Aimplas’ EU-funded Dafia project converts fish waste into food packaging biopolymers

09 Apr 2021 --- Dafia, an EU-funded project led by Spanish research group Aimplas, is releasing the results of an investigation into turning fish and municipal waste into biopolymers and other barrier packaging materials. 

The researchers say they have optimized extraction techniques to obtain gelatine and low-molecular-mass nucleic acids from salmon skin, viscera and backbones using herring stock and herring milt as raw materials.

The project, which finished last December, seeks to provide the automotive and food packaging industries with environmentally sustainable solutions by developing biopolymers, flame-retardant additives and barrier packaging similar to fossil-based products. 

Dafia is reported to be in line with circular economy criteria and funded by the EU’s Horizon 2020 program.

The extraction process
Speaking to PackagingInsights, Dr. Laura Marti Montaner, the decarbonization group leader at Aimplas, explains the extraction process used in the research. 

“After a three-stage processing of fish waste, highly pure gelatine (odor-free and white) is extracted, which can be used in an optimized water-based formulation (plasticizer and antimicrobial substances) to produce food coatings by lamination or dip coating to extend shelf life.” 

The results show this bio-based solution achieves permeability values comparable to petrol-based counterparts – ethyl vinyl alcohol (EVOH). 

It also produces antioxidant properties when released in aqueous food simulants and creates antibacterial activity, in vitro, against Staphylococcus aureus, says Marti Montaner. 

“Nucleic acids extracted using the technology developed could be used in different flame-retardant applications like textile coatings but also to make food and cosmetic ingredients,” she highlights. 

These findings could, therefore, be used to create edible coatings that extend food shelf life and offer antibacterial protection in the future . 

The researchers hope that in future, fish waste could be used en mass for packaging.Research challenges and commercialization
The key technical takeaways from the project were the abilities to use:

• Monomers to make bio-based polyamide. 
• 1,5-pentane diamine as an alternative to 1.6-hexamethylendiamine.
• Bio-based flame retardants based on fish waste as alternative to halogen-based flame retardants.
• Fish gelatine as an alternative to mammal gelatine.

Marti Montaner lists a number of challenges the team faced in reaching these discoveries, including the fact that the lipid content of gelatine highly influences packaging barrier properties. 

“The trials at semi-industrial lamination showed variability on the properties along with the film, so low-speed drying was required in the lamination line, which reduces the productivity.”

“Modification on the percentage of plasticizers will be evaluated.”

She asserts that further research needs to be done to determine whether the findings would be applicable to industrial packaging production. 

“Trials at larger scale are needed to ensure the commercialization would be possible since so far, the costs are too high in most of the products developed.”

“A life cycle analysis showed the environmental impact on fermentation processes is still high, and renewable energy would be needed, and downstream processing would improve the yield and the recovery of the materials used.” 

However, the production of bio-based coatings using gelatine and the production of flame-retarding is environmentally comparable to traditional methods, she says. 

Eating into packaging waste 
A number of other research projects have sought to find new ways of extending food shelf life and offsetting associated carbon emissions. 

US-based Apeel Sciences developed a protective peel made from fruit materials added to the surface of fresh produce to slow water loss and oxidation – the primary causes of spoilage. The technology extends the shelf life and transportability of strawberries, peppers and other fresh produce, with reduced reliance on refrigeration and a controlled atmosphere.

Meanwhile, Indonesian social enterprise Evoware is providing plastic-free alternatives to single ware-use products using seaweed. The food wrappings and sachets are biodegradable, compostable, edible and nutritious, and used for a wide range of dry applications, including instant coffee, noodles or medical supplies.

By Louis Gore-Langton