Towards a new generation sustainable seafood products–a cross-process approach (CROSS)

Research Project, 2016 – 2023

Despite steadily increasing demand for seafood, massive amounts of prime fish/shellfish muscle is wasted or used in feed for fur animals, aquaculture and pets. This is muscle stuck to bones and shells or dissolved into process waters resulting from filleting and processing operations. The poor upgrading of such side-streams, especially in Sweden, is explained by a lack of suitable isolation technology, stabilizing procedures, tradition and limited side-stream volumes for individual seafood processors. In CROSS, the aim is to explore technologies and product concepts paving the way for new sustainable convenience seafood products from challenging marine muscle sources. Application of the pH-shift protein isolation process (i.e. pH-driven protein solubilization followed by isoelectric precipitation) to fish and shellfish side streams will be central, but with the major innovation that solid and liquid side streams from different species will be crossprocessed with each other, and also with other raw materials like seaweed and agricultural by-products. This development will help reach a critical raw material volume, stabilize the sensitive marine lipid/proteins against oxidation, create new flavors/textures/colors and render the process more scalable and sustainable. To transform the cross-protein isolates into attractive textured food products, 3D-printing will be added as an innovative formulation tool. Through six work packages, we will: (i) identify the most promising combinations of fish/shellfish/seaweed/plant-derived raw materials to use for proof of concepts, (ii) determine protein yields, isolate composition and color when subjecting the selected combinations to known pH-shift processing protocols, (iii) investigate how antioxidants in cross-processing materials can limit lipid/protein oxidation, (iv) investigate how polysaccharides and tannins in the cross-processing materials can aid in protein  precipitation, and elucidate the feasibility of connecting pH-shift processing to 3D-printing, (v) investigate the sensory characteristics of model products and (vi) evaluate the environmental impact of a new generation pH-shift processing; specifically the combining different raw materials and recycling of existing seafood process waters. Apart from new process and product concepts allowing a more complete utilization of food resources we have at hand, project results will stimulate industrial symbiosis, and conversion from a linear to a circular economy.