About the project

The ProFôr pre-project investigates the potential of two Norwegian duckweed species (Lemna minor and Spirodela polyrhiza) as sustainable protein ingredients for animal feed. Duckweed can contain 35-40% digestible protein by dry weight when grown under optimal conditions.

The project aims to optimise indoor, year-round duckweed cultivation using nutrient-rich wastewater from land-based fish farming facilities (RAS systems), which currently goes to waste. By manipulating light quality, intensity, and photoperiod, we seek to enhance both biomass production and amino acid profiles specifically tailored for livestock feed requirements.

This approach aims to reduce Norway's dependence on imported protein sources like soybean meal while transforming aquaculture wastewater into a valuable resource, creating a circular economy between blue and green sectors.

• Background

  In 2023, Norway imported 7.7 times more protein ingredients for feed than was produced domestically. Important protein sources such as soybean meal and rapeseed pellets are entirely imported. The growth potential for conventional protein crops is limited due to declining land availability and unsuitable climatic conditions in both the EU and Norway. To reduce import dependency, we must explore alternative sources of digestible proteins and amino acids, as well as implement more efficient cultivation strategies.

  Duckweed is a group of small, free-floating aquatic plants found in calm freshwater environments. Under optimal conditions, duckweed can double its biomass in two days and produce four to five times more protein per hectare than soybeans. This makes it an extremely efficient protein source.

  Land-based smolt farming is an important part of the Norwegian seafood industry. Large-scale recirculating aquaculture systems (RAS) recirculate most of the water through a treatment process, but the clean and nutrient-rich overflow water is currently discharged as wastewater. This continuous overflow water provides a unique opportunity for year-round indoor duckweed production.

• Objectives

  The main objective is to generate knowledge to support year-round indoor biomass production of two Norwegian duckweed species with high protein content for use in animal feed, utilising existing wastewater resources from land-based aquaculture. Specific objectives include investigating 1) optimisation of growth conditions, 2) enhancing amino acid profiles using light, and 3) analysing production predictability across varying RAS conditions.

Participants

NMBU participants

External participants

Felleskjøpet Fôrutvikling AS