Okay...since a lot of cheese experts are going to read this, perhaps one of you can tell me: How do you know when Roquefort cheese goes bad?
Ummmm ... when it gets moldy?
There's an Australian cheddar they sell around here that claims 7 years, but it's not consistent from wheel to wheel, so we don't get it that often. Since everyone here has a lactose problem we love the aged cheddars ~ minimum 9 months!
Goat's milk and mare's milk cheddars are also locally available and I pick up half pound blocks several times a year.
A former housemate had blue cheese go bad. (Answer: That’s when it gets hairy.) On throwing it away, another housemate declared: “Strike Three; you go bad three times, you’re out.)
(If you don’t get it, Milk goes bad and becomes cheese. Cheese goes bad and becomes blue cheese...)
It starts smelling good?
When there's no cheese left to hold the mold together. Until then, at least some of it is salvagable - but it does get really tangy when it has had time to get that far along...