Researchers have developed a new biodegradable packaging material for hamburgers that could replace fast-food restaurants’ paperboard
clamshells–the same paperboard that pushed polystyrene containers out of the market years ago.
The new material, which is made of wheat and feels like dense Styrofoam, could also be used to make disposable coffee cups, plates, supermarket meat trays, and carryout boxes, U.S. Department of Agriculture chemist Geoffrey A. R. Nobes reported.
Nobes and his colleagues, who work for the USDA’s Agricultural Research Service in Albany, Calif., made the new material by molding and baking a dough-like concoction of wheat starch and fibers from wheat straw. Afterward, the scientists examined the material with a scanning electron microscope and tested it for flexibility, density, and strength. They found that their new material could form a clamshell package that’s stronger and insulates better than paperboard, although not quite as well as polystyrene.
Potato-starch clamshells already exist, but wheat versions offer some advantages, Nobes says. For example, in North America wheat starch is cheaper and more abundant than potato starch. In addition, he says, potato-starch clamshells include calcium carbonate, making them heavier than wheat-based clamshells.
One drawback of wheat clamshells is that they aren’t water and ketchup resistant unless they get a coat of shellac, Nobes says. He’s now trying to find a recipe for wheat dough that will make the shells better able to handle a burger with the works.