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Optimal utilization of seafood side-streams through the design of new holistic process lines

Periodic Reporting for period 2 - WASEABI (Optimal utilization of seafood side-streams through the design of new holistic process lines)

Reporting period: 2020-11-01 to 2022-04-30

The current exploitation of the aquatic resources is hampered by inefficiency, with up to 70 % ending up as low-value products or waste, which is unsustainable considering the populations growth. With the aim of increasing the utilisation of this currently poorly exploited biomass for higher value purposes, WaSeaBi objectives are:
A. To identify hurdles and bottlenecks that prevent exploitation of seafood side-streams.
B. To develop improved sorting and storage technologies for side-streams to use in house and during transport.
C. To develop tools for supporting decisions for valorisation of side-streams.
D. To develop guidelines for optimal logistics throughout the supply chain.
E. To offer more high-quality side-streams to biobased industries.
F. To develop/implement innovative processes for the production of new ingredients from high-quality side-streams.
G. Development of biorefinery concepts for the valorisation of side-streams.
H. Demonstration of the potential for integrating the developed concepts into the current industrial landscape of the participating industries.
I. Quantify the environmental, economic and social impacts of the studied value chains, processes and products in order to guide the consortium in the development of feasible solutions though preliminary life cycle assessments.
J. To maximize the influence of the project results both during and after the project by targeting project partners, enterprises within the fisheries industry, knowledge institutions, innovation networks/clusters, associations, the scientific community, as well as policy makers and regulators at a regional and European level.
With reference to the above objectives the following work has been carried out. No reference means that work has just been initiated.

A. To identify the hurdles and bottlenecks, which prevents exploitation of seafood side-streams, an industry and a consumer survey have been carried out. The main hurdles and bottlenecks identified in the industry are the lack of technology, space and personnel, & the lack of market knowledge regarding new products from side-streams. It was found that the consumers’ barriers and motives are the eating quality and that consumers want to be informed about the origin and environmental impact of the ingredients, raw material and food products. In addition, a clean label is a reason for the consumer to buy the product.
B. Currently, herring side-streams are not sorted into different fractions such as guts, heads, tails and frames, which makes it impossible to use the different types of side-streams for purposes other than fish meal and oil. To solve this, a filleting line for sorting of herring solid side-streams into 4 different fractions has been installed. Detailed data on crude composition, fatty acid and amino acid compositions, vitamins B12 and D, and minerals have been obtained from these fractions, pointing to a very nutritious nature. Several promising preservation strategies have been developed based on new cooling/handling, and treatments with acidification or antioxidants. For solid herring and cod side-streams, dipping them in solutions from the antioxidant mixture Duralox-MANC or from a rosemary extract have extensively prolonged their storage stability on ice and during frozen storage. A questionnaire for fishing vessels in Spain and Denmark has revealed that installation of new storage facilities on board fishing vessels for landing of unwanted and unavoidable catch are not necessary because such unwanted catches have been reduced to almost nothing.
C. One of the decision tools developed is an app, which guides the seafood producer on what to do with their side-stream based on the information that is entered about the raw material, the side-stream and the processes to which they were exposed. A first version has been developed and has been further enhanced with new features to include environmental and economic assessment results. Furthermore, the development of a bias correction tool has been started, which will ensure the best possible evaluation of the data entered in the decision tool.
D. A so-called Value Chain Navigator has been drafted and will be validated in the next period. This navigator will identify the optimal logistics and processing technologies for handling the side-streams throughout the value chain.
E. The installation of the sorting system for herring side-streams has increased the number of herring available side-streams from 1 to 4. The development of the storage solutions described in B has increased the quality and shelf-life of the solid side-streams from cod, herring and salmon.
F. Different approaches to develop new ingredients from seafood side-streams have been used:
• Different flocculation techniques to concentrate proteins have been tested on liquid side-streams of herring, cod and mussel cooking waters with recovery levels up to 96 % depending on the type of liquid side-stream and flocculation technique used.
• Several concentration technologies on the mussel cooking and cod process waters to generate savoury ingredients, to reduce the salt content or to concentrate proteins and phosphorous for reuse in the cod filleting process.
• Work has been done to optimize the pH-shift technology for recovery of protein in liquid and solid side-streams of cod and herring processing. A combination of cod head and frame for protein isolation is optimal to obtain the best gel forming properties. For herring, the most promising fraction is the frame. For herring, the use of frames pre-dipped in antioxidant solution has resulted in highly stable protein ingredients.
• Technologies to produce bioactive peptides with antioxidant or antimicrobial activity, and savoury peptides (rich in glutamic acid) from salmon, herring, mussel and cod side-streams have been optimized. By applying enzymatic hydrolysis using different enzyme mixtures, bioactive or savoury peptides can be obtained. Good results on peptides yields have been obtained, but low or no-bioactivity was found. Savoury hydrolysates with high content of glutamic acid and umami flavour were successfully obtained. The hydrolysis process resulting in savoury ingredients also provided a mineral fraction.
G. The most promising value chains based on outcomes from the work described above have been selected for upscaling.
I. A preliminary evaluation of the potential environmental impacts of two value chains (i.e. pH shift and membrane concentration) has been carried out, as well as several benchmark scenarios to valorise fish/shellfish side-streams have been assessed from an environmental perspective.
J. WaSeaBi has been disseminated through the project website, 6 WaSeaBi newsletters, over 150 posts on WaSeaBi’s social media channels, 5 press releases with high media pick-ups, 50 dissemination events and 7 scientific publications.
• A reconstructed filleting line with sorting capacity plus an integrated antioxidant dipping technology has been implemented for herring side-streams at Sweden Pelagic. The muscle remaining on the frame can easily be further separated, e.g. with mechanic meat/bone separation or pH-shift processing.
• A technology to produce savoury ingredients from cod, hake and salmon side-streams has been developed. The technology can most likely be used for other fish side-streams too.