Enhancing value of small-sized Baltic herring for human consumption: Techno-economic comparison of fish processing concepts

A conceptual level techno-economic comparison was conducted to assess the production costs for three concepts processing whole fish without gutting or scaling to human nutrition. The assessed processes included enzymatic hydrolysis to produce fish protein hydrolysate, alkaline pH shift process to produce fish protein isolate and high-moisture extrusion processing to produce restructured fish extrudate. The assessment focused on Baltic herring. The results indicated that restructured fish has potential for profitability even at small capacity (100 kg/h fish), with profitability largely depending on the selling price of the product and the cost of the structuring ingredient, pea protein isolate. For fish protein hydrolysate and fish protein isolate production, the break-even capacity was around 1000 kg/h fish, with the selling price of the main product and the fish cost being the most significant cost factors. The economic superiority between these two concepts depended on the price difference of the main products.