Plant extraction is a process that aims to extract certain components present in plants. It is a solid/liquid separation operation: a solid object (the plant) is placed in contact with a fluid (the solvent). The plant components of interest are then solubilised and contained within the solvent. The solution thus obtained is the desired extract. The solvent will eventually be eliminated to isolate the plant extract. If it is for the food industry, it is not necessary to separate it from the extract. If not, a second separation operation makes it possible to obtain a dry extract. Nowadays, the term “extract” is frequently used incorrectly. In fact, only solid/liquid extraction is capable of producing them, but sometimes simple crushed plant powders are marketed as “extracts”.