Food waste causes a range of environmental problems when left to rot in a landfill. A staggering amount, 1.3 billion tons of food, is wasted globally every year, according to the United Nations Environment Program (UNEP). The carbon footprint of all that wasted food is estimated at 3.3 billion tons of carbon equivalent.
Wasted food also means wasted water. The amount of water used to produce food that is wasted is equivalent to the annual flow of Russia’s Volga River or three times the volume of Lake Geneva. That is not good at any time — but becomes particularly poignant during a time when the entire state of California is in its third year of drought. There is also an economic cost to food waste — $750 billion a year.
On to another problem: Conventional plastic is made from petroleum, a fossil fuel, and contributes to climate change. Bioplastics are made from plant material and are an alternative to conventional plastic. However, the multiple steps needed to produce bioplastics mean more energy is needed. And the crops used to produce them, like corn, are probably better suited for human consumption.
As a solution, a group of scientists at the Italian Institute of Technology (IIT) in Genova, Italy, are working on ways to create bioplastic from food waste. Their results were published earlier this summer in American Chemical Society’s (ACS) journal Macromolecules.
IIT scientists looked at the process for creating cellophane, which includes passing cellulose — the material that makes up plant cell walls — through acid and alkali baths. They found out that when cellulose derived from cotton and hemp is dissolved in the common chemical trifluoroacetic acid, it is converted to a form that can be molded into plastic without having to be processed any further.
They tried the same process on vegetable waste products that included rice hulls, cocoa pod husks, spinach and parsley stems obtained from an Italian company that powders vegetables to be used in vegetables drinks and colored pasta. As Ilke Bayer from IIT said, “These are the parts we don’t want to eat.” Or as the scientists wrote in their study published in Macromolecules, “Bioplastics with a wide range of mechanical properties were directly obtained from industrially processed edible vegetable and cereal wastes.”
From electronics to food packaging, plastics are so widely used that life as we know it would come to a standstill without them. Perhaps one day bioplastic from food waste will be used in the various applications our 21st century lives depend on.
Image credit: Muu-karhu