I found a couple of websites with info that maybe helpful. Here' are the links:
http://www.housekeepingchannel.com/a_173-Fridge_Smells_that_Wont_Go_Away
http://www.fixya.com/manuals/w153202-get_rid_bad_smells_in_refrigerator
http://www.housekeepingchannel.com/a_173-Fridge_Smells_that_Wont_Go_Away
http://www.fixya.com/manuals/w153202-get_rid_bad_smells_in_refrigerator