MIT Uses 3D Printing to Create Shape-Shifting Noodles

Is there anyone who isn’t fascinated and delighted by the many shapes of pasta? There may be some people who don’t get excited about pasta, yes, and I do apologize for raving about pasta shapes more than once. I know I’m not the only one, however, judging from the 3D printed pasta design contests out there, and now even MIT has gotten in on the pasta design game. Researchers at the college’s Tangible Media Group have developed what may be the coolest pasta yet – shape-shifting pasta.

I once bought “blooming tea” at a farmer’s market. It came as a container of tea leaves wrapped up into tight spherical shapes. When dropped into hot water, they unfurled and revealed hidden flowers. Very fancy – and MIT has developed pasta that behaves in a similar manner. The researchers created flat discs of pasta that wrap around beads of caviar, as well as spaghetti-like pasta that divides into smaller noodles when submerged in hot water. (No more having to cut up spaghetti for kids!) They also created flat noodles that fold into shapes like flowers when placed in water.

It’s not all for fun, though. Shape-shifting pasta could be used to save valuable packaging space, by fabricating it in flat sheets that form into three-dimensional shapes only when cooked.

“We did some simple calculations, such as for macaroni pasta, and even if you pack it perfectly, you still will end up with 67 percent of the volume as air,” said Wen Wang, a former graduate student and research scientist in MIT’s Media Lab. “We thought maybe in the future our shape-changing food could be packed flat and save space.”

Wang and Lining Yao, another former graduate student, had been studying the response of different materials to moisture at MIT. They had been working with a particular bacterium that shrinks, expands and changes its shape in response to moisture – and that also happens to be used to ferment soybeans for a popular Japanese dish called natto. Yao and Wang wondered if other foods could be made to change their shapes when introduced to water.

As you’ve seen if you’ve ever made Jell-O, gelatin expands when it absorbs water, so the researchers began experimenting with the substance. It expands to different degrees depending on its density, so they created a flat, two-layer film made from gelatin of two different densities. The top layer was denser than the bottom, and thus absorbs more water, so when the structure was immersed in water, the top layer curled over the bottom layer, forming an arch shape.

To create different shapes, Wang and Yao 3D printed strips of edible cellulose over the top layer of the gelatin. Cellulose absorbs very little water, so it acted as a barrier over the top gelatin layer, keeping it from absorbing water and expanding. By 3D printing the cellulose in specific patterns, they were able to control how the structures responded and the shapes they formed.

“This way you can have programmability,” Yao said. “You ultimately start to control the degree of bending and the total geometry of the structure.”

The next step was to see how their formula would translate to real food. They contacted the head chef at a high-end Boston restaurant, and the three of them experimented by designing two different types of pasta: a flat gelatin disk, flavored with plankton and squid ink, that curls around caviar in water, and a fettucine-like design made from two types of gelatin that melt at different temperatures, causing the noodles to divide when hot water or broth melts certain sections.

“They had great texture and tasted pretty good,” Yao said.

The researchers recorded the cellulose patterns and the dimensions of all of the structures they created, which included flower and arch shapes as well as more traditional noodle shapes such as macaroni and rigatoni. They then tested the mechanical properties, such as toughness, and placed all of the data into a database, after which they created computational models and built an online interface where users can design their own shape-shifting noodles.

“We did many lab tests and collected a database, within which you can pick different shapes, with fabrication instructions,” Wang says. “Reversibly, you can also select a basic pattern from the database and adjust the distribution or thickness, and can see how the final transformation will look.”

While the researchers used a 3D printer to print the cellulose patterns onto the gelatin, they have also described other ways of laying the material down, such as screenprinting.

“We envision that the online software can provide design instructions, and a startup company can ship the materials to your home,” Yao said. “With this tool, we want to democratize the design of noodles.”

The research was funded in part by the MIT Media Lab and by Food + Future. The research was published in a paper entitled “Transformative Appetite: Shape-Changing Food Transforms from 2D to 3D by Water Interaction Through Cooking,” which you can access here. Authors include Wen Wang, Lining Yao, Teng Zhang, Chin-Yi Cheng, Daniel Levine, and Hiroshi Ishii. Share your thoughts in the Shape-Shifting Noodles forum at 3DPB.com.

[Source: MIT News / Images: Michael Indresano Production]