Better utilization of deceased farmed fish

Background

Fish that die in aquaculture, “category 2 fish,” are discarded and mostly go to silage – a low-cost product typically used in fuel and fertilizers. Although this fish cannot be used for food, it is a rich source of proteins and oils, among other things, and can become a valuable resource if processed properly.

With the aquaculture industry growing, it’s important to implement measures to better utilize category 2 fish. By breaking down the raw material using enzymatic hydrolysis, valuable resources can be preserved and used for various purposes.

Goals

In this project we will test potential applications of all hydrolysis fractions in biorefinery. The aim is to determine:

1. whether resources from this fish can be used in the production of epoxy-based coatings, sustainable aviation fuel, biodegradable polymers (chitosan), and organic acids (succinic and citric acid)
2. whether different fractions from hydrolysis are suitable as fertilizer

What we do

Researchers at Nofima, NMBU, and SINTEF collaborate to:

• develop methods for efficient extraction and separation of nutrients from category 2 fish
• test if it can be used as feed for microbial fermentation, and as fertilizer
• produce various hydrolysates under varying process conditions
• chemically characterize hydrolysates, oils, and residues
• formulate protein hydrolysates as fermentation feed
• test hydrolysis residues as fertilizer

We use food-grade salmon for the initial experiments and will conduct trials with category 2 fish in a later phase of the project.

Worth knowing

Contact person

Josipa Matić

Scientist
+47 64 97 04 40