It's a shame to waste uneaten food, but when mould appears it's often a sign that something is ready to discard. The answer isn't quite as clear when it comes to cheese, however, as mould is only a problem in certain situations. Here's how you can tell.
Photo by Stephanie Watson.
Registered dietitian Katherine Zeratsky, over at the Mayo Clinic, explains which cheeses succumb to the dangerous effects of mould and which ones remain edible:
The answer depends on the type of cheese. Soft cheeses, such as cottage cheese and cream cheese, that grow mould should be discarded. With these cheeses, the mould can send root threads throughout the cheese. In addition, harmful bacteria, such as listeria, brucella, salmonella and E. coli, can grow along with the mould. The same goes for any kind of cheese that's shredded, crumbled or sliced.
Mould generally can't penetrate far into hard and semisoft cheeses, such as Cheddar, Colby and Swiss. So you can cut away the moldy part and eat the rest of the cheese. Cut off at least one inch around and below the moldy spot. Be sure to keep the knife out of the mould itself so that it doesn't contaminate other parts of the cheese.
Those are the basic rules, but be sure to check out the full post over at the Mayo Clinic for a handy chart that outlines specific cheeses and their susceptibility to mould.
If a piece of cheese has mould on it, should I throw the cheese away? [The Mayo Clinic via the Consumerist]