How is Glucosamine for Dogs Made?

Glucosamine for Dogs is usually extracted from the shells of shellfish (Lobster, crab, crawfish, shrimp, etc.).  

The primary technique for making the best selling form of glucosamine is as follows:

• Grinding:  The shellfish shells are ground into a fine particulate.
• Reactor:  The ground shells  are then mixed with hydrochloric acid (HCl) to cause Acid Hydrolysis of the shellfish chitin (chitin is the shell material containing glucosamine)
• Filter:  Glucosamine HCl will precipitate out of the solution during the reaction step and the precipitate is then filtered.
• Decoloring:  The filtered Glucosamine HCL crystals are cleaned by dissolving the crystals in a solution of water and activated charcoal to remove any color.
• Crystallization:  The dissolved Glucosamine HCl is extracted from the water and formed into crystals
• Centrifugation:  The Glucosamine HCl crystals are separated and purified through a centrifuge.
• Drying:  The Glucosamine HCl is dried, leaving pure Glucosamine HCl, which looks like a white powder.

This is just one process for manufacturing one of the Glucosamine forms.  The three primary forms of glucosamine are glucosamine sulfate, glucosamine hydrochloride and n-acetyl glucosamine.  Due to the differences in chemistry, the production process of each will be slightly different.

Proposal for making a “Substantial Equivalence” notification for Non-Shellfish Glucosamine Hydrochloride under Regulation (EC) No 258/97 for the European Parliament and of the Council of 27 January 1997 concerning novel foods and novel food ingredients., Cargill Acidulants, February 5, 2004.

Preparation Of Glucosamine Hydrochloride - Patent 6486307, DocStoc (accessed 4/2012)