Biorefinery Glas: Production of grass whey and its suitability for fertiliser and bioenergy applications.

A fact sheet on the potential use of grass whey as a biofertiliser and used to produce bioenergy. Biorefinery processed fresh grass can be processed to produce a presscake fibre feed for ruminants, and a protein concentrate which can serve as monograstric feed. A high value sugar stream, rich in fructo-oligosaccharides, a prebiotic, can be extracted from the remaining liquid, leaving a residual stream called “whey” which contains many nutrients, minerals and sugars. In the sections below we will detail the potential of using this whey as a bio-fertilizer or for the production of bioenergy through anaerobic digestion. Overall, four product streams were evaluated. Presscake fibre was produced as cattle feed. Green protein concentrate was produced for monogastrics. A prebiotic, fructo-oligosaccharides was extracted. The residual grass whey can remain on the farm as fertilizer. Grass whey process residues can also be used for the production of biogas through anaerobic digestion.