01 March 2024
Coming out of its shell
Shell waste from commercial fishing has long been an untapped resource, but new research suggests it could have great potential for industrial packaging applications.
It has been reported that for each species of shellfish harvested, around 10 million tonnes of waste are generated annually and dumped, mostly into open fields or nearby water bodies, leading to ecological issues such as awful smell, soil contamination, and water pollution. However, these vast quantities of waste may present an interesting opportunity to solve an ongoing issue in the packaging sector. Researchers at Teagasc are enthusiastically involved in the IMPRESS project, a European Union research project chiefly focused on building a waste-sustainable, aquatic food value chain. The researchers are currently focused on extracting targeted compounds from crustacean shells and raising biopolymers from the shell waste, explains Rifna Jerome, a post-doctoral fellow at Teagasc Ashtown’s food research centre: “Imagine taking this apparent waste matter — shells, once simply discarded as mere leftovers from the ocean ecosystem — and transforming it into a highly valued resource. Shell waste has a potential place at the cutting edge of biopolymer applications. This research will not only valorise shell waste, but marks a fascinating next step in the quest to develop robust, eco-friendly substitutes for polymers – materials which themselves raise numerous environmental concerns.
“The project’s groundbreaking methodology encompasses integrating non-thermal technologies — namely ultrasound, microwave and cold plasma — into the extraction step, as well as refining the developed film characteristics, resulting in a versatile and sustainable biopolymer as the final product.”
This collaboration highlights Teagasc’s continued commitment to advancing environmentally sustainable solutions in material science. Rifna adds that although shell waste valorisation for production of biopolymer shows strong potential, the process is not without hurdles. “Escalating production, improving the extraction process, and confirming cost-efficiency are challenges that scientists and industry experts will need to overcome. Nonetheless, this research also opens up greater possibilities for the conception, use and spread of sustainable methodologies.”
Packed with properties
Cellulose, a polysaccharide derived from plant sources, is well known for its polymeric properties and has established numerous applications in the packaging industry for ages. However, less well-known is the world’s second-most abundant polysaccharide, chitin. While chitin is abundantly accessible from sea waste such as crustacean or mollusc shells, it has long been considered a structural molecule devoid of any remarkable biological properties. Fortunately, in the past few years, greater attention has been focused on the chitin present within these shell resources, leading to more comprehensive research into its potential applications.
Rifna explains further: “Chitin, also recognised as poly 2-acetamido-2-deoxy-β-D-glucose, possesses brilliant film-forming properties such as biodegradability, chelate metal ions, non-toxicity, as well as adsorption properties, which give it its novel and robust biopolymer properties for food, biochemical, pharmaceutical and water purification applications. Crucially, the chief properties of the biopolymer nature of chitin are its tensile strength, moisture barrier property, permeability, stability and versatile nature with high molecular weight.
“This biopolymer, developed from shell waste, possesses multi-dimensional benefits, from waste valorisation to inhibiting lipid oxidation, halting microbial proliferation, guaranteeing food safety and — most importantly — being decomposable”.
Shaping the future
All of which means that chitin biopolymer has the ability to be combined into both active and intelligent packaging structures to prolong the expiration period of packaged foods. The production of this biopolymer begins with the extraction of minerals, chiefly calcium carbonate from the shell waste, followed by the deproteinisation and deacetylation process. Numerous extraction techniques, namely chemical, mechanical, and use of non-thermal technologies, have so far been used to extract and isolate this high-value compound. Once isolated, the chitin molecule undergoes thorough processing steps to get shaped into the most robust form for biopolymer synthesis.
Biopolymer production through waste shell valorisation showcases a remarkable combination of technical innovation and ecological responsibility, concludes Rifna.
“By identifying the hidden treasure among these discarded side streams from the ocean, we can pave a path to a more resilient future. As long as the scientific community continues to discover and refine the necessary processes, the effect of shell-obtained biopolymers on the industrial sector can be groundbreaking, pointing us towards a more sustainable tomorrow.”
Funding
This research was funded by Horizon Europe Innovation Action Programme, Grant Agreement No. 101084437.
Contributors
Rifna E. Jerome
Post-doctoral fellow,
Food Research Centre,
Teagasc Ashtown.
Ramesh Babu
School of Chemistry,
Trinity College Dublin.
Brijesh K. Tiwari
Principal Research Officer,
Food Research Centre,
Teagasc Ashtown.
brijesh.tiwari@teagasc.ie
[pic credit] Lisovskaya/istockphoto.com
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