Processed cheese? That stuff is just emulsified oil. Regular cheese may or may not have bacteria in it. Regardless, if you clean the buckets well (i.e. oxyclean and very hot water followed by starsan) you'll be fine.
"I can't believe how many people think Air Lock is pronounced Hydrometer." -BigKahuna
"If you gave me a beer with placenta in it without telling me I would kick you in the nuts." -ODaniel
"We be in a big hurry for dope beer with much alcamahol and flavor, quality, balance, and aroma don't matter. We just wantz to be druck, u know?" -Yooper