Parmesan cheese is a hard Italian cheese that is often grated over pastas, risottos, and other dishes to add a salty, nutty flavor. With its low moisture content and hard texture, Parmesan cheese is known for its long shelf life compared to softer cheeses. But does Parmesan cheese last forever in the fridge or does it eventually go bad?
The short answer is that yes, Parmesan cheese can go bad in the fridge if stored for too long. However, Parmesan cheese tends to last longer than many other cheeses due to its low moisture content and aging process. With proper storage, Parmesan cheese can often last in the fridge for several months past the ‘best by’ date printed on the packaging.
Below we will look in more detail at how to tell if Parmesan cheese has gone bad, how long it lasts in the fridge, and the best way to store Parmesan to maximize its shelf life and avoid waste.
How to Tell if Parmesan Cheese Has Gone Bad
There are a few common signs that indicate Parmesan cheese has spoiled and is no longer safe to eat. Here’s what to look for:
– Mold growth. Mold on hard cheeses like Parmesan appears fuzzy or dry and can range in color from white to green to blue. Any mold at all is a sign the cheese should be discarded.
– Unpleasant odor. Fresh Parmesan has a distinct nutty, savory smell. Spoiled Parmesan will have an unpleasant sour or ‘off’ odor.
– Odd flavors. Bad Parmesan tastes bitter, acidic or ‘moldy’. There should be no unpleasant flavors.
– Discoloration or dryness. Good Parmesan is pale yellow and glossy. Spoiled Parmesan may be more greyish, yellowish-brown or chalky looking.
– Soft spots or sliminess. Fresh Parmesan has a hard, crumbly texture. Soft spots or sliminess indicate spoilage.
– Presence of gas holes. Gas bubbles and holes can be a sign of fermentation and spoilage. Fresh Parmesan may have small holes but should not have gas pockets.
If your Parmesan exhibits any of these signs, it has likely spoiled due to mold growth or bacteria and should be discarded. Relying on sight and smell is the best way to determine if your Parmesan cheese has gone bad.
How Long Does Parmesan Cheese Last in the Fridge?
So how long can you keep Parmesan cheese past its printed ‘best by’ date if stored in the fridge? Here is a general guideline for Parmesan shelf life in the refrigerator:
– Unopened Parmesan: 12 months
– Opened Parmesan wedge: 3 to 6 months
– Grated Parmesan: 2 to 3 months
Of course, these timelines can vary based on how well the cheese has been stored and handled. Properly stored Parmesan can often last for several weeks or even months beyond these timeframes before going bad.
The most important factor in maximizing Parmesan’s fridge life is ensuring it is properly wrapped to prevent moisture loss and contamination. An unopened Parmesan wedge still sealed in the original packaging will keep the longest. Once opened, Parmesan should be tightly wrapped in plastic wrap or wax/parchment paper and placed in a sealed container.
Grated Parmesan has a shorter shelf life than Parmesan wedges because it has more surface area exposed to air. Make sure to press out all the air in the container or bag before sealing and storing grated cheese.
Always rely on your senses – if the Parmesan smells, tastes and looks okay, it should still be fine to use even past the ‘best by’ date. But once it shows any signs of mold or spoilage, it must be discarded.
Tips for Storing Parmesan Cheese
Storing Parmesan cheese properly is key to extending its shelf life and preventing waste. Here are some useful tips for keeping Parmesan fresh in the fridge:
– Purchase smaller wedges. Smaller Parmesan pieces have less surface area exposed to air, slowing moisture loss and mold growth. Opt for wedges around 1/4 to 1/2 pound.
– Keep Parmesan wedges whole for as long as possible. Cut off only what you need then immediately rewrap the wedge.
– Wrap tightly in plastic wrap or parchment paper. Make sure the cheese has no air pockets before refrigerating. Change the wrapping if it becomes torn or dirty.
– Use a zip top bag for grated Parmesan. Press out excess air before sealing to prevent moisture loss.
– Store Parmesan in the coldest part of your fridge, not in the door. The back bottom shelf is ideal.
– Keep Parmesan away from high-moisture ingredients like fresh produce that could cause it to mold faster.
– Avoid introducing contaminants like dirty utensils or hands into the cheese. Always use clean knives and forks when removing Parmesan for use.
– Don’t wash Parmesan rinds. Washing introduces excess moisture that speeds up mold growth. Simply scrape off any surface mold.
– If Parmesan grows mold, cut off at least 1 inch around and below the moldy spot and rewrap the remaining wedge.
Following proper storage methods helps prevent Parmesan cheese from drying out or growing mold in the fridge. With the right care, Parmesan can stay fresh and usable for many months past the ‘best by’ date.
What Happens If You Eat Parmesan Cheese Past Its Prime?
It is best to throw away Parmesan cheese once it shows any signs of spoilage like mold, sour smell, changes in taste or texture, etc. Eating spoiled Parmesan can potentially cause foodborne illness.
However, if the cheese only has slight drying or aging defects like little flavor, harder texture or pale color, it is generally still safe to consume but may not taste very palatable. You are unlikely to get sick from very slightly ‘off’ Parmesan but it will not have an optimal flavor.
Use your best judgment – Parmesan that has extensive mold growth, foul odors or very unusual textures could make you sick and should always be discarded. With hard cheese like Parmesan, a small amount of surface mold can be safely cut off but deep or extensive mold is risky. If in doubt, do not eat it.
Some signs that Parmesan has gone too far past its prime to eat safely include:
– Fuzzy mold covering a large surface area
– Mold growing below the cheese surface more than 1/4 inch deep
– Very soft, slimy texture
– Strong rotten, sour or putrid smell
– Ammonia-like odor
– Extremely bitter taste
– Orange, red, blue or black mold colors
Consuming Parmesan with these extensive spoilage defects could potentially cause food poisoning or gastrointestinal issues. You cannot salvage Parmesan that is badly moldy or decomposed. When it doubt, remember it’s better to be safe than sorry and discard Parmesan that looks or smells questionable.
Can You Freeze Parmesan Cheese?
Freezing is an excellent way to extend the shelf life of Parmesan cheese beyond the typical fridge timelines. Properly frozen, Parmesan can keep for 6 months or longer without sacrificing flavor or texture.
To freeze Parmesan:
– Cut the wedge into smaller portions or buy pre-cut cheese blocks. Smaller pieces freeze more efficiently.
– Wrap the pieces very tightly in plastic wrap, squeezing out all air. Then wrap again in aluminum foil or place in freezer bags.
– Label bags with the date and Parmesan variety. Sharpie markers write well on foil.
– Freeze for up to 6 months. If freezing longer, check occasionally for freezer burn.
– Thaw overnight in the refrigerator before use. Let come to room temperature before unwrapping.
– Use thawed Parmesan within 1 week for peak freshness. Do not refreeze.
– Avoid freezing already grated Parmesan. It can become gummy in texture when thawed. Freeze wedges then grate as needed.
Well-wrapped, frozen Parmesan stays fresh tasting for as long as 6 months. Freezing prevents mold growth and slows down aging so you can enjoy Parmesan past its fridge life.
Frequently Asked Questions
Does Parmesan cheese need to be refrigerated?
Yes, Parmesan should always be refrigerated for food safety after opening. Cold temperatures prevent microbial growth and slow moisture loss. Leave Parmesan wedges at room temperature only briefly when using then promptly return to the fridge.
Can moldy Parmesan cheese make you sick?
Yes, eating Parmesan with mold can potentially cause illness from bacteria or mycotoxins. Discard Parmesan immediately if it has any mold, even just surface mold. The mold roots can run deeper into the cheese. Do not try to salvage Parmesan with visible mold.
Can Parmesan cheese be frozen?
Yes, Parmesan freezes very well for 6 months or longer when properly wrapped. Freeze in small portions then thaw overnight in the fridge before using. Grated Parmesan does not freeze as well.
What happens if you eat expired Parmesan?
If it is only slightly expired, Parmesan is generally still safe to eat but may be more dry or less flavorful. However, Parmesan with extensive mold or foul odors can potentially cause food poisoning and should always be discarded no matter how long ago it expired.
How can you make Parmesan cheese last longer?
– Buy smaller wedges and keep Parmesan whole as long as possible
– Tightly wrap cut wedges in plastic wrap or parchment paper
– Store Parmesan in coldest part of fridge away from high-moisture foods
– Do not introduce excess moisture by washing rinds or double-dipping utensils
– Cut off any mold at least 1 inch around the spot
– Freeze for long-term storage
Can you cook with expired Parmesan?
In most cases, it is safe to cook with Parmesan that is sightly dried out or past its ‘best by’ date, as long as it shows no visible mold growth. The heat from cooking makes it safe. However, the flavor of expired Parmesan in cooked dishes may be inferior.
Conclusions
Parmesan cheese can go bad in the fridge after an extended period of storage, generally 3-6 months for opened wedges and 2-3 months for grated. Proper storage is key – keep Parmesan tightly wrapped, avoid moisture exposure, and store in the coldest part of the fridge to maximize its shelf life.
Look for signs of mold growth, unpleasant odors, odd textures or colors to determine if your Parmesan has spoiled. Discard Parmesan at the first signs of spoilage as consuming bad cheese can cause foodborne illness. With proper handling, Parmesan often keeps well for many months past the ‘best by’ date printed on the packaging.
Freezing Parmesan for up to 6 months can also extend its shelf life if you want to keep it longer term. Follow the storage and freezing guidelines provided and your Parmesan cheese should stay fresh and usable for a long time before it goes bad in the fridge.