Parmesan Cheese: How Long Does It Stay Fresh?

Parmesan cheese is a hard cheese with a long shelf life, but how long it lasts depends on how it is stored and whether it has been opened. If stored in the refrigerator, an unopened package of Parmesan can last several months beyond its expiration date. Once opened, a block of Parmesan will last in the fridge for up to two months, while grated Parmesan will last for about a week.

Opened vs. unopened

The shelf life of Parmesan cheese depends on several factors, including whether it is opened or unopened, its form (grated, chunk, or block), and the storage conditions.

Unopened Parmesan Cheese

An unopened package of Parmesan cheese can last for several months beyond its expiration date, provided it has been stored properly. A whole, unopened block of Parmesan cheese can be stored in the refrigerator for seven to nine months and will remain safe beyond that time. Vacuum-packed Parmigiano Reggiano, a specific type of Parmesan cheese, can be stored in the refrigerator for several months.

Opened Parmesan Cheese

Once a package of Parmesan cheese is opened, its shelf life depends on how well it is sealed and stored. A block of opened Parmesan cheese will typically last in the refrigerator for one to two months. To maximize the shelf life of an opened chunk or block of Parmesan cheese, it is recommended to wrap the original packaging tightly in plastic wrap or aluminum foil. For even better results, wrap the cheese first in wax or parchment paper and then cover it with plastic wrap before refrigerating.

Grated Parmesan cheese sold unrefrigerated and then opened will generally stay at best quality for about 10 to 12 months in the refrigerator. To extend the shelf life, it is recommended to store it in an airtight container or freezer bag and place it in the freezer, where it will maintain its best quality for about 18 months.

Grated vs. block

Parmesan cheese has a long shelf life, especially when stored properly. When stored in the refrigerator, it can last for several weeks to months. If unopened and in its original packaging, it can last for several months beyond the expiration date. Once opened, its shelf life depends on how well it is sealed and stored.

Grated Parmesan Cheese

Grated parmesan cheese is more prone to clumping and spoilage than a block of parmesan. The increased surface area of grated cheese means it is more likely to absorb moisture and spoil. Therefore, it is best to use grated parmesan within two weeks of storing it. To extend its shelf life, it should be stored in an airtight container or vacuum-sealed bag in the refrigerator, at temperatures below 40°F (4°C).

Opened, commercially packaged, grated parmesan cheese that was sold unrefrigerated will generally stay at best quality for about 10 to 12 months in the refrigerator. To further extend its shelf life, it can be frozen and will maintain its best quality for about 18 months. However, frozen parmesan cheese may lose some of its texture and flavour.

Block Parmesan Cheese

A block of parmesan cheese will last up to 9 months if left unopened and stored in the fridge. When opened, it will last 4-8 weeks. To store a block of parmesan cheese, it is recommended to wrap it in parchment paper and then aluminium foil, or to place it in a Ziploc bag with the excess air removed.

Signs of Spoilage

Spoiled parmesan will change colour from light to dark, develop a harder texture, and may have green mould on the surface. It will also have a mouldy or sour smell. If mould is present on the surface of hard cheeses like parmesan, it is generally safe to cut off the affected portion, and the rest of the cheese should still be usable.

Freezing

Preparing Parmesan Cheese for Freezing

Before freezing, it is important to properly prepare your Parmesan cheese to ensure the best quality and prevent spoilage. Here are some key steps:

• Grate the Cheese: Grating the cheese before freezing helps to preserve its texture and makes it easier to use in cooked dishes after thawing.
• Use Airtight Containers or Heavy-Duty Freezer Bags: Place the grated Parmesan cheese in airtight containers or heavy-duty freezer bags. This helps to prevent freezer burn and maintains the quality of the cheese.
• Wrapping: If you are freezing a block of Parmesan cheese, you can wrap it in parchment paper, cheesecloth, cheese paper, or wax paper before placing it in the freezer. This allows the cheese to breathe and prevents condensation, which can lead to spoilage.

Storage Times for Frozen Parmesan Cheese

Once your Parmesan cheese is properly packaged and stored in the freezer, it can last for quite a long time:

• Grated Parmesan Cheese: When stored in airtight containers or freezer bags, grated Parmesan cheese can maintain its best quality in the freezer for about 18 months. However, it will remain safe to consume even beyond this time frame.
• Block of Parmesan Cheese: A block of Parmesan cheese can be stored in the freezer for over a year. The key is to ensure that it is properly wrapped to prevent moisture accumulation and spoilage.

Thawing and Using Frozen Parmesan Cheese

When it comes to using your frozen Parmesan cheese, here are some guidelines to follow:

• Thawing: If you have frozen a block of Parmesan cheese, you can defrost it by placing it on a countertop at room temperature for about ten minutes before using it. For grated frozen cheese, you can simply give it a shake to break up any clumps before adding it to your dishes.
• Suitability: Frozen and thawed Parmesan cheese is best suited for cooked dishes such as sauces, soups, and casseroles. It may lose some of its texture and flavour, but it will still add taste and creaminess to your recipes.
• Storage After Thawing: If you have thawed your Parmesan cheese in the refrigerator, it can be kept for an additional 3 to 4 days before using it. However, if you thawed the cheese in the microwave or cold water, it should be used immediately.

Signs of Spoilage

Even when frozen, it is important to check for any signs of spoilage before consuming Parmesan cheese. If the cheese develops an off odour, flavour, or appearance, it is best to discard it. Additionally, if mould appears, discard the cheese to prevent potential foodborne illnesses.

Signs of spoilage

Parmesan cheese is a culinary treasure, renowned for its rich, nutty flavor. However, it can be tricky to know when it's past its prime. Here are some detailed signs of spoilage to look out for:

• Mold: The presence of any mold, regardless of color or size, is an unmistakable sign of spoilage. If you spot any mold, discard the cheese immediately. If only a small portion of the cheese is affected, you can cut it off and consume the rest. However, if the entire cheese is covered in mold, it's best to throw it away.
• Discoloration: Parmesan cheese typically has a golden hue. Any change in color, such as a darker or paler shade, or the presence of yellow or brown spots, can indicate spoilage. Small discolored areas can be cut off, but if the entire cheese is streaked with spots, it's best to discard it.
• Texture: Parmesan cheese should have a firm and slightly grainy texture. If it becomes soft, crumbly, or noticeably drier than usual, it may be a sign of spoilage.
• Smell: A strong, sour, or rancid odor is a clear indication that your Parmesan cheese has gone bad. Parmesan is known for its nutty fragrance, so any deviation from this scent could be a red flag.
• Taste: If you notice a bitter or otherwise unpleasant taste, it's a telltale sign that your Parmesan cheese has spoiled. Trust your taste buds—if it doesn't taste right, it's best to throw it out.
• Expiration Date: Always check the expiration date on the packaging. While Parmesan cheese can last beyond this date, especially if unopened, it's important to be mindful of this guideline.

It's important to note that proper storage plays a crucial role in preserving the quality and extending the shelf life of Parmesan cheese. Store it in an airtight container in the refrigerator, ensuring it's well-sealed to prevent moisture loss and the absorption of odors. With proper storage, you can enjoy your Parmesan cheese for several weeks to months.

Storage conditions

Parmesan cheese has a long shelf life, but it does require proper storage.

If you have an unopened package of Parmesan, it can last for several months beyond the expiration date, as long as it has been stored properly. Once the package is opened, its shelf life depends on how well it is sealed and stored.

To extend the shelf life of opened Parmesan cheese, it should be kept in the refrigerator at temperatures below 40°F (4°C). It is important to ensure that the cheese is well-sealed to prevent it from drying out or absorbing odours from the refrigerator.

For grated or shredded Parmesan, consider using a vacuum-sealed bag or a container with a tight lid. This will help to maintain its quality and flavour.

If you are storing a chunk or block of Parmesan cheese, it is recommended to wrap the original packaging tightly in plastic wrap or aluminium foil. For even better results, wrap the cheese first in wax or parchment paper and then cover it with plastic wrap before refrigerating. This will help to keep the cheese fresh and prevent spoilage.

Additionally, it is important to store Parmesan cheese away from other foods, as the fatty part of the cheese can absorb other smells from the refrigerator. You can also store it in glass or plastic containers to maintain its organoleptic features.

Another option for storing Parmesan cheese is to freeze it. Grated Parmesan cheese can be placed in covered airtight containers or heavy-duty freezer bags. A block of Parmesan cheese can be frozen in an airtight container or freezer bag as well. Frozen Parmesan cheese may lose some of its texture and flavour, so it is best suited for cooked dishes such as sauces, soups, and casseroles.

When storing Parmesan cheese, always follow any specific storage instructions provided on the packaging.

Frequently asked questions