Milk protein used to make biodegradable food wrap
From the CBC
A new biodegradable film made of milk protein has the potential to keep food fresher and replace plastic wraps, according to researchers from the U.S. Department of Agriculture. Lead researchers Peggy Tomasula and Laetitia Bonnaillie plan to present their work before a conference of the American Chemical Society on Sunday in Philadelphia.
Bonnaillie says the substance they created is made of casein, a milk protein, with the addition of citrus pectin and some salts to make it stronger and more resistant to moisture. It behaves much like a plastic cling wrap, but it’s biodegradable, even edible, and there is no danger of harmful compounds leaching into food. The film can be folded and sealed around food products. It is as strong as plastic wrap but not as sticky.
For products such as cheese slices, packaged meat or individually wrapped snacks, it would take packaging that now goes into landfill and replace it with a material that breaks down in the environment.
Tomasula and Bonnaillie work in the dairy research unit of the USDA and hit on the idea of creating a packaging material when they were looking for a use for some of the dry milk that is produced in excess in the U.S. As milk consumption falls, dairy farms have continued to produce too much milk, which is being stored as milk powder.
The casein film could also help keep food fresher longer, as protein-based films are powerful oxygen blockers that help prevent food from spoiling. As an oxygen barrier, the casein film is 250 times better than plastic wrap, Bonnaillie said. It also has the potential to block light more effectively than plastic.