Processing and storage of mussels: mussels to feed through fly larvae

The process line developed in the project is shown in Figure 1, which illustrates the different steps from harvest of Baltic Sea blue mussels to fish feed through fly larvae composting. This report describes the process line from Pre-process treatment (No 3.) to Post-process treatment (No 7.). The most crucial part of the process line is the fly larvae compost, as this involves living organisms that must be treated in certain ways to survive. SLU has long experiences of this and has operated fly larvae composting with municipal source separated organic waste since 2011. Several tests with blue mussels have been done in this project, where the experiences from the use of organic waste is used as a reference. Other parts of the process line - ensilage (optional); crushing of mussels before feeding them to the fly larvae; separation of fly larvae, shells and droppings and finally drying of fly larvae – are more straight forward and dependent on the technical equipment that are selected. Thus, other techniques, than those selected in this project, could be used depending on e.g. experiences, availability, local circumstances and economy.