"The process," Schiraldi said, "is simplicity itself."
The researchers start by throwing a scoop of clay and some water into a kitchen blender. Two minutes of mixing produces what Schiraldi's students call a clay smoothie.
Next, they add some casein powder, a dried version of the most common protein in milk. The final ingredient is a tiny amount of a glycerol-based material, which basically stiffens up the solution's chemical bonds.
After running the blender one last time, the scientists pour the dirty-looking water into molds and freeze them like ice-cubes. Then, they freeze-dry it get all the water out.
The result, Schiraldi said, is a material that has all the same properties of Styrofoam, but is 98 percent bio-based. At 100 degrees Celsius (212 degrees Fahrenheit), the milk-containing foam lets out a few drops of water. But it stays sturdy up to 200 degrees Celsius (392 degrees Fahrenheit).
In tests conducted by the U.S. Department of Agriculture, close to a third of the new material broke down after about 45 days in industrial compost conditions. That's a huge environmental leap beyond Styrofoam and other types of Expanded Polystyrene Foam, a category of materials that is often used as disposable packaging for electronics and other products.