FASTER WAY TO MAKE BIOPLASTICS FROM PLANT MATERIAL WASTE

Italian Researchers Find Easier Way to Turn Cocoa Pod Husks Into Food Wrappers

Recycling food waste isn’t all about composting. Researchers at the Italian Institute of Technology in Genova, Italy, have been experimenting with cocoa pod husks and other waste material to create a new type of bioplastics. A frequent criticism of bioplastics is that they are made from crops, such as corn or potatoes, that could otherwise be used for food. This led the team of researchers in Genova to look at other ways of producing cellophane, which is frequently used in food packaging.

The team discovered a faster way to turn cellulose from hemp and cotton into cellophane, and without the need for the usual complex processing. Instead of using the traditional method of multiple baths of acids and alkalis, they dissolved the cellulose in trifluoroacetic acid which produced a substance suitable for moulding into plastic, without the need for further treatment.

They then applied this technique to vegetable waste products, such as rice hulls, cocoa pod husks and spinach and parsley stems, which yielded positive results. They found these new plastics had different properties to traditional plastics and also inherit certain attributes of the original plants, for example cinnamon plastic could be antibacterial. The merit of turning a waste product into something useful makes great sense.

For example, each ton of dry cocoa bean creates ten tons of cocoa pod husk waste. This waste material is usually discarded, but could be put to use in other ways. In Brazil, researchers believe these pod husks could become a valuable source of pectin for the food industry. Pectin is normally found in jams and other processed foods, as a stabilizer or gelling agent.

Cheaper and more sustainable bioplastics could soon find their way into our weekly shopping. However, some commentators remain unconvinced, “I would be sceptical that, in the full economics of it, you could keep that benefit of the waste being cheaper than buying starch,” says Paul Mines of UK based Biome Bioplastics.