Natural raw materials are often altered to prepare them for consumption. A standard process in the food industry is extraction with the aim of increasing the concentration of components in the starting material. Extraction is the isolation of pure substances from a material mix of substances using a suitable solvent. As a rule, organic solvents with a low boiling point such as methanol, ethanol, dichloromethane etc. are used. As some of these materials are toxic, their use today is avoided where possible.