If you're trying to woo that special someone, instead of just bringing them a box of ordinary chocolates, how about a box of chocolates that look like you? You're right, that would just be creepy, but chocolates formed into user-defined shapes are nonetheless now a possibility, thanks to a 3D chocolate printer developed at the University of Exeter.

Instead of being a product that people would buy and keep in their homes, the developers of the printer see it being owned by candy-making companies. Customers would submit their designs via a web interface (which is currently in development), then the company would print out the chocolates and deliver them. Less imaginative users could also view existing designs, and copy or modify them.

"What makes this technology special is that users will be able to design and make their own products" said lead researcher Dr. Liang Hao. "In the long term it could be developed to help consumers custom-design many products from different materials but we've started with chocolate as it is readily available, low cost and non-hazardous ... In future, this kind of technology will allow people to produce and design many other products such as jewelry or household goods. Eventually we may see many mass produced products replaced by unique designs created by the customer."

Like most 3D printers, the device works by depositing successive layers of the building material. Chocolate presented a challenge, however, as it requires precise heating and cooling cycles. The Exeter team therefore had to create new temperature and heating control systems, in order to keep the chocolate liquid enough to work with, yet cool enough that it would set upon deposition.

The University of Exeter is developing the 3D chocolate printer in collaboration with Brunel University and software developer Delcam. The project is funded by the Research Council UK Cross-Research Council Programme - Digital Economy and is managed by the Engineering and Physical Sciences Research Council.