How do you keep Parmigiano Reggiano from molding?

Parmigiano Reggiano, often referred to as Parmesan cheese, is a hard Italian cheese made from cow’s milk. It has a rich, complex flavor and a granular texture. Parmigiano Reggiano is also frequently used as a cooking ingredient to add a savory, nutty flavor to dishes. However, like many cheeses, Parmigiano Reggiano is prone to mold growth if not properly stored.

Why Does Parmigiano Reggiano Mold?

Cheese naturally contains moisture, proteins, and sugars – all things that mold thrives on. Hard cheeses like Parmigiano Reggiano have less moisture than soft cheeses, but they still contain enough to allow mold growth under the right conditions. The mold spores are everywhere in the air and easily find their way onto the cheese. Warm temperatures and high humidity provide ideal conditions for the spores to germinate and grow.

The mold growth usually starts on the outside, where the spores first landed. Molds can send root threads deep into the cheese interior. If uncontrolled, mold can lead to spoilage and an unfavorable flavor in part or all of the cheese.

Tips to Prevent Parmigiano Reggiano from Molding

Proper storage is key to preventing mold growth and keeping Parmigiano Reggiano fresh for as long as possible. Here are some tips:

Keep It Cool

Cold temperatures slow down mold growth. Store Parmigiano Reggiano in the refrigerator, wrapped in parchment paper or cheese paper. The ideal temperature range is 35°F to 40°F. If you have a cheese compartment with controls to maintain higher humidity, even better. Just avoid freezing the cheese since freezing can cause texture changes.

Use a Cheese Box or Bag

A dedicated cheese storage box, or a resealable plastic bag, can help control humidity levels. Choose a container with enough room for air circulation. Avoid airtight plastic containers that can trap in moisture and create the perfect breeding ground for mold.

Wrap It Well

Wrap the cheese first in cheese paper, parchment paper, or wax paper before putting it in a storage container. Make sure the paper fits the cheese snugly and seals it off from air exposure. Replace the wrap with a fresh sheet every couple of days.

Keep It Dry

Use a dry cloth or paper towel to pat off any moisture on the cheese surface before wrapping it for storage. Throw out any cheesecloth packaging it originally came in, as that can harbor mold spores. Discard any cheese that shows signs of moisture or sliminess.

Check for Mold

Inspect your Parmigiano Reggiano regularly for signs of fuzzy mold starting to form. Look closely at the rind and cut into the cheese if needed. Discard any portions with mold. Clean the knife after trimming to avoid spreading spores.

Don’t Use Damp Wrappers

Never use damp or wet paper to wrap cheese. Moisture supports mold growth. Use dry sheets of fresh wrap only.

Keep Cut Pieces Separate

Once you cut into the cheese, keep any leftover pieces well wrapped separately from the main block. The exposed surfaces are vulnerable to mold growth.

Use Cheese Before It Expires

Consume your Parmigiano Reggiano within the recommended window for enjoyably fresh flavor. For best quality, use pre-grated Parmesan within two months and Parmigiano-Reggiano wedges within four months.

What If Parmigiano Reggiano Gets Moldy?

If you discover mold growth on your Parmigiano Reggiano, you may be able to save part of it. Here’s what to do:

Cut Off the Mold

Carefully trim away any moldy portions using a clean, dry knife. Cut at least 1 inch into the cheese beyond the edge of the visible mold to remove any roots. Throw away the moldy pieces.

Clean the Cheese

Wipe the freshly cut surface with a cheesecloth dampened lightly with vinegar to inhibit further mold growth. Pat dry.


Use new cheese paper or wrap to cover the cheese tightly. This protects the interior and prevents air exposure that could lead to more mold.

Enjoy Promptly

Eat the cheese within a week or two after encountering mold. Mold can leave behind bacteria that continue to grow.

When to Toss It

If the mold penetrates deep into the cheese, or you notice any off or sour flavors, it’s safest to discard all of it.

How to Keep Grated Parmigiano Reggiano from Molding

Pre-grated Parmesan and shredded Parmigiano Reggiano have a large surface area exposed to air. Here are some storage tips:

Get Smaller Bags

Once opened, transfer any leftover grated cheese to smaller airtight containers or bags. Limit air exposure to what you will use in a short time.

Avoid Moisture

Keep cheese dry and avoid introducing moisture from wet utensils or hands.

Keep Refrigerated

Always store grated Parmigiano Reggiano in the fridge. The cold temperature drastically slows mold growth.

Use Quickly

Use up any shredded or grated cheese within a month or two for best flavor and texture.

Check Before Using

Inspect grated cheese closely and smell before serving. Even refrigerated, mold can develop. Discard any with fuzz or an off smell.

Signs of Mold on Parmigiano Reggiano

Check cheese regularly for the following signs of mold growth:

  • White, blue, green, grey, or black fuzzy spots on the surface
  • Web-like mold tentacles between cheese crystals
  • Dry, pitted areas on the cheese rind
  • Ammonia-like odor
  • Soft or slimy spots

How to Store Parmigiano Reggiano Long Term

For the longest shelf life, consider these storage options:

Vacuum Seal It

Use a vacuum sealing machine to remove the air from around the cheese. This deprives mold spores of the oxygen needed for growth. Vacuum sealed, Parmesan can last around 10 months in the fridge.

Freeze It

Freezing stops mold growth and pauses ripening, extending the shelf life significantly. Wrap wedges very tightly in plastic wrap and foil. Frozen, Parmesan will keep for 6 months. Thaw in the fridge before use.

Coat It in Food-Safe Wax

Cheese wax provides an airtight seal against air and humidity. Wax-dipped Parmesan wheels can age for over 10 years. Use food-safe cheese wax, available online or at cheese making supply stores.

Buy Pre-aged Cheese

Look for Parmigiano Reggiano aged over 24 months. The naturally lower moisture content makes it less prone to mold over time. Properly stored, it can last over a year.

How to Use Parmigiano Reggiano with Mold

While it’s generally recommended to discard moldy cheese, some people use Parmigiano Reggiano with minor mold in cooking. Here are some considerations:

Evaluate the Level of Mold

If it’s just a small spot of mold confined to the rind, it may be fine to use in cooked dishes where the cheese gets fully heated. But deep or extensive mold is riskier.

Avoid Serving It Raw

Never use moldy Parmigiano Reggiano uncooked, such as shaved over pasta. Cooking is important to kill potential bacteria.

Look for Signs It Has Spoiled

Discard molded cheese if you notice any sour, ammonia-like, or unpleasant flavors developing.

Use Your Judgment

When in doubt about how much mold there is or how it could affect flavor, play it safe and throw it out.

Frequently Asked Questions

Does Parmesan cheese need to be refrigerated?

Yes, proper refrigeration is important for preventing Parmesan mold and maintaining quality. Store it wrapped in the fridge between 35°F and 40°F.

Can you freeze Parmesan cheese?

Yes, freezing stops ripening and mold growth. Tightly wrap wedges in plastic and foil. It will keep frozen for about 6 months.

How long does Parmigiano Reggiano last?

Stored properly in the fridge, Parmigiano Reggiano wedges will last around 4 months from the date of purchase. The rind may become inedible before the interior.

Can you eat moldy Parmesan?

It’s not recommended. Discard molded parts thoroughly. Remaining cheese should be cooked fully to kill bacteria before eating.

Can you get sick from eating moldy cheese?

Yes, some molds produce mycotoxins that can cause illness if ingested. Cooking doesn’t neutralize certain toxins. When in doubt, throw it out.

How can you tell if Parmesan cheese has gone bad?

Signs include mold growth, dark or discolored areas, drying or cracking, slimy texture, off odors, and bitter or sour flavor.


With proper storage and handling, it’s possible to keep Parmigiano Reggiano from developing mold and lasting for months. Keep it wrapped tightly, refrigerated at an ideal cheese temperature, and contained in a controlled environment. Inspect regularly for any fuzz or slimy spots and promptly remove affected areas. Discard cheese with extensive mold, sour odors, or funny textures to avoid safety issues or bad flavor. With the right care, you can continue enjoying the complex taste of fresh Parmigiano Reggiano.

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