Testing of water-filled receiving bins on board M.Tr Kongsfjord

Summary

To improve the quality of trawl-caught Atlantic cod, Havfisk Ltd designed and constructed a new trawler in 2018. The goal was to keep the catch alive until it was slaughtered. Nofima was asked to contribute with knowledge about live storage and muscle quality of cod. Two separate research trials were carried out, in October 2020 and 2021. During the first trial, due to low pump-capacity, a fluctuation in the numbers of cod in the tanks and a high mortality rate (<90%), it was not possible to conclude if the distribution of water through a flat or a tilted perforated foundation sheet, influenced the result. For the second trial, the pump-capacity was improved, but the mortality rate was still high (<80%). After 5 hours of live storage, there was an increase in the fish blood pH (7,1 to 7,5). This indicates that live cod can be restituted. However, the results also show that the redness in the fish muscle rapidly increased during the first hours of live storage and remained high through 5 hours of live storage. Furthermore, bleeding trials were also done, showing that bloodspots in the fillets were reduced when fish was bled before mechanical gutting.