How PROTEIN4IMPACT Produces Proteins from Alternative Sources

As the global demand for sustainable protein continues to grow, researchers are exploring new ways to produce high-quality proteins while reducing pressure on natural resources. Alternative protein sources such as fungi, algae, insects, food industry by-products and aquaculture side streams are being explored in PROTEIN4IMPACT. One of the project’s main objectives is to develop novel foods based on these resources. Before these proteins can be incorporated into food products, however, they first need to be efficiently produced or recovered using technologies tailored to each type of raw material.

Because every feedstock has unique characteristics, there is no single processing method suitable for all of them. PROTEIN4IMPACT therefore investigates a range of innovative technologies tailored to different protein sources. For example, fungal biomass is produced through fermentation in airlift bioreactors. Brewer’s spent grain (BSG), one of the largest by-products of the brewing industry, is processed using extrusion technologies, whereas proteins from fish processing side streams are recovered using microwave-assisted extraction (MAE). After extraction, fish residues still have high carbon and nutrient content, which can be upgraded into bioenergy and microbial proteins by coupling anaerobic digestion to the cultivation of hydrogen oxidizing bacteria. Additional unconventional resources are also being investigated as the project seeks the most efficient and sustainable production routes.

Airlift bioreactor (UMINHO).

Laboratory setting for hydrogen-oxidising bacteria cultivation (DTU Sustain).

Microwave-assisted protein extraction (CNR).

The first results already demonstrate the potential of these approaches. Brewer’s spent proved to be an excellent substrate for fungal growth and mycoprotein production and was selected for subsequent cultivation of fungal biomass in an airlift bioreactor. Research is also exploring how agricultural by-products such as banana residues, brewer’s spent grain and cocoa shells can be used as feed for protein-rich insects, including Tenebrio molitor and Alphitobius diaperinus, potentially improving both their nutritional composition and the overall sustainability of insect production.

Another promising outcome comes from aquaculture side streams. Using microwave-assisted extraction, researchers have been able to recover proteins up to 30 times faster than with conventional extraction methods, demonstrating how innovative processing technologies can improve both efficiency and resource utilisation.

As the project progresses, these technologies will continue to be refined and combined with further research on food formulation, safety and consumer acceptance. Together, they will help transform underutilised biological resources into sustainable protein ingredients for the foods of the future.