Parmesan Cheese: When It Goes Bad And What To Do

Parmesan cheese is a hard, aged cheese with a long shelf life. Its unique characteristics and craftsmanship set it apart from other cheeses, allowing it to withstand the test of time. The meticulous aging process, which can last from 12 to 36 months, results in a cheese with very low moisture content, making it resistant to spoilage. The salt content in Parmesan also acts as a preservative, inhibiting the growth of microorganisms. Proper storage is crucial to maintaining the quality and flavour of Parmesan. When stored in optimal conditions, an unopened block can last for six to eight months, while an opened block can last for two to four months. Grated Parmesan, whether store-bought or homemade, has a slightly shorter shelf life. Vigilance for signs of spoilage, such as mould growth, off-putting odours, or changes in texture, is essential.

How to store parmesan cheese

Parmesan cheese is a hard cheese that, if stored properly, can last for up to nine months in the refrigerator. Here are some tips on how to store Parmesan cheese to maintain its quality and freshness:

Storing a Block of Parmesan Cheese:

• Keep it in an airtight container or wrap it tightly in plastic wrap or a freezer bag to prevent air exposure.
• Store it in the refrigerator, preferably in the vegetable crisper, which tends to be more humid.
• If you want to prolong its shelf life, consider freezing the cheese. Wrap it tightly to avoid freezer burn and store it in an airtight container or freezer bag.

Storing Grated or Shredded Parmesan Cheese:

• Keep grated or shredded Parmesan cheese in the refrigerator, especially if it's the fresh variety.
• Use clean utensils when handling the cheese to prevent microbial contamination.
• Store it in a sealed container or bag to maintain freshness and prevent spillage.
• Grated or shredded Parmesan cheese will typically last for about a week in the refrigerator.

Additional Tips:

• Parmesan cheese needs to breathe to prevent condensation, so avoid wrapping it too tightly.
• If you notice any mould on the surface of the cheese, remove it with a knife. Hard cheeses like Parmesan can be consumed even after removing mould spots.
• Always check the "best before" or "use-by" dates on the packaging and consume the cheese within the recommended timeframe.

Signs of spoilage

Parmesan cheese is a hard cheese that generally lasts longer than softer cheeses. However, it can still go bad, and it's important to know the signs of spoilage to ensure you don't consume spoiled cheese.

One of the most obvious signs of spoilage in Parmesan cheese is the presence of mold. Hard cheeses like Parmesan can develop mold spots, and while these spots can be cut off and the rest of the cheese consumed, it's important to inspect the cheese thoroughly. If the mold is left for too long, it can penetrate deeper into the cheese, making it unsafe to eat. Additionally, if the cheese has developed an ammonia-like smell or a strong sour odour, it's best to discard it, as this indicates spoilage.

Changes in the colour and texture of Parmesan cheese can also indicate spoilage. Spoiled Parmesan will typically darken in colour and become harder in texture. It may also feel spongy or wet to the touch, especially if it's shredded or grated. If you notice any of these changes, it's best to discard the cheese.

For shredded or grated Parmesan cheese, a change in texture can be a significant sign of spoilage. If the cheese feels spongy or wet, it should be discarded. Additionally, if the cheese has an off-putting or unusual smell, it's best to err on the side of caution and throw it out.

Proper storage is essential to prolonging the shelf life of Parmesan cheese. It should be stored in the fridge, preferably in the crisper drawer, and wrapped in wax paper, parchment paper, or aluminium foil to maintain freshness.

Storing grated parmesan

Grated parmesan cheese is a convenient way to add flavour to your dishes. But how do you store it properly?

Firstly, it's important to differentiate between the two types of grated parmesan cheese: refrigerated and unrefrigerated. The former is usually found in the cheese section of the grocery store, while the latter is sold in unrefrigerated canisters on regular aisles.

Storing Unopened Grated Parmesan Cheese

Unrefrigerated grated parmesan cheese can be stored in a cool, dry place such as a pantry. Check the “best before” date on the packaging, as it usually lasts about a year or even more.

Refrigerated grated parmesan cheese should be stored in the fridge, even if it is unopened. Check the "best before" date, as it will last for about a week past that date.

Storing Opened Grated Parmesan Cheese

Once you have opened a container of grated parmesan cheese, it should be stored in the fridge, regardless of whether it was originally sold as refrigerated or unrefrigerated.

For the best quality, use the cheese within 3-5 days of opening. However, it can be safe to consume for up to 7 days.

To prevent microbial contamination, always use clean utensils when scooping the cheese.

Freezing Grated Parmesan Cheese

If you want to extend the shelf life of grated parmesan cheese, you can freeze it. Parmesan has a low moisture content, so it is ideal for freezing and will not clump together or be susceptible to freezer burn.

To freeze, use an airtight container or the original container from the store, if it has an airtight lid. Remove the amount you want to keep in the fridge, seal the container tightly, and then place it inside a freezer bag. Label and date the container, and it should keep in the freezer for up to a year.

When you want to use the frozen cheese, give the container a tap and a shake to break up any small clumps that may have formed. Then, use a clean utensil to scoop out the desired amount and return the rest to the freezer.

Signs of Spoilage

Before using grated parmesan cheese, check for signs of spoilage. The colour should be white to beige. If it has turned yellow or darker beige, it has likely gone bad.

Another sign of spoilage is an off-putting smell. If the cheese smells funny, it is best to discard it.

If there are any signs of mould, throw away the entire package, as consuming mouldy cheese can cause stomach pain, nausea, vomiting, and even organ failure in severe cases.

Freezing parmesan

Preparing for Freezing:

• Cut the parmesan into portion-sized blocks. Consider how much cheese you want to have readily available in the fridge and cut the block into appropriate sizes.
• Decide whether you want to grate the parmesan or freeze it as a block. If you choose to grate, use the finest grater you can find as this will help the cheese withstand the freezing process better.
• Place the parmesan into airtight containers. This will prevent it from changing texture too dramatically and will stop your freezer from smelling cheesy.
• Make sure the containers are sealed tightly and are airtight. You can add another layer of protection by placing the containers in freezer bags. This will not only protect the cheese from air but also from other odours, and it will protect other foods from the odour of cheese.

Freezing Process:

• Label the freezer bag with the contents and date, then place it into the freezer.
• Parmesan wedges can be left in the freezer for over a year and will still maintain their quality.
• Shredded parmesan can be frozen for 3 to 6 months.
• If you are freezing grated parmesan, it is recommended to pre-freeze it by spreading it evenly on a cookie sheet lined with aluminium foil, parchment paper, or a silicone mat. Place it in the freezer for a couple of hours until it freezes.
• Transfer the frozen cheese into a container or freezer bag. Cut it into small pieces if it sticks together.

Defrosting and Using Frozen Parmesan:

• When defrosting parmesan, it is important to do it slowly and carefully. Plan ahead and pull the cheese out of the freezer 24 hours before you need to use it.
• Place the parmesan in the fridge to defrost slowly for several hours, depending on the size of the block.
• Do not refreeze parmesan as it will affect the texture.
• Frozen parmesan is best used in cooked dishes where it can be melted. It may not be ideal for sprinkling on salads or pasta as it will need more heat to defrost and warm up.
• Frozen grated parmesan can be added directly to dishes without defrosting.

How long does parmesan last in the freezer?

Parmesan cheese is a hard cheese made from skimmed, unpasteurized cow's milk. It has a lengthy aging process of a minimum of two years and occasionally ages for more than four years. Parmesan cheese originates from Italy, and the "true" Parmesan cheese, made only in certain parts of Italy, is called Parmigiano-Reggiano.

Freezing is a great way to extend the shelf life of Parmesan cheese. When freezing Parmesan cheese, it is best to grate the cheese beforehand and place it in an airtight container or a heavy-duty freezer bag. This way, the cheese will maintain its best quality for about 12 to 18 months in the freezer, but it can be stored safely for much longer.

When it comes to storing Parmesan cheese in the freezer, it is important to ensure that the cheese is dry and tightly wrapped. This will help prevent moisture loss and stop the cheese from drying out and moulding. It is also recommended to cut the cheese into smaller blocks, depending on the amount you need at a time, as this will make it easier to thaw and use when needed.

Once you are ready to use the frozen Parmesan cheese, you can simply remove it from the freezer and place it on the countertop for about ten minutes to defrost. If you are using shredded frozen Parmesan cheese, you can use it straight from the freezer, but be sure to break up any clumps that may have formed. It is important to note that frozen cheese may become crumbly and lose some of its flavour, so it is best suited for cooked dishes such as sauces, soups, and casseroles.

Frequently asked questions