Mold On Cheddar Cheese: Is It Safe To Eat?

Cheddar cheese is a staple of many households, its versatility allows it to be used to enhance many dishes and is one of the world’s most popular types of cheese.

So, what do you do when you go to your fridge, take out your cheddar to use in your next meal, and find it has patches of mold on it? Is the cheese still safe to eat, what kind of mold is growing and can you scrape off the moldy parts and use the rest?

In this article, we will be answering all these questions and more, so, for all you need to know about mold on cheddar cheese, keep reading.

is moldy cheddar cheese safe to eat

Why does cheddar cheese grow mold?

Mold will grow on any organic material as long as the conditions are right, all it needs are a source of moisture, nutrients, and the correct temperature ranges.

It’s true that cheddar cheese has a lower water content than other types of cheese, such as cream cheese, however, moisture in the refrigerator itself or within the packet the cheese comes in is ample for mold to be able to grow.

Fluctuations in temperature from frequently opening and closing the door, raising the overall humidity in the refrigerator by storing items before they have cooled down and broken gaskets are all common reasons that you may find your cheddar cheese is beginning to grow mold faster than you would expect.

Improperly storing your cheese is the number one cause of mold growthOpens in a new tab. occurrence. The ideal temperature range to store your cheddar cheese is between 42-46 degrees Fahrenheit. Even small fluctuations above this temperature range can cause mild to begin to grow rapidly.

What types of mold grow on cheddar cheese?

Penicillium is the strain most commonly associated with growth on cheddar cheese. It is one of the most commonly found strains of mold (with over 400 described species), found growing on food products and within properties.

The three most common individual strains of penicillium mold are penicillium roqueforti, penicillium glaucum, and penicillium candidum.

Are the molds dangerous?

Penicillium strains do have the ability to produce mycotoxins as a defense mechanism whenever they feel threatened or if it is disturbed in any way.

The number of spores you would be subjected to from mold growing on cheddar cheese would be very small, lessening the chance of any major symptoms for healthy individuals.

However, people with suppressed immune systems or allergic asthma should be cautious of any molds, as they could cause a reaction. In this example, the following symptoms could occur:

  • Runny nose
  • Wheezing
  • Nausea
  • Vomiting
  • Gastrointestinal discomfort
  • Skin irritation

Bacteria grows in similar conditions to mold, so this is also something to consider. Even otherwise healthy individuals can suffer from food poisoning if they ingest cheese with high levels of bacteria that could be present along with the mold.

What does mold on cheddar cheese look like?

Mold growth on cheddar cheese is fortunately fairly easy to spot. The penicillium strain presents itself as circular patches of blue-green growth with velvet or powdery texture.

Bear in mind that mold can begin to grow rapidly under the correct circumstances, and may not be visible to the naked eye until several days whilst it is in its first stages. This means there could well be mold spores that have settled on the cheese and begun to create a colony without you being able to see them.

Other signs that your cheddar is beginning to grow mold and become bad in general, is that it will form a hard outer layer, become dry, and develop cracks. There will also be a strong unpleasant smell and discoloration of the cheese that accompanies this.

What does mold on shredded cheddar look like?

Finding mold growing on shredded cheddar cheese can be tricker than on a block, as there is not one clear surface to inspect.

Instead, what you may notice is the clumping together of the cheddar strands and some hints of blue coloration within these clumps.

A rancid smell is another strong indicator that mold has begun to grow within the cheese and may be the first thing you notice when you open the bag.

What is the white fluffy mold that grows on cheddar?

The white mold with a fluffy texture that you see growing on cheddar is likely to be one of two things.

It could be a strain of penicillium mold, as this often appears as a white growth with a powdery to fluffy texture that gradually turns blue over time.

Or, it could not be mold at all and instead could be made up of calcium lactate crystals, which are completely harmless and a signal of a well-aged cheese. They will slightly alter the texture of the cheese, but the flavor will be greatly enhanced if these are present.

What is the orange mold on cheddar?

Sporendonema casei is the probable cause of orange-colored mold on your cheddar cheese, and this should cause little concern as it is a harmless mold strain that is present on many cheese rinds that add to their characteristics and flavor profiles.

Should you still not want to risk eating the mold, you can safely cut the affected away from the cheese and eat the rest, making sure to cut at least 1 inch away from the affected area.

Can you cut off the mold on cheddar cheese and eat the rest?

Mold can be cut away from hard cheeses such as cheddar, as they cannot grow their root systems down into the deeper parts of the cheese as easily as with soft cheeses.

To be certain that you are removing all the mold, cut 2.5cm (1 inch), away from the affected area with a clean knife. Do not be tempted to scrape the mold away, as this can spread its spores over the remaining cheese.

A caveat to this is if you suffer from allergies, allergic asthma, or have a suppressed immune system if this is the case, you are better off not risking any symptoms and should discard the cheese instead.

What happens if you eat moldy cheddar cheese?

In most cases, nothing. Unless the cheese is very badly affected by mold, eating a small amount would likely cause little harm.

If the cheese were badly affected by mold, it would often be accompanied by an unpleasant smell that would make it unappetizing, so in this case it would be best not to consume it.

There is the possibility of allergic reactions in those sensitive to the strain of mold that were growing, and if you suffer from this and experience symptoms after accidentally eating moldy cheese, you should contact a medical professional.

The issue would not only be with mold, however, as when mold is found growing on cheese, there is a strong possibility that bacteria is also present, and harmful strains such as E. coli can accompany mold, and if consumed can cause food poisoning.

How fast does cheddar cheese mold?

Mold grows on cheddar cheese exceptionally quickly if the conditions are correct. For example, if there is adequate moisture and the temperature reaches greater than 60 degrees Fahrenheit (room temperature), mold can begin to grow within only a few hours.

As cheddar cheese has a lower water content than soft cheeses, it will grow significant amounts of mold more slowly, however, if left out at room temperature for several days, large quantiles of visible mold growth would appear on its surface.

How to prevent mold on cheddar cheese

Prevention is the best cure in regard to dealing with mold growth in cheddar cheese, and one of the best ways that you can prevent mold from growing is to ensure that you are storing it correctly. With that in mind, here are several tips to store cheddar cheese that will increase its shelf-life considerably and help to prevent mold growth.

Wrap in parchment paper

After portioning out the cheddar you want to use, instead of putting it back in the plastic wrapping it may have come in, wrap it in a piece of parchment paper.

Parchment paper will prevent cross-contamination of other items in the fridge and will allow the cheese to breathe whilst absorbing the moisture directly around it.

Reducing the moisture on the cheese itself makes it less a hospitable environment for mold to grow on.

Store in the vegetable crisper

The vegetable crisper is one of the lowest humidity areas of the refrigerator and so further helps to reduce the odds of mold growing on your cheddar by removing one of the key resources it needs.

It is also subject to fewer temperature fluctuations, as being kept within a drawer protects it from waves of warm air when the fridge door is opened.

Check your refrigerator seals

Seals (called gaskets) around the edges of the refrigerator doors help to keep warm air out and cool air trapped inside, maintaining its temperature.

Over time the rubber in these seals can perish and become damaged which can cause temperature fluctuations and put additional strain on the motor to maintain the temperature set on the thermostat.

These small temperature fluctuations can cause your cheddar to dry out and if the temperature is too high for too long, can increase bacteria and mold growth.

Portion out before you let cheese “breathe”

Taking cheddar cheese out of the refrigerator to allow it to come to room temperature and “breathe”, is an excellent way to enjoy its complex flavor profiles.

If this is your preferred way to enjoy cheddar cheese, consider portioning out what you will use and put the rest of the cheese back in the refrigerator.

The reason for this is that if you are using a large block of cheddar, each time it comes to room temperature, bacteria, and mold can begin to multiply. Putting it back in the fridge will put these bacteria and molds into a state of hibernation, but will not kill them, so mold and bacteria will grow each time this occurs, making it more likely that they grow to the extent where they are likely to spoil the cheese and cause illness.

Store it in a paper bag

Cheesemongers often package their cheeses in plastic wrapping, this is because they will sell a large portion of their stock fairly quickly, and it will not be in this wrapping for long.

Cheese experts state that if you want to improve the shelf-life of your cheddar without spoiling the cheese with a “plastic taste”, wrap the cheese in parchment paper as previously suggested, and then store it in a paper bag.

The bag will allow air to circulate, which cheese needs to keep its characteristic textures and taste, whilst preventing cross-contamination and preventing mold spores from finding their way onto the product.

Add a sugar cube to the container it is stored in

An additional method to keep the moisture level low enough to prevent mold and bacteria growth on your stored cheddar is to place a sugar cube in the paper bag you have stored it in.

The sugar cube will absorb excess moisture from the cheese without drying it completely, making it less appealing to mold and bacteria.


Cheddar cheese grows mold at a slower rate than soft cheeses due to having a lower moisture content, however, mold can still form. The most common mold found growing on cheddar is penicillium, which is unlikely to cause health issues to healthy individuals in small amounts, but can be an issue for those with suppressed immune systems or allergies.

The best way to prevent mold growth on cheddar cheese is to ensure you are storing it correctly by keeping it at 40 degrees Fahrenheit or less whilst wrapped in parchment paper, as well as keeping it in a paper bag in the vegetable crisper.

Chris Walker

Chris Walker has struggled for several years with mold after buying his own property. After finding the solutions to several issues around his home, he decided to create this site in order to answer as many questions about mold and mildew as possible to help others dealing with the same problems.

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