There’s an old saying that sometimes you can have your cake and eat it, too.
And soon you also may be able to have your food packaging and eat it, too.
The team hopes their edible plastic can someday reduce dependency on plastic wrapping.
Every year Americans discard about 33 million tons of plastic. Plastic is a popular material for food packaging because it’s easy to mold and print on, as well as cheap to produce.
A small percentage of this waste is recycled, but the rest ends up in landfills. Once in the landfill, it can take up to 1,000 years to completely decompose.
Eat it or compost it
The Dairy and Functional Foods research unit is a branch of the U.S. Department of Agriculture. It’s headed by Dr. Peggy Tomasula. Dr. Laetitia Bonnaillie is the principal investigator in this study.
“One thing we like to do is utilize excesses and leftovers,” Bonnaillie told Healthline. “We produce more milk than we consume in the U.S. … this was one idea that Peggy had to try to utilize the excess milk.”
The plastic film looks just like Saran Wrap.
“The difference is that you can eat it. It is made almost entirely of milk products.” Bonnaillie said.
Casein doesn’t have a taste, but the wrapping is biodegradable if you choose not to eat it.
Another advantage of the casein packaging is that it creates a better oxygen barrier for food than plastic does.
“When you put food in a [plastic] sandwich bag it oxidizes quickly. It gets a stale taste to it,” Bonnaillie said. “The protein-based plastic does not do that. It blocks the oxygen a lot better.”
Americans wasted 133 billion pounds of food in 2010. Packaging that keeps food fresh could help reduce the amount of food that is tossed out.
The team believes their casein packaging would work well for single-serve food products.
Bonnaillie uses individually wrapped cheese sticks as an example.
“You pick up cheese sticks and there is almost more plastic than cheese.” she said. “That’s a lot of plastic that goes in the trash.”
Bonnaillie says the casein packaging could be used to individually wrap the cheese sticks. The wrapped cheese sticks would then be placed into separate packaging that would keep the casein packaging clean and safe to eat.
The casein packaging dissolves in water, which would make it a good receptacle for single-servings of soup or coffee. The package could be dropped directly into hot water and would dissolve entirely, reducing waste.
Casein can also be used as a spray coating on foods such as cereal to keep the cereal from losing its crunch. Currently, cereal manufactures use sugar to preserve cereal.
Casein and whey are the two main proteins found in cow’s milk.
According to the Mayo Clinic, milk allergies are one of the most common food allergies. People who are allergic to milk are also experiencing a reaction to either casein or whey.
These allergies could potentially limit the uses of the casein packaging to products that are already made with dairy, are usually used with other dairy products, or have other common allergens, such as nuts.
The water soluble properties that make the casein packaging useful for single serve pouches of coffee or soup also limits the environments they can be exposed to before the food is consumed.
Foods packaged in the casein plastic will also need a secondary package to protect the packaging from getting wet and dissolving, or getting dirty and being unsuitable for consumption.
The team added citrus pectin, a fruit carbohydrate, to the packaging to make it more resistant to the environment. But more work is needed on the packaging before it’s available for use in stores.
“We have to find a balance between a strong film that can be handled easily, that is nice and flexible enough to wrap food ... that has a good clean shiny finish and at the same time is strong and resistant to temperature and normal storage conditions, like a hot day in your kitchen.” Bonnaillie said.