Demand for fish is steadily increasing and the supply of farmed fish must therefore be increased in order to maintain a stable supply and reduce the pressure on fishing. Fishmeal is the predominant source of protein in fish feed, but the production of the meal has shrunk as the utilization of pelagic fish in more valuable products has increased due to better fishing technology and better cooling of the raw material.
At Matís, dr. Ragnar Jóhannsson, project manager, has been working on various projects aimed at finding raw materials other than fishmeal for aquaculture and utilizing unused raw materials. Waste from cellulose factories in Sweden and the cultivation of biomass in geothermal gases from the Hellisheidi Geothermal Power Plant are possibilities that have been explored.
Ragnar has worked with Swedish companies in the production of Single Cell Protein (SCP) from sidestreams from the forest industry. The main goal is to develop a product that replaces fishmeal. It was necessary to find out which microorganisms were most suitable and which sidestreams in cellulose and paper production were best suited for this production. The protein mass is dried and mixed with other raw materials to make aquaculture feed. This feed has been tried in tilapia farming with good results and is currently being developed for char farming.
Another method that has been tried in feed production is to use hydrogen sulphide from the Hellisheidi power plant as an energy source in the cultivation of microbial biomass. The microorganisms grow rapidly on hydrogen sulphide, are then dried and added to aquaculture feed. This project was recently completed after two years of development work, but further research is needed to maximize results.
For further information Ragnar at Matís.