What Causes Foul Smelling Bowel Movement In An Infant?

My 20 month old little boy frequently has poop that smells like bad breath. His poop smells so bad it permeates the room, lol, and we have to febreeze and throw the diaper outside in a bag in the trash. Needless to say It is extremely smelly, and I can t figure out why it would smell so bad. It smells worse than a grown man s #2. It smells just like really stinky old lady breath, sort of like super nasty halitosis. We don t eat processed foods, or packaged foods much. Mostly only homemade foods. He does drink V8 two or three times a day, and also has a cup of whole milk twice a day. He does prefer meats, breads and cheeses to veges or fruits. (?????)