When you’re looking on the back of packets to see if they contain milk or lactose, you may notice that lots of foods actually say “May contain traces of milk”. Does this mean milk might accidentally be used? Or that they aren’t sure? So what does it actually mean when they say “may contain traces of milk?”
Well typically it means that is is made on the same equipment that handles milk (or whichever ingredient they mention) This really shouldn’t be an issue for most people, as the machines are cleaned between new ingredients going in, but for legal and “just in case” reasons, they list that it may in some rare cases contain a trace of milk. This shouldn’t effect most people, but if you’re severely allergic to an ingredient its good to know.
/Edit – Costa have replied about one of their latest products and said “Just heard back and the product is free from dairy; the warning is standard due to cross contamination in-store”
So you’ll be good to go in most cases, just don’t worry too much.