Could Milk Be the Future of Food Packaging?

After eating string cheese, people typically toss the thin plastic wrapper in the trash can. Thanks to a new design, cheese lovers might be able to munch on the package too.

Researchers at the U.S. Department of Agriculture have developed an edible and biodegradable food packaging material made out of casein, a milk protein. On Thursday the team is presenting its research at the 252nd American Chemical Society National Meeting & Exposition.

“Using milk to make a new type of food [packaging] that also protects our food sounded like a good idea,” Laetitia Bonnaillie, one of the team’s lead researchers, told TakePart. “The package is edible, so there will be zero waste, and because it’s a protein, it will also add nutrition.”

To create the packaging, researchers mixed the protein with water, along with glycerol and citrus pectin (both of which are safe to consume). The liquid is then laid out on a sheet to dry, resulting in a malleable material that looks much like the plastic wrappers seen in grocery stores across the country.

Bonnaillie and her team have tested the casein on multiple food items, such as single-serve soup and instant coffee packets. Rather than dumping the product out of the package, the wrapper dissolves in hot water. The film doesn’t affect the taste of the food, although Bonnaillie said flavors and nutrition additives can be incorporated.

The casein package wouldn’t eliminate waste entirely. Because the edible packaging would need to be kept clean enough for consumption, individually wrapped food items would need to be sold in larger plastic or cardboard boxes. But in a market where items come in many layers of packaging and the average American tosses about four pounds of waste daily, researchers expect that removing one plastic product will make a dent in waste.

Along with preventing wrappers from heading to the landfill, the milk casein can cut down on food waste. The casein packaging is up to 500 times more effective than plastic at blocking oxygen from the food it protects, allowing items to stay fresh longer. It can also be used in place of chemicals as a protective spray on pizza boxes to prevent grease from leaching through the cardboard or in place of sugar coatings on cereal flakes. Often, sugar is used to help the cereals maintain their crunch. The casein can prevent cereal from becoming soggy but without the extra calories.