Does String Cheese Go Bad?  How Long Does String Cheese Last?

String cheese makes a handy snack.  It’s full of calcium, fun to peel, and small enough that it can go almost anywhere.  But how long can it last?

Quick Answer

A stick of string cheese will last around four to five hours outside of the refrigerator or insulated pack.  It will survive as long as two to three weeks past the “best by” date if unopened, and once opened lasts for about a week.  String cheese can still be good for up to eight months if it’s stored in the freezer.


While string cheese might not last very long outside of the freezer, there are ways to make it last longer.

Does String Cheese Go Bad?  How Long Does String Cheese Last?

Whether you want to eat your string cheese on the go or to save it for later, there are ways to keep it fresh as long as possible.

How Long Does String Cheese Last Outside?

String cheese should not be kept outside of a fridge without some kind of cooling source for more than two hours.  On the other hand, if you have a travel-friendly way to keep it cold for a long time like an ice pack, you can keep it fresh for as long as you need.

The cheese needs to be kept in its wrapper unopened until you’re ready to eat it.  This means that you won’t have to worry about contaminants or bacteria getting inside.

When you store a cheese stick or a pack of them inside an insulated bag, keep it away from any smelly or moist foods.  Cheese can absorb odors, although not as much as some dairy products, and it will affect the taste.  Cheese also absorbs moisture from other foods and that could make the cheese mushy and gross.

How Long Does String Cheese Last in the Fridge?

The best-known way to store string cheese is in the refrigerator.  If you don’t open the package, it can last up to three weeks past its “best by” date, although two weeks is more common.

Once you open it, the cheese lasts at least seven days.  It can be good for more, but a week is the recommended time for guaranteed quality.  Any longer and you’re running the risk of it going bad.

While string cheese may last a good long time in the fridge, that doesn’t mean you should wait to finish it.  It’s a good idea to use or eat the cheese before the “best by” date.  If you really want it to last, freeze it.

How Long Does String Cheese Last in the Freezer?

Under the right circumstances, string cheese can last up to eight months if you freeze it.  This estimate depends on what kind of cheese it’s made of; usually, string cheese is made from mozzarella cheese, which freezes very well.

Sometimes you’ll see cheddar used in string cheese, and that can freeze just as well as mozzarella.  This is because they’re about equal firmness.  Firm cheeses freeze better than softer ones.

Keep in mind that freezing your string cheese will affect its texture.  It could become harder and turn crumbly, particularly if it’s made with cheddar, losing some of its stringiness.

The estimated times that string cheese can last are, well, estimates.  Something could go wrong, like the original package being torn or the package being left outside of the fridge for too long.  It’s common sense to check for any signs of the cheese going bad before you eat it.

How To Tell if String Cheese Has Gone Bad?

String cheese can not only go bad but make you sick if you eat it.  Here are some of the signs that it’s time to throw it away.

Mold: If you see small specks of blue, gray, or green on the cheese, that’s mold.  It means that there might be a rip or hole in the packaging and you should throw it out.

It smells funny: Before you eat it, take the time to smell it.  Does it smell a bit strange?  That means the milk inside the cheese has begun to curdle.

It tastes funny: Similarly, if it doesn’t exactly taste right, then eating it isn’t a good idea and it’s time to toss it.

The color or texture is off: Does the cheese look darker than it normally would?  Does it feel mushy or slimy?  This is what happens when the proteins in the cheese start to break down.

It feels warm: If you’ve been keeping your cheese out for a trip or for a snack and it feels like it’s room temperature or warm, that means that it’s no longer fresh.  Eating it probably won’t harm you if it’s only been a couple of hours, but the quality won’t be the best anymore.

How To Store String Cheese?

Keeping string cheese cold is the key to making it last, so what are the best techniques to keeping it at the right temperature?

Outside: If you’re taking your string cheese to school or on a trip, your best bet is to keep it cold by putting it in a thermos pack.  Alternatively, putting either a cold pack or a cold drink right next to the cheese in the lunch box or bag will keep it cold enough.

Refrigerator: Keep your string cheese in the back of the fridge, away from the light, warm air, or any smelly stuff until you’re ready to eat it.  Once you’ve opened the package, you can keep it from contaminants by putting it inside a resealable container, like a plastic bag.

Freezer: Use a freezer bag to protect the cheese from freezer burn.  It’s easiest if you freeze your cheese in smaller pieces, so you won’t have to worry about cutting it or using too much.

Can You Freeze String Cheese?

Opinions tend to vary about whether or not string cheese should be frozen.  Some people say that it’s not worth the change in texture or the time it takes to thaw.  Others say that keeping the cheese good for months is worth it.

  • Generally, frozen string cheese lasts about two months before the cheese starts to change. This is because mozzarella has less water inside of it than other cheeses
  • String cheese freezes the best when wrapped in one to two layers of plastic wrap with the air squeezed out to prevent the cheese from drying out or getting freezer burn
  • Individual packs can be placed straight in the freezer. You don’t need to wrap them because they’re already wrapped, but a layer of plastic wrap or freezer bag won’t hurt
  • Don’t forget to write down the day you froze the cheese. Some freezer bags come with built-in labels for that

How to Thaw String Cheese?

Here are some tips to thaw out your string cheese:

  • Once you thaw out the string cheese, you won’t be able to put it back in the freezer anymore
  • The easiest way to thaw out string cheese is to put it in the refrigerator overnight. Or you could put it in a lunchbox with a cold pack and let it thaw out there.  Letting it thaw out at room temperature is tempting fate

Frequently Asked Questions About String Cheese’s Shelf Life

What is the shelf life of dairy-free string cheese?

The answer to this one depends on what the “cheese” is made from.  I’ve seen estimates of seven to ten days for freshness on some products, three to four months on others.  You can look at the “Best by” date on the package for a good estimate.

My cheese has mold on it.  Can I pull the moldy part off and eat the rest?

In theory, you can, but sometimes mold isn’t on the surface.  Personally, I’d discard it, but if you want to try then I recommend pulling the part that isn’t moldy open.  Check and see if there’s any mold inside before you eat it.

Wrap Up

Here’s one more good thing about string cheese: it never loses its vitamins or minerals during storage, even in the freezer.  So, feel free to keep a pack handy for any emergency food cravings!

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