Creating value
2013
nofima.no
22
Financed by:
Rubin, Norwegian
Seafood Research
Fund
Partners:
The Norwegian Seafood Federa-
tion, Scanbio, Hordafor, Akvaren,
the Norwegian Veterinary Institute
and NFSA
This is the end product of the new method and may be used as biogas and fertilizer, as well as a feed for dog teams.
photo: Jon-Are Berg-Jacobsen © nofima
This method can benefit the entire aquaculture industry.
In 2012, approximately 1,2 million tonnes of farmed
salmon were produced in Norway. Around 5% or 60,000–
80,000 tonnes of the fish die in the cages. The fish are
collected daily and preserved on site by grinding and
mixing them with formic acid. The fish may have died of
various causes, including disease.
Dead fish basically have the same nutritional content
as harvested fish, but the risk of the fish containing vari-
ous pathogens is far greater. Pursuant to current regula-
tions, material from dead fish must be treated with high
pressure sterilisation, which is highly energy-intensive
and harmful to the products.
“We have carried out several projects to map how
much heat is needed to provide adequate killing of
relevant pathogens in fish preserved in formic acid,” says
Senior Scientist Halvor Nygaard from Biolab at Nofima.
Salmonella and Clostridium perfringens spores were
among the pathogenic bacteria studied. The IPN virus,
which is the most heat-resistant among known patho-
gens in fish, has also been investigated. New knowledge
about the heat resistance of the IPN virus has made it
possible to establish process requirements that ensure
safe products.
The new processing method is based on formic acid
treatment at pH 4 stored for 24 hours followed by heat
treatment at 85 °C for 25 minutes. This method has
been tested in industry scale at Scanbio in Bjugn, and
is now about to be approved by the EU, after gaining a
positive risk assessment from the European Food Safety
Authority (EFSA).
A new processing method for dead fish from the aquaculture industry
leads to reduced energy consumption and products with more uses.
New method kills pathogens
