Bananas grow off a trunk-like structure, called the pseudostem. This section of the plant is usually discarded, but thankfully now it may soon find use as a plastic alternative. Australian researchers have successfully transformed banana agri-waste from the banana industry into non-toxic, biodegradable, bioplastic.
The researchers, at the University of New South Wales (UNSW), said that growing bananas is a wasteful form of agriculture because only 12% of the plant is used, with the rest discarded as waste. This significant amount of banana agri-waste provides an abundant supply of raw materials, which makes the crop an enticing target for the industrial production of bioplastics.
Jayashree Arcot, from UNSW, explained:
What makes the banana-growing business particularly wasteful compared to other fruit crops is the fact that the plant dies after each harvest. We were particularly interested in the pseudostems – basically the layered, fleshy trunk of the plant which is cut down after each harvest and mostly discarded on the field. Some of it is used for textiles, some as compost, but other than that, it’s a huge waste.
To bring value to that waste, Prof. Martina Stenzel and Assoc. Prof. Jayashree led a team at UNSW to develop a new recycling process, with successful results. First, the team chopped up the pseudostem into pieces, then dried those pieces in an oven at a low temperature. The baked bits were then crushed into a fine powder and washed via soft chemical treatment. This treatment separates a material called nanocellulose from the rest of the powder. Sheets of plastic are made from that nanocellulose.
When the process is complete, the resulting material has a consistency similar to baking paper and could be used in a variety of food packaging or plastic bags. It can be recycled three times without losing its quality, and when it’s tossed in the soil, it decomposes.
Arcot said:
There are some options at this point; we could make a shopping bag, or depending on how we pour the material and how thick we make it, we could make the trays that you see for meat and fruit. Except, of course, instead of being foam, it is a material that is completely non-toxic, biodegradable, and recyclable.
Now the team is looking for industry partners who are interested in taking the process to a commercial production level and making it as profitable as possible.
