Fish meal and fish oil Fish meal is typically a dark brown powder, but there are numerous variations based on fish species, particle size, lipid- and moisture-content etc. Fatty acids constitute the liquid component of fish oil. Fish oils are typically rich in PUFAs, which are required to maintain fluidity in membranes in cold environments. Most of the fish meal and oil are produced by the wet pressing method with these steps: cooking, which coagulates protein and releases bound water and oil, pressing, decanting, and centrifuging. The pressing step compresses unbound particles (primarily protein and bones), the decanting removes sludge from the liquid phase (press liquor) and centrifugal separation separate oil and stickwater. After the stickwater has been concentrated, it is combined with the press cake and dried, resulting in two distinct products: fish oil and meal (Xxxxxxxxx et al., 2019). 100 kg of raw material produce approximately 20 kg of fish meal and between 3 and 6 kg fish oil (Xxxxxxxxx et al., 2019). Typical fish meal contains 64 to 67 % crude protein, up to 12 % fat, and 10 to 20 % ash. In addition to a higher protein content of 68 to 72 %, specialty products typically have a lower biogenic amine content, which reflects the freshness of the product. The two main fish meal formulations used today in Norwegian aquaculture feed production are NorSeaMink and the higher quality Norse-LT 94, both representative for the world commodity market (Xxxxxxxxx et al., 2019). Typically, the sales values of fish oil are determined for oils containing 2-2.5 % free fatty acid, 3.5 % unsaponifiable material, and 0.3 % impurities (Iñarra et al., 2020). When these thresholds are exceeded, the price is negatively affected. Other factors that may have a negative effect on price include odour and dark colour (Xxxxxxxxxx et al., 2009). Initial experiments on the creation of fish meal with mesopelagic biomass has been performed as part of the MEESO project. Additionally, we have collected rudimentary data from other partners with previous knowledge on the subject. The biochemical parameters collected on Xxxxxxx’x pearlside is presented in Table 2. For clarity of reading, the water content has been adjusted mathematically to 10 % regardless of actual content. Table 2 Biochemical parameters collected on Xxxxxxx’x pearlside Protein (wt %) water- soluble protein (wt %) fat (wt %) ash (wt %) Adjusted water content (10 %) Northern Sea (Norway) 62.8 29.7 15.7 13.3 10 Northern Sea (Iceland) 6...
Fish meal and fish oil The techno-economic feasibility of the production of fish meal and oil is based on the following assumptions: As there is no limitation from the market to the production due to the increasing demand from the aquaculture feed sector, the quantity to be processed depends on the recommended quota of the biomass. This is also investigated in the MEESO project. In a previous study conducted by the Institute of Marine Research (IMR) in the Icelandic fishery from 2009 to 2013, it was recommended a precautionary exploitation of the stock not exceeding 30,000 tonnes in that area. However, catches were very unreliable, from 46,000 tonnes in 2009 to none in 2013. Due to the estimated levels of organic contaminants found in fish oil in the samples from the Norwegian Fjords (Xxxxx et al., 2020), it might not be suitable for food or feed unless refining and cleaning methods are employed. However, maximum levels for animal feed were not exceeded. The levels of organic contaminants found after processing of biomass from the North Atlantic were below the maximum levels in feed and lower than in analysed commercial fish oil samples (Berntssen et al.2021). The concentrations in fish meal were also below the maximum levels. Applying a feed-to-fillet transfer model for Atlantic salmon, it was estimated that processed mesopelagic aquafeed ingredients would reduce the level of dioxins and PCBs by ~30%. Because of rapid degradation of these small sized fishes, on board processing may be advisable, and a suitable preserving method should be implemented on board. Maximum time to preserve the fish before landing must be established. Ensilaging of the fish with formic acid on board the vessel is a potential method for preserving. Existing Basque fleets might not be suitable for implementing an onboard processing plant, and the investment for that is high. The low price of the mesopelagic resource, estimated in 0.2 - 0.7 €/kg calls into question the recovery of such an investment. Therefore, the study on the economic feasibility must be done in two scenarios:
