Force open a file with the UTF-8 encoding
This is the kind of thing that BBEdit was made for. BBEdit will open any file and generally do an excellent job of displaying any embedded text. There is even a menu in the bottom control area for every file that allows you to force a particular text encoding. When I first bought BBEdit it was about $130. At its current price of $50 its a steal. I have no affiliation with Barebones Software, except as a satisfied customer.

http://barebones.com/products/bbedit