This pasta is no limp noodle. When imprinted with grooves, it can morph into tubes, spirals and other traditional shapes as it cooks. This new technique would allow uncooked pasta to take up less space. That means it would need less packaging.
Pasta lovers “are very picky about the shapes of pasta and how they pair with different sauces,” says Lining Yao. She studies the design of smart materials at Carnegie Mellon University in Pittsburgh, Penn. Flat pasta like spaghetti holds less sauce than twisty types like rotini. But those shapes come at a cost: bigger packages. For some curly pasta, more than 60 percent of the package holds just air.
Yao and her colleagues stamped a series of grooves onto one side of each noodle. Then they cooked that pasta. The pasta absorbed water as its cooked. But the liquid couldn’t penetrate as fully into the grooved side. So that side swelled less than the smooth side. That asymmetric swelling bent the previously flat noodle into a curve. By changing the arrangement of the grooves, the researchers controlled the final shape.
Computer simulations of swelling pasta replicated the shapes seen in the experiments. Yao and her colleagues reported their research May 5 in Science Advances.
The technique isn’t limited to pasta. Experiments using silicone rubber in a solvent produced similar results. But the silicone rubber didn’t hold its shape as the pasta did. The silicone eventually absorbed enough solvent to flatten out again. The pasta stayed curly because the starchy pasta gets gluey as it cooks. That helps lock in the twists by fusing neighboring grooves together.
Removing the silicone from the solvent caused the material to bend in the opposite direction. This reversible bending process could be useful. Bendy silicone could make a grabber for robot hands that opens and closes.
The pasta makes good camping food, Yao says. A member of her team brought it along on a recent hiking trip. The pasta slips easily into a cramped pack. But it cooks into a satisfying shape.