? Cheese Spoiled
According to a study quoted at this site, http://www.safespectrum.com/applicati...
"Approximately two to five percent of the top or front pieces of Cheddar or Colby cheese in supermarket retail display cases show definite evidence of pink discoloration and potential oxidized flavor.
"Wendorff identified three major factors that cause discoloration. The primary culprit is the fluorescent lighting in retail cases that catalyzes the pinking effect."
So I would say go ahead and bake with it.