idea in a 2017 strategy meeting at the institute led to the construction of Chocoformer I, the prototype of today’s 80-kilogram printer, just one year later. “3D printing, referred to as additive manufacturing in technical jargon, is becoming a door-opener for an established traditional Swiss product,” says the deputy director of the institute, Prof. Daniel Schwendemann, with conviction.
Now for a fictional future setting: a souvenir shop in Zermatt. Tourists queue up to have their recently purchased chocolate decorated with a message in their own handwriting or with the Matterhorn. This is made possible by the Chocoformer, along with a design-scanning app developed by computer science students at the OST – Eastern Switzerland University of Applied Sciences: In just a few steps, customers can draw or write something that then gets printed onto the souvenir then and there, right before their eyes. What makes this unique compared to other procedures is that the printer uses premium chocolate of all varieties, rather than just a mixture of fat and cocoa. However, this also leads to technical challenges: For the extremely temperature-sensitive raw material to be at all printable, it must be kept liquid in the print head; in the build chamber though, the temperature has to be so low that the chocolate solidifies before it loses the desired shape. To facilitate this, the cooled build chamber and the distance between print head and object are configured differently according to object size and chocolate type.
The setting changes again: to the Zurich career fair in Oerlikon. Right before the eyes of fascinated visitors, objects such as drinking bottles, vases, oversized cocoa beans or infinity cubes are being made out of chocolate. The 3D printer can do what casting moulds cannot. What looks like a gimmick has a serious background and is living up to the project’s original vision. The chocolate printer is intended to demonstrate the diverse nature of mechanical engineering and to illustrate how many fields of study and professions are behind the product. Project manager Patrick Fässler once worked for a chocolate firm himself as a teenager: “This product can get young people enthusiastic about studying technology,” he says with pride. As an example, for SwissSkills 2022, the Chocoformer printed the trophies for the STEM courses.
The chocolate industry is looking for attractive niches and unique selling points. The chocolate printer from the Eastern Switzerland University of Applied Sciences could help to provide just that, even though it was not originally intended to be a commercial product. Reactions from abroad, especially from countries without a chocolatier culture, suggest that there is a market: A Swiss machine that processes and refines a typically Swiss product with Swiss precision could become a fixture not only in Switzerland’s souvenir shops, but also in selected shops in Dubai, Seoul, Sydney and Tokyo.
Comprehensive and further information on the subject can be found in the article 3D printing of food.