This is the definition of monoglycerides and diglycerides according to happycow.net hidden animal ingredient list.

Here is the link: http://www.happycow.net/health-animal-ingredients.html

Here is another hidden animal ingredients site if you want it: http://www.happycow.net/health-animal-ingredients.html

There is a possibility that it could be in soap, but im not sure.
You might want to try the organic section of your grocery store, they could/usually/should have animal free things like that, you just have to make sure and it depends on location and such too.

Hope this helps! =)
References :

http://www.sms-vt.com/Monoglyceride.123.0.html?&L=1

http://www.freepatentsonline.com/5858439.html

http://ezinearticles.com/?Monoglycerides-and-Diglycerides&id=153148
References :