With plastic pollution suffocating the planet, a new generation of bioplastics could change the game. Made from poultry waste, it replaces fossil-based polymers with biobased ones, bringing us closer to truly sustainable packaging. But experts warn: “For this to be a revolution, policies must support the sector.”
A fire is raging through a house. Half of it is already in ashes; the other half might still be saved but all we have is a bucket of water. That fire is the mountain of plastic waste we're producing, growing ever larger and smothering the environment. The bucket of water is bioplastics: a natural remedy but not a definitive solution.
The numbers are staggering: in 2022, each European citizen generated 186.5 kilograms of packaging waste, 29 kilos more than in 2011. Of that, 19% was plastic packaging waste, and only 41% of it was recycled. According to the UN, if we continue at this pace, by 2050 there could be more plastic than fish in the ocean by weight. Food packaging is one of the main culprits in this pollution crisis: nearly 37% of all food sold in the EU is wrapped in plastic.
In response, a wave of "green" alternatives has flooded the market: compostable plates, bioplastic cutlery, "eco" paper containers. But for anti-plastic activists, the issue isn't only what we use, it's how much we use. "We have an increase in the use of packaging and especially single use. Consequently, the EU's total packaging waste rose by some 20% over the last ten years. So first we must reduce packaging. We advocate for possible not using any packaging whenever that's possible," says Samy Porteron, Programme Manager at ECOS, an NGO that is part of the Break Free From Plastic movement.
Fast food chains are in the spotlight for the mountains of single-use packaging waste they generate, even when using supposedly sustainable materials. "When we talk about restaurants you can obviously be using washable and reusable plates and cutlery. When we talk about delivery, we've been advocating for systems that could also use reusable packaging, to complement promoting the practice of bringing your own packaging" Porteron adds. The key, they say, is to wash and reuse: plates, glasses, and cutlery made of ceramic, glass, metal, or other durable materials.
But if single-use plastic has been phased out in Europe and most materials on the market are "eco," why isn't it working? Biodegradable. Compostable. Recyclable. Biobased. The words may sound similar, but they're far from interchangeable. A bioplastic can come from natural sources but still be neither recyclable nor compostable and may contain harmful additives. Many bioplastics only break down under very specific conditions and often contain the notorious PFAS: persistent, endocrine-disrupting forever chemicals that leach into the environment. "People might not understand that a biodegradable plastic should not be thrown in the environment because it might not actually biodegrade as quickly as you think. They might not understand that a compostable product should not be recycled, for instance. Instructions for citizens for the separate collection of biodegradable plastic differ from one municipality to another, adding to the confusion", adds Porteron, pointing out that despite much educational effort, there's still a long way to go.
There's also the trap of "mixed" food packaging, paper lined with plastic, for example, which most consumers don't separate or recycle. "Consumer habits are hard to change. It's difficult to imagine fruit or bread packaging without a plastic window to see the product," explains Prospero Di Pierro, professor of biochemistry at the University of Naples Federico II.
In short, the devil is in the details in our daily routines. So, what's the path forward? "PHA biopolymers are the best candidates to replace plastic. Within this family, there's PHB: imagine a pearl necklace where each pearl is made up of 4 carbon atoms and 2 oxygen atoms (hydroxybutyrate). This gives it better technological characteristics and makes it the most promising material in current research. The addition of external molecules such as valerate to improve the polymer's properties raises the cost if microorganisms capable of autonomous production are not available," Di Pierro adds.
Still, producing this biopolymer comes with major challenges, starting from the pretreatment of the food waste used as raw material, to issues with logistics, transport and cost. Pretreatment is essential: to produce PHA at scale, microorganisms need to be fed with a carbon-rich but nitrogen-poor substrate. Processes like deproteinisation or fermentation are expensive and not always scalable. "Then there's the logistics. Transporting highly perishable materials to biopolymer factories is complex. Setting up facilities near food industries? Culturally, it's hard to convince food producers to start making bioplastics and economically it doesn't work yet, because bioplastic, being much more expensive than conventional plastic, isn't competitive without incentives," Di Pierro explains.
These are precisely the challenges that the European ViSS project aims to solve. Its goal? To sustainably and scalably produce PHB biopolymer, free from PFAS, using waste from the poultry and sugar industries.
"This project arose from the need to substitute fossil-based polymers by biobased polymers. Our polymers are biobased and biodegradable, produced by microorganisms; they are completely safe and biodegradable in all environments: in soil, in freshwater, in seawater because we only add safe and sustainable additives," says Carmen Fernández Ayuso, PhD, head of coordination and R&D management at CETEC in Murcia, Spain, and ViSS project coordinator. The additives don't interfere with the degradation process. "This is an innovative approach in our project because we design the polymer taking into account the end of life to ensure a safe biodegradation and not endangering the environment and the health of users," she adds.
Practically, the process begins with poultry waste, feathers and bones, and sugar industry by-products, all sourced locally to cut transport costs. "Also, we use plastic reactors instead of steel reactors that are costly," explains Fernández Ayuso, and the whole process runs under non-sterile conditions, saving even more. A microorganism digests the substrate and starts accumulating PHBV inside its cells. This is then extracted and purified to produce a biodegradable powder or plastic granule, ready to be formulated and turned into film, packaging or other items. "One of the main points is that in our process, our product has 15 to 30% of hydroxyvalerate. That makes it less crystalline and it has flexibility", adds Fernández Ayuso, solving one of the biggest limitations of this type of bioplastics: their rigidity.
If PHBV biopolymer production can be scaled cost-effectively, it would mark a real revolution in the world of plastics. But one final hurdle still stands: the price. Experts are calling for policies that support the sector, to make bioplastic produced in Europe competitive, not 2 or 3 times more expensive than fossil-based plastic, and not outpriced by extra-EU imports. In short: to give it the power to put out the fire.
Article by Gioia Salvatori