Using expired grated Parmesan cheese is generally not recommended. However, grated Parmesan cheese may still be safe to consume after the expiration date, depending on how it was stored and the quality of the cheese.
Quick Answer
Grated Parmesan cheese can usually be used for up to 4-6 weeks past the printed expiration date if it has been continuously refrigerated and the package is not open. However, expired grated Parmesan should not be used if mold is present or if the cheese smells bad or tastes bitter.
How can you tell if grated Parmesan cheese is still good?
Here are some signs that grated Parmesan cheese may still be safe to use after the expiration date:
- It has been stored properly in the refrigerator continuously and the package is unopened. Refrigeration slows bacteria growth and keeps cheese fresher longer.
- It still has a vibrant white color with a powdery texture. Discoloration, clumping, or hardening indicates spoilage.
- It smells normal, without any sour, ammonia, or moldy odors. Rancid smells mean the cheese should be discarded.
- It tastes like aged Parmesan, without bitterness or other “off” flavors. Bitterness or sourness is a sign of spoilage.
On the other hand, grated Parmesan should definitely be discarded if:
- It has visible mold growth anywhere in the package.
- It smells “off” or rotten in any way.
- It tastes bitter, sour, or unpleasant.
How long does grated Parmesan cheese last after opening?
An opened package of grated Parmesan will usually last:
- Refrigerator: 2-3 weeks past printed expiration date
- Freezer: 2-3 months past printed expiration date
To maximize freshness after opening, re-wrap the Parmesan tightly in plastic wrap or store in an airtight container. Minimize air exposure and keep refrigerated at all times. Discard if mold develops or if you notice any sour or rancid smells.
What happens if you eat expired grated Parmesan?
Typically, properly stored and handled grated Parmesan is very low risk even a few weeks past its expiration date. At worst, expired Parmesan may not taste as robust or flavorful.
Rarely, consuming spoiled Parmesan could potentially cause foodborne illness. Contaminated cheese that contains high levels of bacteria or mold can potentially lead to symptoms like:
- Nausea or vomiting
- Diarrhea
- Abdominal cramps
- Headache
- Fever
People with compromised immune systems, pregnant women, young children, and the elderly are most at risk for illness from consuming contaminated foods.
How to store grated Parmesan cheese properly
To maximize freshness and shelf life of grated Parmesan cheese:
- Buy only what you will use quickly – grated cheese has a shorter shelf life than block Parmesan. Opt for smaller containers.
- Keep refrigerated at 40°F or below – the cool temperature prevents bacteria growth and slows staling.
- Seal the package tightly – don’t let air inside as exposure to oxygen can accelerate spoilage.
- Use clean utensils – don’t introduce new bacteria into the container that could multiply.
- Use within 2-4 weeks of opening – consumed grated Parmesan within this timeframe for best quality and safety.
Can you freeze grated Parmesan cheese?
Yes, it is possible to freeze grated Parmesan cheese for longer term storage. To freeze grated Parmesan:
- Make sure the cheese is not already expired or close to the printed expiration date.
- Portion the grated Parmesan into airtight freezer bags or containers, removing as much air as possible.
- Label the containers with the date and freeze at 0°F or below.
- Use within 2-3 months for best flavor and texture.
- Thaw in the refrigerator before use.
Freezing prevents further moisture loss and can stop bacteria growth, extending the shelf life. However, freezing may intensify the flavors as Parmesan continues to age at freezer temperatures.
Can you freeze Parmesan cheese block?
Freezing blocks or wedges of Parmesan cheese is also an option. To freeze Parmesan cheese blocks:
- Cut the cheese into smaller portions if needed.
- Wrap tightly in plastic wrap, forcing out as much air as possible.
- Place in freezer bags or airtight containers.
- Freeze for up to 6 months at 0°F or below.
- Thaw refrigerated overnight before use.
Let the cheese come to room temperature before grating for easier shredding. Properly frozen cheese blocks retain their texture and flavor well when thawed.
What happens if you freeze Parmesan cheese?
Freezing has these effects on Parmesan cheese:
- Slows down aging and bacteria growth
- Minimizes moisture loss
- Can intensify flavor as cheese continues to age at freezing temperatures
- May increase crumbliness when grated after thawing
- Can preserve texture well if thawed overnight in the refrigerator
Overall, freezing is an excellent way to extend the shelf life of Parmesan cheese while preserving the taste and texture fairly well. Thaw overnight before grating or eating for best quality.
Can you use expired Kraft grated Parmesan cheese?
Kraft grated Parmesan cheese typically has a shelf life of 10 to 12 months if unopened. Once opened, it will stay fresh in the refrigerator for 3 to 4 weeks after the printed “best by” date.
Unopened packages can sometimes be safely used for up to 4 to 6 weeks past the expiration date, provided they have been continuously refrigerated at 40°F or below. However, quality and flavor will start to decline over time.
If the cheese has developed an off smell, flavor, or appearance, it should be discarded. Never use grated Parmesan from Kraft or any brand if there is mold present.
How to tell if Kraft grated Parmesan cheese is bad?
Signs that Kraft grated Parmesan has spoiled and should be thrown out include:
- Mold growing anywhere in the package
- Darkening or dulling of the white color
- Hardening or clumping of the texture
- Sour or bitter flavor
- Ammonia, rotten, or “off” smell
If the cheese smells pungent but still edible, it may still be safe but will likely not taste very good. Rancid or ammonia odors indicate full spoilage.
Does Parmesan cheese expire?
Yes, Parmesan cheese does expire, though unopened Parmesan wedges often keep well for over a year past the “best by” date printed on the package.
Here are some general Parmesan cheese expiration timelines:
- Unopened block: 1 year from production date
- Opened block: 3-6 months in refrigerator
- Grated: 10-12 months before opening
- Opened, grated: 3-4 weeks in refrigerator
However, these timeframes can vary based on storage conditions. Properly stored Parmesan can keep for months or even years without necessarily “going bad” from a food safety standpoint.
How long does Parmesan cheese last after expiry?
Here are some guidelines for how long Parmesan lasts past its expiry date if properly stored:
- Unopened block: Up to 1 year past printed expiry
- Opened block: 2-4 months past expiry date
- Unopened grated: Up to 6 months past expiry if refrigerated
- Opened grated: Up to 4 weeks past expiry if refrigerated
The shelf life depends on storage conditions. Refrigeration at 40°F or below extends the lifespan of Parmesan cheese significantly. Discard if mold develops or if you notice any rancid odors or flavor.
Can Parmesan cheese be frozen?
Yes, it is safe to freeze Parmesan cheese to extend the shelf life beyond the expiry date. Here are some tips:
- Cut Parmesan blocks into smaller portions before freezing if needed.
- Wrap tightly in plastic wrap, squeezing out air.
- Place in airtight bags or containers in the freezer at 0°F or below.
- Label with date and use within 4-6 months for best quality.
- Thaw overnight in the fridge before using.
Freezing stops aging and bacteria growth. Thawed Parmesan may have slightly different texture and flavor but is still high quality. Grated Parmesan can also be frozen for 2-3 months.
Can you eat Parmesan cheese after expiry date?
Parmesan cheese is typically safe to eat after the expiry date, provided it has been properly stored and there are no signs of spoilage like mold, sour odor, or off tastes.
Hard cheeses like Parmesan have a very low moisture content, which makes it difficult for harmful bacteria to grow. Refrigeration also slows any bacteria growth.
For best quality flavor and texture, Parmesan cheese is ideally consumed before the expiry date. But unopened blocks can often last for months or even over 1 year past the printed date if refrigerated. Smaller pieces may get dried out but are still safe to eat.
Use your judgment to check for mold and off odors or flavors. But overall, Parmesan has a very long shelf life compared to other cheeses due to its hard texture and low moisture.
Does Parmesan cheese go bad?
Parmesan cheese can go bad eventually, but it tends to have a very long shelf life compared to other cheeses. Some signs that Parmesan has spoiled and should be discarded include:
- Mold growth on the cheese
- Sharp, sour, or bitter flavor
- Unpleasant or “off” smell
- Soft, crumbly, or dried out texture
- Discoloration or darkening
Thanks to its hard texture and low moisture content, properly stored Parmesan lasts for months or even over a year past its expiry date before going bad. Keep refrigerated at all times to extend the lifespan. But discard if it develops mold or unpleasant tastes or textures.
What happens if you eat expired Parmesan cheese?
Eating small amounts of expired Parmesan is unlikely to cause food poisoning or illness, though the flavor and texture quality may decline. Hard cheeses like Parmesan are very low risk because bacteria have a hard time growing in the low moisture environment.
However, there is a small risk of foodborne illness if the cheese has become contaminated. Consuming moldy cheese or cheese with high levels of bacteria could potentially cause symptoms like nausea, vomiting, diarrhea, fever, headaches, etc.
Pregnant women, young children, the elderly and those with weakened immune systems have a higher risk for illness from spoiled foods. But for most healthy adults, eating expired Parmesan should not cause issues as long as it was properly stored. Discard if mold develops.
Conclusion
Parmesan cheese typically keeps well past the printed expiry date if it has been continuously refrigerated. Unopened, it can often last for over a year. But use your judgment checking for mold growth, sour odors, bitter taste, or other signs of spoilage before consuming expired Parmesan.
While it may not taste as robust or flavorful, properly handled Parmesan is unlikely to pose health risks even several weeks or months past its expiry. Hard cheeses like Parmesan have very low moisture so harmful bacteria are unable to grow easily. Refrigeration also slows any bacteria growth.
For best quality and flavor, use Parmesan cheese within the expiry timeframe. But know that an expired product you have on hand doesn’t necessarily need to be thrown out if it still looks and smells normal. With proper storage like consistent refrigeration, Parmesan can be safe long after its expiry date in most cases.