Biodegradable food packaging
Why is it useful?
Over 40% of the plastics produced in the world are used in packaging applications with food packaging being the biggest culprit. We are already producing tens of millions of tonnes (over 10,000,000 tonnes!!) of plastic food packaging each year and this amount is predicted to grow with the continuing shift towards ready made, single-serve products.
Whilst recycling is a top-priority for improving waste management, certain products are notoriously hard to recycle. A recent report from the Ellen MacArthur Foundation estimated that up to 30% of plastic packaging materials will never be eligible for recycling unless we fundamentally redesign them!
‘…up to 30% of plastic packaging materials will never be eligible for recycling unless we fundamentally redesign them’.
This is due to a variety of reasons. Some niche materials are used in too small a quantity to justify the recycling infrastructure, some plastic products are considered too small for practical sorting, and some packaging products are prone to being contaminated with organics (particularly food) or chemicals.
Another category of materials that are hard to recycle are multi-layered plastic materials (thin films made of many types of different plastics layered one on top of another). You would probably be amazed how many of the plastic films you touch on a day-to-day basis are actually composed of multiple layers of different plastics (sometimes up to 7 layers), as they are normally indistinguishable from a package made of only a single material. You particularly find these multi-layered plastics in personal care products and food packaging.
Multiple layer plastics are finding favour in food packaging because they can reduce food spoilage by controlling the movement of gases and water vapour between the packaged item and the atmosphere. However, whilst reducing food spoilage is an environmental win, when it comes time for disposing of the packaging, separating the layers is expensive and near impossible, making recycling unlikely. Currently, these sorts of materials are destined for landfill or incineration and thoughtful materials design and innovation will be required in order to change.
This is why the world should be interested in biodegradable food packaging.
In these applications, multi-layer, biodegradable packages could still offer a reduction in food spoilage but also expand the available waste management options to include composting and anaerobic digestion. Therefore, they could be disposed of along with food waste reducing reliance on landfill and incineration. Exploring the development of such materials is part of the focus of my PhD and the bioplastics team at the University of Queensland. I’ll be further exploring this topic in articles to come, including some of the other big problems that would need to be addressed before biodegradable plastics will become a viable option.
However, whilst being excited by the prospect of smart materials design, every person should know that they too are needed as a part of the solution. Below are a few ways you can reduce your use of food packaging or responsibly dispose of packaging in the short-term:
- Be a conscious shopper, and avoid items that seem unnecessarily packaged — e.g. individually wrapped cheese slices, packaged bananas, products that have a packet inside another packet inside another packet.
- Buy meat etc. in larger portion sizes and put some in the freezer.
- Visit and support your local farmers market more often.
- Say no to the soy sauce fish!
- (Australia) Save all of your soft film packaging in a bag under the sink and take it to a RedCycle container when you visit a Coles store (this way it at least gets made into park benches etc.).
