A pioneering research project at the University of Borås has demonstrated how organic waste—particularly food waste and animal manure—can be transformed into high-value protein sources for animal feed. Conducted within the university’s Resource Recovery programme, the work highlights a promising pathway for circular, sustainable livestock nutrition.
In her doctoral research, Clarisse Uwineza explored how waste streams can be converted into volatile fatty acids (VFAs) through anaerobic digestion. These VFAs then serve as a nutrient-rich substrate for cultivating Aspergillus oryzae, a fungus that produces a biomass high in protein, minerals, and dietary fibre—and is easily digestible for livestock.
Uwineza’s interest in biotechnology and sustainable waste management shaped the project, which addresses one of agriculture’s growing environmental challenges: the large volume of organic residues generated from food systems. Using controlled anaerobic digestion, waste is broken down in oxygen-free conditions, yielding VFAs as well as nitrogen and mineral nutrients. These support the growth of fungal biomass that could replace conventional protein sources such as soybean meal and fishmeal.
“My work shows that organic residues can serve as valuable raw material for sustainable protein production, helping to close the loop in a circular economy,”
— Clarisse Uwineza
One of her notable findings was the fungus’s surprisingly strong growth on waste-derived VFAs—even though these acids can be toxic at high concentrations. By carefully regulating the addition of VFAs, she developed a method that ensures safe, gradual fungal growth with higher yields and improved product quality.
Beyond animal feed, this fungal biomass shows potential for use in bio-based materials, including biodegradable plastics and leather alternatives. The research demonstrates significant opportunities to reduce emissions, optimise resource use, and support the rise of a circular bioeconomy.
The project contributes directly to several UN Sustainable Development Goals, including SDG 12 (Responsible Consumption and Production), SDG 13 (Climate Action), and SDG 2 (Zero Hunger).
Source: National Hog Farmer
