How does the environment degrade soft gelatin capsules?

How does gelatin, specifically soft gelatin capsules, decompose in nature, i.e. in the environment, not in the body or in the kitchen? I know that such capsules are a colloid system, and that glycerol is added to gelatin.
gemshein@concentric.net

Soft gelatin capsules are prepared from gelatin, glycerin and water, and can absorb several times their own weight in water (compare the mass of a box of dry Jello with the finished product). The glycerin makes the gelatin more flexible by disrupting crosslinks between the protein chains.

If the capsules get wet enough, they dissolve. Even out of the rain, they eventually absorb enough atmospheric water to become an excellent growth medium for bacteria and fungi. These organisms will digest the gelatin using proteolytic enzymes (biological catalysts that cut long protein chains into shorter pieces).

Author: Fred Senese senese@antoine.frostburg.edu

Copyright © 1997-2005 by Fred Senese
Comments & questions to fsenese@frostburg.edu
Last Revised 07/31/07.URL: http://antoine.frostburg.edu/chem/senese/101/environmental/faq/soft-gelatin-degradation.shtml