Hanne Jorun Sixten: Completing a PhD on marine side-streams in aquafeed 

In BioMar, we have scientists who are advancing our understanding of fish nutrition and aquaculture. Today, we share the journey of Hanne Jorun Sixten, who recently completed her industrial PhD in collaboration with the University of Bergen, Nofima, and BioMar. 

Hanne started her PhD in July 2021, focusing on how marine side-streams can be used more effectively in aquafeeds. In November 2025, she submitted her thesis, and on the 16th of April 2026, she successfully defended her work. 

Hanne’s work has been focused on one clear principle: fish require nutrients, not ingredients. From this perspective, her research examined how circular raw materials, such as whitefish and krill side-streams, can contribute to feed performance beyond their basic nutritional value. 

Across three scientific papers, her findings show that bioactive components can support comparable or improved performance in Atlantic salmon, while also influencing key biological processes. This includes how fish regulate feed intake, how nutrients are utilized, or how fish respond to stress under challenging conditions. 

Hanne’s work also highlights that feed formulation is about understanding how specific components interact with fish physiology and the nutritional requirements. Thanks to this link between ingredient functionality and biological responses, the research provides valuable insight into how sustainable, high performing aquafeeds can be developed more effectively. 

Completing an industrial PhD requires balancing scientific research with industry relevance. Hanne’s work reflects this, contributing knowledge that supports the development of aquafeeds while advancing our understanding of how circular ingredients can be used in practice. Congratulations to Dr. Hanne Jorun Sixten!