With casein, a protein in milk, turns out to be a film to be made that is more environmentally friendly than hydrocarbon made plastics. The new material is presented today at the American Chemical Society.
The caseinefolie may provide a solution to the milk surpluses. By the large amount of milk cows in Europe there is too much butter and milk on the market which then have to be dumped elsewhere to keep the prices reasonable. As a part of that milk could be converted in packaging material, supplies that possible profit on.
Environment friendly or waste of food
Casein is the main protein in a glass of milk. The researchers of the ACP and the American Department of agriculture isolated the protein and made extremely thin pieces of foil of a casein paste very thin out to smear and let dry. The resulting material appeared excellent decay. Through the small pores in the film let it much less oxygen than just plastic wrap, and oxygen is one of the most important causes of food spoilage. In addition, casein fine edible and biodegradable. In that sense, it is so environmentally friendly.
On the other hand it remains a milk product, and cows are known as big polluters: the methane gas from manure and their winds are important sources of greenhouse gases. Meanwhile, there are already more environmentally friendly biodegradable films, think of the very creaky mais foil, that often go to organic products is in the supermarket.
Citrus fruits to enforce material
Although the casein foil his work did well, it was not very flexible. Therefore, the researchers added citrus pectin, a substance from the peel and seeds of citrus fruits such as oranges and lemons. The flexibly and more resistant to water.
The material can unfortunately not apply if any packaging, it is not firm enough. But because it counteracts decay there is far less and less needed if thick plastic packaging a simple sleeve is enough.
In addition, it can also be used as a spray to casein food were to protect against moisture.
Compare it with corn flakes, which are provided with a sugar coating to keep them crispy after being in the milk or yogurt. Casein coating keeps the corn flakes also crunchy, but is much less sweet and therefore healthier.