My pa used to work in bakery during school holidays and has told me some scary tales... they once discovered at the end of the day a bread slicer had lost one of it's blades during the daily routine and so instead of opening up all the bread they just sent them out and planned to send some kind of sorry letter to whoever ended up with it.
the next day one of the delivery drivers stormed in with a piece of slicing blade and said his wife found it in their bread the night before. The boss asked which shop he had bought it from... obviously he'd picked it up off the back of his lorry and so nothing ever came of it.
he also said they had big burly men who squeezed the cream and jam into the cream cakes and quite often got it over their hands... so they just licked it off and carried on with their work! blegh!
I really really hope it wasn't what you think it was! I would be gutted as I love Asda bread!