EDIBLE origami that transforms after being dropped in water has been created using 3D printing. The technique, which produced pre-defined shapes from flat sheets, could save food shipping costs or open up new avenues of Heston Blumenthal-style gastronomy.
When we buy packaged food, we are often buying more air than we are product by volume. A perfectly-packed bag of macaroni pasta, for example, contains only 33% of the actual foodstuff – the rest consists of gaps between and within pasta structures. If this could be packed flat, shipping costs could be reduced through denser stocking of goods.
Now, researchers at MIT in the US have pioneered a practical solution to such issues, using a technique they describe as “culinary performance art”.
The method involves layering films of gelatine with different densities, which expand to varying degrees as they absorb water. 3D-printed strips of cellulose, which absorb very little water, are then 3D-printed onto the top layer. These materials could potentially be packed flat, reducing shipping costs.
The strategically-applied cellulose acts as a water barrier on the gelatine, predictably shaping the structure’s response to water. Lining Yao, the paper’s lead author, said: “This way you can have programmability. You ultimately start to control the degree of bending and the total geometry of the structure.'
It was possible to create a number of different shapes from the gelatin films – from various pasta configurations to flowers and horse saddles. The researchers recorded the cellulose patterns and the dimensions of all of the structures they were able to produce, and organised this on a database alongside mechanical properties such as toughness. They then built computational models of the material's transformations for an online interface aimed at allowing users to design their own edible, shape-transforming structures using techniques such as screenprinting.
Co-author, Wen Wang, said: 'You can select a basic pattern from the database and adjust the distribution or thickness, then see how the final transformation will look. We envision that the online software can provide design instructions, and a startup company can ship the materials to your home. With this tool, we want to democratise the design of noodles.'
The researchers also collaborated with a professional chef to see the applications of their technology in fine dining. One of their creations was a transparent disc of gelatine, flavoured with plankton and squid ink, that instantly wrapped around small beads of caviar; the other was a long fettuccini-like strip, made from two gelatins melting at different temperatures, that spontaneously divided when hot soup melted away certain sections.
Yao said: 'They had great texture and tasted pretty good.'
Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems: http://doi.org/b7n8
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