Lecithin extraction

All lecithin is chemically extracted from bulk oils. For organic lecithin (not available in all forms and grades and very expensive due to limited supply and manufacturing capacity) organic ethanol (alcohol) is the solvent. 

All lecithin extraction processes currently employ solvents, such as hexane, to extract the oils. Hexane extraction is the most common method used in the industry to produce lecithin due to its high oil recovery and lower production cost; also, lecithin is actually defined as hexane-soluble components. These solvents are commonly recovered during the extraction step of edible oil processing through distillation and evaporation. 

To remove the hexane from lecithin, the material is treated in a vacuum distillation process because hexane is volatile and vaporizes at a relatively low temperature. The hexane evaporated during the distillation is condensed and separated from water in a decanter. The recovered hexane is then reused in the extractor. 

The European Union standard for hexane in bulk oils is a maximum residue limit (MRL) of 1 mg/kg by weight. One study published in the Journal of Experimental and Clinical Toxicology reported that the detected mean amount of hexane residue in product samples tested was 0.56 mg/kg; only 56% of the allowable amount. The EFSA Journal published a 2017 safety review concluding that there was no safety concern; even for infants and children using lecithin for special medical purposes. 

https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2017.4742

https://openaccesspub.org/ject/article/622#ridm1841927052