Extraction
The extraction of natural raw materials can be carried out using different kinds of solvents. One of the extraction processes uses pressurized carbon dioxide (CO2) under supercritical conditions. This supercritical fluid extraction process (SFE) can have many advantages compared to processes using traditional solvents, especially if the extract should be used in food-, medical- and pharmaceutical products, where high standards are needed with regard to product quality and product safety. Typical processes cover:
Decaffeination of coffee
Extraction of hops
Extraction of essential oils
Extraction of flavour
Extraction of colour pigments
High quality products by using high pressure
Using supercritical CO2 for the extraction process has a lot of advantages in comparison to processes using organic solvents, e.g.:
Easy availability
Low price
Non-toxicity
Non-explosivity
Solvent free products
Low thermal stress due to moderate temperature conditions (below 100 °C)
Easy separation of solvent and extract
Schematic depiction of the extraction process using supercritical CO2