Protein and high value raw materials from grass: €9m project kicks off across Ireland and Denmark

Two green biorefinery and anaerobic digestion demonstration sites in Ireland and Denmark will optimize the conversion of grasses, clover and green biomass residues sourced from local farms, into value-added products such as human and animal grade protein, bio-based food packaging, flavors, anti-microbials, fertilizer and energy, in collaboration with upstream research and industrial sites in Netherlands, Ireland, Denmark and Poland.

The project, Rural BioReFarmeries, is funded under the Circular Bio-based Europe Joint Undertaking (CBE JU)​​ to the tune of €8.7m (US$9.45m). The aim is the deployment of green biorefineries across grassland regions of Europe.

By improving the efficiency and circularity of European grasslands, it is possible to produce, not only forage, but also food, high value materials and energy, remarks project coordinator James Gaffey, co-director, CircBio, MTU, said: “Grassland valorization and emerging grass-based value chains represent a major strategic opportunity for the EU bioeconomy.”

Building on previous projects ​

The latest initiative builds on a grass biorefinery project run over two years in Ireland that was completed in 2021​​. Several co-products were produced that showed great promise for dairy and pig diets. That scheme was born out of the idea of establishing a bottom up, multi-actor approach to addressing challenges in the Irish agricultural sector, combining consortia which include farmers as well as researchers to tackle issues.

Called Biorefinery Glas​​, it involved a consortium including MTU, University College Dublin (UCD), which ran dairy cow trials, the Carbery cooperative, which assessed the biorefineries on farm and the Barryroe cooperative, which evaluated a co-product in pig feed. Wageningen University-spinout, GRASSA, provided the biorefining technology.

Gaffey reports significant progress stemming from that work. “Due to the positive results, the Irish Department of Agriculture decided to provide funding to help us develop a demonstration plant. They've allocated around €3m, with additional funding from Enterprise Ireland.”

The idea is to locate the demonstration scale biorefinery facility along with an anaerobic digestion unit at Farm Zero C​​, which is a collaborative effort between Carbery, BiOrbic and others to create a climate-neutral, economically viable dairy farm.

Addressing commercialization challenges​

Under Rural BioReFarmeries, this demo plant will focus on addressing bottlenecks identified in previous work to facilitate commercialization. Although some grass derived protein plants in Denmark​​ have already been commercialized, there are still challenges to overcome, explains Gaffey.

“We're collaborating closely with Denmark, leveraging their advanced experience in implementing such technologies.”

The Danish demo site for the Rural BioReFarmeries will be located at the Aarhus University Green Biorefinery Demonstration Platform in Viborg.

One significant challenge the team has encountered, both in Ireland and Denmark, is the economic feasibility of protein production, especially for the animal feed market.

“In Denmark, the focus is on organic protein, which remains economically challenging even there. Hence, we're exploring higher-value products and ways to enhance the process.

“Additionally, fresh grass, a primary feedstock, is only available for about eight months a year, complicating the business case for year-round operations. To address this, we're investigating ways to improve the grass itself, such as through multi-species grass swards, and exploring other feedstocks like sugar beet leaves and silage. This diversification aims to ensure a year-round supply and improve sustainability.

“Moreover, we recognize that some commercial plants still rely heavily on subsidies, particularly for biogas, which is a significant part of the economic model in places like Denmark. Addressing these economic dependencies is crucial for the long-term viability and wider adoption of green biorefineries,” he tells FeedNavigator.

Biorefining activities start on the farm

Rural BioReFarmeries will test a decentralized approach where biorefining activities start on the farm. This method combines the smart production and harvesting of sustainable local biomass with decentralized processing close to the farm. The biorefinery co-products will then be transferred to relevant downstream sites for further product development.

“We explored ways to engage a variety of industry players because, within this CBE JU demo project, there is a significant need to transition from the lab and pilot level to a demonstration level. It's not sufficient to simply identify promising ingredients; we need to develop prototype products and test them with industry,” continues Gaffey.

ACCRES in Lelystad, Wageningen University’s trial and development location for sustainable energy and green raw materials is involved, for example, as researchers there are converting fibers from grass into packaging.

The project aims to create new value chains, replicable business models, and training activities that can be implemented across rural regions of Europe, an aspect that will be led by Danish research and innovation organization, SEGES, among other partners. 

Value-added products   ​

“One of the novelties in our project is the implementation of a novel anaerobic digestion system for processing the brown juice left after grass protein and fiber extraction. Typically, this brown juice is combined with press cake for biogas production. However, our system will produce volatile fatty acids (VFAs) in addition to biogas and digestate,” says Gaffey.

The Polish, Irish and Danish partners will be involved in assessing the VFAs for their potential as valuable products.

“For example, butyric acid, one of our target VFAs, can be used as a flavor ingredient. We plan to test these VFAs as flavors in collaboration with our agri-food industry partner, Carbery. Additionally, we will explore the antimicrobial properties of VFAs for use in food packaging to extend the shelf life of meat and reduce food waste. Another potential application of VFAs, which we will investigate, is as an additive in pig diets to reduce the use of zinc oxide, which may have beneficial health effects and reduce the need for antibiotics in pigs.”

Furthermore, the project is looking to produce functional proteins from grass.

“Our previous work focused on using protein concentrate as feed for pigs or chickens. In this project, we will also explore the separation of the functional protein, Rubisco, from the protein concentrate and test its functional properties, such as emulsifying, water-holding capacity, and gelling. We will then develop prototype products, like powdered beverages or protein bars, to assess their viability.

“Our goal is to balance these efforts, not shifting entirely to food production but finding ways to enhance economic viability of the protein. Even if only 10-15% of the protein concentrate could be used as a high-value food ingredient, it would significantly improve the project's economics.”

LCA and biodiversity assessments ​

The project will also involve both life cycle and biodiversity impact assessments.

"We submitted a paper a few days ago on research undertaken by Irish partners in collaboration with Aarhus University, that examines the sustainability of different grass biorefinery processing methods and compares the environmental footprint of grass protein with soybean meal.

"Our findings indicate that the footprint of grass protein is about five times lower than that of soybean meal depending on the feedstock and process parameters used, which aligns with similar results from other studies. The sustainability impacts of this model, including environmental, social and economic sustainability, along with potential impacts on biodiversity will be further evaluated within the Rural BioReFarmeries project.”