In the research project "Anthocyanin Extraction from Eastern Styrian Berry Family", the higher aim was to achieve so-called anthocyanins from the group of plant pigments (flavonoids) from cultivatable berry fruits in Eastern Styria.
This was done residue-free and with the appropriate purity, so that the extract can be a tradable commodity with a significant added value for agriculture:
- A first study / exploration was carried out to determine the technical feasibility of the planned production process
- (New) Use cases and technology combinations were examined by presenting and describing the possible technological components as well as their integration into the desired overall System
- Various approaches were analysed
- Finally, recommendations for further development and improvement, barriers and problems were derived.
Various extraction possibilities (also experimentally and in the laboratory of University of Technology in Graz) were considered closer. Most promising is the extraction with supercritical CO2. This process is a 2-stage process, whereby in the first extraction step non-polar substances are extracted with supercritical CO2 at a pressure of 200 bar. A major advantage of this method is the selectivity to anthocyanins. With ethanol-water mixtures of different concentrations it is possible to optimize the selective properties of the solvent. The addition of acids or sulphites can be omitted here, which on the other hand allows a very concentrated and residue-free product. The expenditure on equipment is however larger than with the alternative solution attempts.