This process is carried out on two kinds of products:

Water Soluble: This process involves the treatment of henna seeds for the extraction of water-soluble products. The seeds are first soaked in aqueous alkali (mormally potassium or sodium hydroxide) for a few minutes at a temperature of about 70 degrees. This process converts the natural bixin present in the seed coat to a simple water soluble derivative. This operation is repeated a couple of times.This alkaline extract is then filtered and acidified so as to precipitate free nor- bixin.

Oil Soluble: This process first involves soaking of henna seeds in hot water. They are then stirred and filtered which results in a paste like extraction of the seeds. A oil-soluble annatto is generated by the direct extraction of the seed coupled with a food-grade vegetable oil. The extraction process is normally carried below 70 degrees which is catalysed by mechanical abrasion. Thereafter this suspension is subjected to constant blending to lend the requisites to the standard product. Bixin crystals are finally precipitated using methylene chloride as a solvent. The resultant crystals may be crude or pure and are directly sold in the market. They are either used to prepare vegetable oil suspensions or for the conversion of water-soluble nor-bixin salt.