Converting under-utilized microalgal co-product into value-added ingredient for cost-viable, fish-free aquafeed for rainbow trout

Project Number
Project Date Range
Funding Agency
National Oceanic and Atmospheric Administration (NOAA)
Focus Area(s)
Sustainable Fisheries and Aquaculture

With growing demand for farmed fish as a more sustainable source of protein for the planet, there is increasing attention to the sustainability of feed used in aquaculture production. Current aquaculture feeds are over-reliant on ocean-derived fishmeal and fish oil rendered from forage fish. Research suggests that at current rates, demand for aquaculture feeds could outstrip supply of forage fish by 2037. In addition, there is a growing need for fishmeal and fish oil from other industries.

In this project, researchers aim to develop a new protein meal by processing under-utilized microalgal co-products that are left over from oil extraction in existing facilities. They will develop a new aquafeed formulae by combining protein-rich microalgal co-product with another oil-rich microalga to fully replace fishmeal and fish oil for rainbow trout feeds. The project will determine: extrusion and enzymatic process of microalgal co-product; levels of nutrients and anti-nutrients in a co-product meal; digestibility and growth; human health-promoting omega-3 in trout flesh; and water pollution consequences and economic evaluation of the experimental feeds.

This project will help improve the sustainability of trout production, while lower the cost of feeding trout and potentially improving the nutrition values of farmed trout. The outcome will directly contribute to more environmentally sound diets with no fishmeal and fish oil, and economically sustainable use of under-utilized resources and will directly benefit aquaculture operations, public hatcheries, microalgae operation, and feed mills. The results will be shared with California Department of Fish and Wildlife, private and public trout facilities, and conferences.

Principal Investigators
profile photo of Pallab Sarker Pallab Sarker
University of California, Santa Cruz (UCSC)