Organic plastic substitute:
Banana peels as environmental heroes?

Do it yourself

What do banana peels, eggshells and tomato skins have in common? Quite simply, they could be the path to a new future. They, and some other food waste, can be reused (even away from the compost pile). For example, the soot found in rubber tires could be replaced with eggshells and tomato skins. Other plants or biological materials can also be used, examples include natural rubber from dandelions, packaging from mushroom mycelium, and plastic from starch.

 

And you too can easily make your own "plastic" bowl and decorative stones. 100% organic and easily degradable, perfect for the environmentally conscious DIY enthusiast.

Let's go - have fun!


You want to learn more about plastic and its alternatives?

Why do we need a replacement for plastic at all? Is it even possible? And what exactly is bioplastics? Below you will find additional information and links to information material that we have found online on the topic!


Overview

  • Suitable for age group: 8 years and older

  • Especially interesting for: Children and young teenagers, crafters, gift seekers and environmental activists

  • Preparation time: about 1 ½ - 2 hours


Material

  • You need (to make a small bowl i.e.) :

  • Sharp knife

  • 2 Banana peels

  • 1 pinch thyme

  • 1 tea spoon cinnamon

  • 1 teaspoon vinegar

  • 1 tea spoon glycerin (or honey)

  • Cold water

  • Blender

  • Pot (preferably not the favourite pot, but an older one)

  • Wooden spoon/ chopsticks

  • coffee-/tea filter

  • Sieve

  • An old fabric cloth

  • Bakery paper

  • Bowl, egg cup, small mould ...

  • Possibly transparent film and rolling pin


Preparation

Step 1: Blend the banana peels

Cut the banana peels into small pieces and put them in the blender with the water.
The amount of water varies, you want to have a nice mash at the end (about 220ml).
The fewer pieces left, the better. The blender will finely cut the cellulose chains that are in the banana peel.


Step 2: Add the remaining ingredients

Add glycerin, cinnamon and vinegar (1 tsp each), and a pinch of thyme. You need the vinegar to further unravel the junctions of the cellulose chains, while the glycerin makes them more flexible.

Cinnamon and thyme are food preservatives. You add them to prevent the banana peels from getting moldy.
They also give off a pleasant smell.

Alternative

If you do not have a blender, you can also cut the banana peels very small and then use a hand mixer to further downsize the ingredients. But make sure to cover the whole thing well!


Step 3: Boil it up

First boil the mixture in the pot over medium heat, stirring constantly (~10min). Then continue stirring at a lower temperature for 5 min. By heating, new long starch chains are formed, the mixture becomes sticky and the cellulose is trapped in it.


Tip

In any case, do not use your best pot. The heating and the addition of the glycerine will attack the coating of the pot.

For rinsing, it is best to use cold water, then you can avoid the need for soaking.


Step 4: Cool down and drip dry

After cooling, put the mixture in a sieve with a coffee filter and let it drip off. The remaining water is squeezed out with the help of the old cloth rag. Removing the excess water will cause the cellulose fibers or rather the new starch chains to stick together.


Step 5: Shape the material according to your own imagination

You have several options to shape the mixture. You can use a bowl (egg cup, box...; covered with or without transparent film) to shape it or fill cookie cutters.


Step 6: Let it dry

Let your artwork dry in the air for about 4 days or in the oven for about 2 hrs at 80-100°C. After drying you will have a material that seems to be a mixture of plastic and rough cardboard. The starch from the banana is the skeleton, while the cellulose provides its rigidity.


Have fun
discovering and exploring!


Learn more!

Plastic is very important to our society and the progress we have made. But in recent years it has become clear that the long-term consequences are greater than the benefits of plastic. For this reason, more and more research is being done to find alternatives.
This includes bioplastics. What is bioplastic? On the one hand, they are plastics that are biodegradable (can be broken down by organisms). However, this does not mean that these plastics are renewable. On the other hand, plastics made from renewable biological materials that are not always biodegradable are also called bioplastics. So when you hear bioplastic, it doesn't necessarily mean renewable and biodegradable. So you can't put all food boxes, plates, cups or plant pots that have bioplastics on them in the compost (You can find out more here: Biobased and biodegradable plastics | Federal Environment Agency).

A big advantage of the "banana plastic" is that only the peels are used and you can eat the actual fruit.







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