Why You Can Trust CNET Here's How Long Different Cheese Types Last, and How to Know When It's Time to Toss Them
Don't trash that fancy cheese over a bit of mold. Here's how long various types of cheese last and how to know when it's really time to say au revoir.
The short answer to when you should throw out that moldy cheese is: Maybe never, depending on the type of cheese and degree of mold -- but of course it's not quite as simple as that. Here's something that most people don't like to hear when it comes to one of our favorite food products, but I promise it will save you from the heartbreak of thinking you have to discard perfectly good cheese: "Even though we've been taught to fear mold, all of cheese is mold," says Anne-Marie Pietersma, a certified cheese professional, educator and writer.
All cheese is mold. Let that sink in a moment. While certain cheeses -- looking at you, blue -- sport their mold more proudly than others, cheesemaking is a process that encourages the growth of particular types of microorganisms, including mold. The bright white rinds of brie and camembert are mold. The mottled exteriors of aged English cheddars and alpine-style cheeses include mold. The sticky orange outside of delightfully dank washed-rind cheeses is a form of mold.
Read more: Here's How You Should Store Your Cheese
But this is good news when you think about it. "Just the fact that cheese is already a preserved product, we don't have to worry about a lot of the things that we do with other foods," says Pietersma. "The biggest mistake I see people make is to think that cheese is something porous like bread and that you have to throw it away when it starts growing mold." In addition to its generally low moisture content, cheese is also high in other elements that help prevent spoilage, such as salt and acid. While black mold might be evidence of something more sinister lurking in your fridge, for the most part, mold isn't a great concern when it comes to cheese.
Of course, there are exceptions and variations to this rule, so here we delineate different types of cheese, in order of their degree of delicateness, and what to fear and not fear if they start to grow mold. And for more smarts to help feed your addiction, here's how to properly store cheese and how to find the best cheese for cheap.
Fresh cheese: Probably discard
Fresh cheeses like chèvre, feta, mozzarella and ricotta have a far shorter shelf life than their aged counterparts.
Fresh cheeses are those that are rindless, that spend little or no time aging between the time when the curds are formed and the time they are ready for consumption. Think chèvre, feta, mozzarella, ricotta, etc. Because these are high-moisture cheeses that are designed to be consumed, well, fresh, they are a little more susceptible to actual spoilage.
"Moisture is the enemy of storage," says Pietersma, and one of the elements that causes spoilage mold to grow. So with fresh cheeses, whose moisture content is a lot higher since they haven't had a period of aging to dry out, "that moisture kind of acts like a groundwater system," she says, "so you can't really tell where the mold might go. So if you do see mold on a fresh cheese, you should probably throw it out."
Read more: Fake Parmesan Cheese Is a Bigger Problem Than You'd Think
Certain fresh cheeses (such as feta or mozzarella) that are sold in vacuum-sealed packages might have an expiration date of a few weeks to a few months, but that only applies so long as the package has remained sealed. On the other hand, if it's been hanging out in the back of your cheese drawer, unopened, beyond its expiration date, so long as it isn't showing signs of mold, it's probably still good to eat. Cheese will typically become unpalatable to you before it becomes unsafe.
Soft cheese: Cut off and keep going
Soft cheeses are those that are young, but not fresh. They still have some moisture but have usually aged out in a cheese cave or aging environment for a week or more. Think brie and other bloomy rind cheeses, as well as some washed rind cheeses. If it pudges when squeezed, or is gooey when cut into, these are the soft cheeses we're talking about.
Et voila!
For these types of cheese, "you can just cut off the mold and keep going," says Pietersma, but notes there's an element of personal preference here. "Cheese won't age in your fridge, but it will become more of what it is," she says, "so whenever it gets too strong for you, or changes in texture to a point where you don't like it anymore, then throw it away. But as far as it being unsafe. It's really difficult to get to that point."
Blue cheese: Mind the smell
With blue cheese, your nose can tell you everything you need to know about whether or not it's gone bad.
What to do with blue cheese then, since it already wears its mold as a badge of identity? "People always ask about knowing what's the good mold and what's the bad mold in it," says Pietersma, "since there's already so much visible blue and green veining." While anything that's obviously just on the surface or the rind of the cheese can simply be cut off, blue cheese can also require other senses to determine whether it's good to still consume.
"That is where I go by smell," says Pietersma. Blue cheese, while not the stinkiest of cheeses, can have earthy or funky smells, but for signs of spoilage, you're looking for something specific. "If it's ammoniated in any way, it's probably done," she says.
Some blue cheese can have a subtle ammonia smell that isn't evidence of being past its prime, but, "that can be accelerated by improper storage," says Pietersma. "If you put your blue cheese in plastic wrap, or a Ziploc bag, cutting off exposure to oxygen, and not letting the cheese breathe, that's definitely what speeds up that process."
Try this instead: Formaticum Cheese Storage Bags
Firm or aged cheese: Never let me go
Those white spots on your hard cheese are just amino acid clusters and they're perfectly safe to eat.
The harder the cheese, the longer it aged, and the least susceptible it is to any kind of meaningful spoilage since there's little to no moisture left to encourage mold growth. You may notice at your local cheese retailer that cheeses that undergo more than a year of aging such as Parmigiano Reggiano, and certain goudas, hardly even need refrigeration. While letting them sit out for hours in an open-air environment, such as if you're serving them at a party, may cause them to dry out or change in texture in such a way that becomes less palatable, according to Pietersma: "Those boys are hardy," she says. "Nothing can really take them down."
What about those white clusters on your Parmigiano Reggiano? Those are simply amino acid clusters. They're natural, shouldn't affect the cheese flavor profile much and are perfectly safe to eat.