Aquaculture is expanding rapidly, but much of the sector remains tied to fishmeal: an ingredient made from wild-caught fish such as anchovies. Researchers at the University of Queensland say a new fermentation process could offer an alternative by turning gases generated from organic waste into a protein-rich feed ingredient.
The approach is intended to reduce aquaculture’s dependence on harvesting small wild fish while also putting carbon from waste streams to use. It is still a production technology under development, rather than a demonstrated replacement across commercial fish farms, but the research team says it has secured a patent for the conversion process.
From organic waste to feed ingredient
The process begins with anaerobic digestion, in which microorganisms break down organic material without oxygen. That produces biogas containing methane and carbon dioxide. Instead of treating those gases solely as waste outputs, the University of Queensland team uses them as inputs for fermentation.
In the fermentation stage, the gases support the growth of protein-rich cells. Once collected and processed, those cells become an ingredient known as single-cell protein. The researchers say the resulting material has nutritional properties similar to fishmeal and could be used as a supplement or substitute in fish feed.
Dr. Lars Puiman of the university’s Australian Institute for Bioengineering and Nanotechnology said the work is aimed at a longstanding supply-chain problem. Fish farming has traditionally relied on fishmeal made from large catches of small fish, a practice that can put pressure on marine populations and create emissions-intensive supply chains.
The proposed system changes the feedstock rather than merely seeking a more efficient way to make conventional fishmeal. Its central idea is to capture carbon already present in organic waste, convert it through biogas and fermentation, and return it to the food-production system in the form of feed.
Why fishmeal alternatives matter
Aquaculture has become one of the fastest-growing food-production sectors. The University of Queensland researchers note that farmed seafood is estimated to account for about 62% of global seafood production by 2030. That growth raises the stakes for ingredients used to feed farmed fish.
Fishmeal has long been valued as a concentrated source of protein and nutrients, but its supply is linked to wild fisheries. When feed demand grows, reliance on those fisheries can add to concerns about overfishing, depleted fish populations and the resilience of marine ecosystems.
A feed ingredient made from organic waste would not automatically solve all of those challenges. It would need to meet nutritional, safety, economic and manufacturing requirements at scale. But it could give producers another source of protein and reduce exposure to a supply chain that starts with wild-caught fish.
For the researchers, the prospect is not limited to one type of waste stream or one aquaculture product. The value lies in coupling waste management with feed production: gases released as organic material breaks down become a resource for growing a new product.
A circular-production model
The technology uses methane and carbon dioxide produced during anaerobic digestion, rather than adding a new fossil-based carbon input to the process described by the university. That makes the project an example of a circular-production model, in which a waste-derived material is used as the basis for a new industrial input.
Dr. James Heffernan, also of the Australian Institute for Bioengineering and Nanotechnology, said the same production concept could potentially be expanded beyond aquaculture. In addition to sustainable animal-feed alternatives, the team sees possible applications in soil fertilizers.
That flexibility could matter because a commercial facility designed to process waste and generate biogas may have multiple potential output markets. The immediate focus, however, is fish feed. The team describes the single-cell protein as a nutritious ingredient with properties comparable to fishmeal, positioning it as part of broader efforts to move aquaculture away from conventional fishmeal dependence.
What comes next
The announcement does not specify commercial production volumes, named aquaculture partners or a timetable for deployment. It does, however, establish that the researchers have protected the biogas-conversion process with a patent and are presenting it as a platform that can support future feed and fertilizer products.
For aquaculture companies, the practical questions will be whether the ingredient can be produced reliably at sufficient volume, how it performs in feed formulations and whether it can compete economically with existing options. Those questions are central to any shift in an industry that needs large, dependable supplies of feed.
Even so, the research points to a different way of framing aquaculture’s feed challenge. Instead of seeing organic waste only as something to dispose of, the process treats it as a source of gases that can be transformed into a high-protein material. If it can be scaled, that could help make the growth of farmed seafood less dependent on wild fish stocks.
This article is based on reporting by Phys.org. Read the original article.
Originally published on phys.org
