Project Year 2015
Low drip loss for salmon
Fish is sold by the kilo. But when stored, fish loses weight. The money literally drips off the fish.
However, research concludes that the seafood industry already does what is best to prevent drip loss in salmon.
How much loss can one expect, and what affects fluid loss in salmon? Can anything be done to minimize drip loss? These issues have now been thoroughly documented by researchers at the Nofima food research institute, in collaboration with Sør-Trøndelag University College and Marine Harvest’s slaughterhouses at Hjelmeland and Hitra.
Each percentage of weight lost means a lower sale value. When sellers and buyers of large consignments of fish agree on the price, the so-called drip loss is an important factor to take into account.
A number of variables were tested in order to document what results in the least fluid loss. Researchers have compared whole fish with fillets, fish from farms in the north with fish from farms in the south, fish slaughtered during the spring with fish slaughtered in the autumn, and fish that was filleted pre-rigor and fish filleted post-rigor.
“One has to take into account a loss of 1-2%. But when all is said and done, it is the storage time which is decisive. The shorter the storage time, the less fluid loss,” says Nofima researcher Bjørn Tore Rotabakk, who headed the research experiments.
Fillets lose the least fluid at cooler temperatures, and it is thus best to store fillets on ice, if the weight is to be maintained as high as possible.
Pre-rigor fillets have a higher drip loss than post-rigor fillets, but this is because post-rigor fillets are filleted at a later stage and that whole fish have far less drip loss than fillet. On the other hand, post-rigor fillets have other challenges with splitting and texture.
“The best results coincide with fish that have undergone what is common practice in the seafood industry. We can therefore say that much of what is currently done is done in the best way,” Rotabakk says.
IN COOPERATION WITH:
Marine Harvest and the Programme for Food Technology at Sør-Trøndelag University College
The Research Council of Norway and Marine Harvest