Organofinery: a biorefinery for the production of organic protein-rich feed for monogastric animals

Nowadays, the organic farming sector is rapidly increasing in order to meet the increasing demand for organic products. However, the scarce availability of organic feed for monogastric animals together with the lack of organic fertilizers are challenging the development of this sector. In this context, a Danish project called Organofinery is developing a green biorefinery platform for the production of organic protein-rich feed for monogastric animals, of biogas and of organic fertilizer.
In the Organofinery concept, the freshly harvested green biomass is separated by a screw press into a green juice and a press cake. Soluble sugars contained in the green juice are fermented by specific lactic acid bacteria, leading to a drop of the pH and triggering protein precipitation. The resulting protein concentrate is purely organic and rich in non-denatured proteins, making it a high-value protein feed product for organic farming. The residual press cake and brown juice are tested to be used as feedstock for biogas production and subsequent use as organic fertilizer.
Protein extraction yields in the protein product were in the range of 15 to 23% for various green crops. On average, the protein concentrates contained 18% dry matter and 35-40% true protein (dry weight). Therefore, up to 10 kg dry protein product can be produced from 1 ton of fresh green biomass by the Organofinery process. Moreover, the organic protein concentrates showed high content of sulfur amino acids, which are regarded as important amino acids in diets for monogastric animals.
Protein processing will be tested in pilot scale in June 2016. Around 200 tons of freshly harvested clover grass will be processed in the Organofinery concept to produce 2 tons of dry protein product. Afterwards, a full feeding experiment with egg-laying hens will be performed to assess the safety and quality of the protein product as organic protein feed for monogastric animals.
The conducted experiments have shown the potential of the Organofinery concept and the imminent pilot scale experiment should proof its applicability to provide protein-rich feed for the farming sector.