Special Edition: Dairy feed trends
Ireland: Project looks to extract high value products from grass
The Biorefinery Glas project, which runs until February 2021, sees IT Tralee partner with University College Dublin, the Carbery and Barryroe Co-operatives and Wageningen University-spinout GRASSA BV, which is focused on the development of biorefining technologies.
The idea is to use small-scale biorefineries to convert freshly harvested grass into a range of products, including; an optimized cattle feed fiber, a non-GMO protein concentrate feed for monogastrics, a high-value sugar stream of fructo-oligosaccharides and a grass whey for fertilizer or bioenergy applications.
The partners will demonstrate a small-scale mobile biorefinery on multiple farms in the South West of Ireland, and will support farmers in evaluating opportunities to diversify into the bioeconomy.
“The Irish Department of Agriculture, through the EIP-Agri initiative, is trying to adopt a bottom up, multi-actor approach to addressing challenges in the agricultural sector, combining consortia which include farmers as well as researchers to tackle issues, that is kind of what brought the group together,” James Gaffey, IT Tralee researcher and project coordinator, told FeedNavigator.
Protein work
The first step is to isolate two types of protein from fresh grass, for use in both cow diets but also in pig rations as well.
“We are trying to improve the protein efficiency of grass, separating out some of the soluble protein into a fraction that can be used as a pig feed; it has a relatively similar amino acid composition to dehulled soybeans.
“We also separate out some of the protein into a fiber fraction - that is primarily insoluble resistant protein, which can be used by the cow at a higher nitrogen to milk efficiency, compared to unprocessed silage. While you might expect that milk production levels would go down due to the cows receiving less protein intake, studies from Denmark and Netherlands show that is not the case. Protein conversion to milk is actually improved; you get similar milk yield and quality when compared to silage but one of the benefits is you end up with less nitrogen and phosphorus in the cattle excrement,” continued Gaffey.
Cattle and pig trials will be carried out as part of the project.
“University College Dublin will be carrying out cattle feed trials at the end of the year. Barryroe Cooperative will also be involved in some of the compounding required and they will also be supporting the pig trials.”
An additional value-added co-product in prebiotic sugars will be extracted from the deproteinised grass whey, with potential applications for the human and animal nutritional markets. Once the relevant products are extracted, large volumes of nutrient-rich whey can then be used as a fertilizer or as a co-substrate for biomethane production through anaerobic digestion.
Optimizing farmers' role in the bioeconomy
He said Biorefinery Glas is a first step towards changing the role of farmers in the bioeconomy, from suppliers of cheap biomass such as straw to the biofuel sector to producers of finished and semi-finished high value products.
“We want to make it farmer operable, to create small-scale rural enterprises.”
The partners want to facilitate several knowledge exchange activities, including training of farmers on the operation of small-scale biorefineries, so they understand how to operate the equipment, even though the technology has a high level of automation.
The biorefineries will be tested on farms in the Carbery co-operatives. “We will take the products that are produced there and carry out validation trials, and try and evaluate the business case for farmers.”
Grass grows well in Ireland, the only country in Europe with over 50% of grassland, so it makes sense to leverage that in the bioeconomy. However, there is a lot of interest in the project from other countries in the EU, particularly in how to involve farmers more in the bioeconomy, he said.
