Coupling the benefits of grassland crops and green biorefining to produce protein, materials and services for the green transition

Abstract

Compared with annual grain and seed crops, perennial grassland has significantly lower losses of nutrients and low pesticide requirements, whilst also supporting soil carbon build‐up. Until now grassland crops have almost exclusively been fed to ruminants and horses. Our experiments on biorefining forages have produced protein of a quality equal to soybean meal. Forage crops can deliver high yields of biomass as well as protein with a well‐balanced amino acid profile. In grass crops from unfertilised permanent grassland, focus has to be on the fibre part of the grass due to a low protein yield. With current techniques we have recovered up to 40% of the forage protein into a protein concentrate with around 50% protein. In addition, a fibre fraction containing 15%–18% protein of dry matter can be produced and used as ruminant feed, bioenergy, or further biorefined into chemical building blocks or bio‐materials. Our feeding experiments have shown that biorefined grassland protein can provide a substitute for soybean meal for poultry and pigs without negative effects on animal performance. The first industrial scale biorefineries on green biomass for feed and bioenergy are now established in Denmark, although more research is needed in order to evaluate protein quality for both feed and food applications. In addition, a full EFSA approval has to be obtained for the application for food. The green biorefinery concept opens new markets for grassland and opportunities for increasing the grassland area to obtain associated ecosystem services.

Biochemical Assessment of Solid-State Fermented Elephant Grass and its Potential Incorporation in Broiler's Diets

“…Therefore, the diets containing these forages were able to provide the necessary nutrients for the birds to maintain their weight, resulting in no significant difference compared to the control diet. Overall, the use of forages in broiler feeding can have economic benefits, as they can reduce the volume and cost of feed used in production (Jørgensen et al, 2022). Additionally, the nutritional quality of the forages can contribute to maintaining weight and improving the overall health of the birds.…”

Waste reintroduced in the kitchen: life cycles inventories of representative waste-to-nutrition pathways

“…Finally, as designed, the GB LCI model is only suitable to assess GB as an alternative management practice for green residues. Indeed, GB is also part of the basket of strategies aiming to repurpose available land in a context of developing grasslands-based bioeconomies (Jørgensen et al, 2022), and the present model needs to be complemented (e.g. re ned technological parameter ranges, spatio-temporal feedstock availability, land use change and agronomic practices accounting, etc.)…”

Forage type and additive effects on fermentation quality and biorefinery performance of silages

“…The focus of the current research was to evaluate how the ensiling process manipulated by additive use affected the biorefinery outputs of the different silage batches. Most of the biorefinery development has concentrated on using fresh grass (Jørgensen et al, 2022), but as a stable year-around available feedstock, ensiled biomass would provide benefits, so that studying also silages is justified (Rinne, 2024). There are also indications that ensiling might benefit e.g., liquid-solid separation (Ayanfe et al, 2023), but direct comparisons of fresh and ensiled materials are scarce.…”