It is in there, the mold — those rich blue veins in creamy cheese that make you either love it or loathe it — but how does it get there? This bonus scene from Season 4, Episode 4 of Where the Food Comes From, explains how and why that happens.
The “blue” in blue cheese is mold, of course. Not ordinarily something we want to see in our food, but in the cheese world, sometimes mold is your best friend.