Is Blue Cheese Mold? Everything You Need to Know About Blue Cheese Safety

Blue cheese is a beloved delicacy known for its bold, tangy flavor and distinctive blue-green veining. While many cheese lovers enjoy this pungent variety, questions often arise about the visible mold in blue cheese and whether it’s safe to consume.

If you’ve ever wondered “is blue cheese mold?” or worried about the safety of eating cheese with visible mold spores, you’re not alone. Understanding the science behind blue cheese production and knowing how to identify when it’s gone bad can help you enjoy this flavorful cheese with confidence.

This comprehensive guide explores everything you need to know about blue cheese mold, from how it’s created to how to store it safely.

What Is Blue Cheese and How Is It Made?

Yes, blue cheese is indeed made with mold—but not just any mold. Blue cheese is crafted using specific cultures of Penicillium mold, which gives the cheese its characteristic appearance, aroma, and sharp taste.

The production process involves several carefully controlled steps:

• Milk preparation: High-quality cow’s, sheep’s, or goat’s milk is pasteurized and prepared for culturing
• Curdling: Starter cultures and rennet are added to form curds
• Mold introduction: Penicillium roqueforti or Penicillium glaucum spores are added to the curds
• Draining and forming: The curds are drained and formed into wheels
• Piercing: Stainless steel needles pierce the cheese to create air channels, allowing the mold to grow throughout
• Aging: The cheese ages for 2-4 months in temperature-controlled caves or rooms

During aging, the Penicillium cultures develop throughout the cheese, creating the blue and green veins that give blue cheese its name and distinctive appearance.

Is the Mold in Blue Cheese Safe to Eat?

The short answer is yes—the mold in blue cheese is completely safe for consumption. However, it’s important to understand why this particular mold is safe while other molds found on food are dangerous.

The Difference Between Good Mold and Bad Mold

The Penicillium species used in blue cheese production are carefully selected food-grade molds that do not produce harmful mycotoxins. These beneficial molds have been used in cheesemaking for centuries and are specifically cultivated for their safety and flavor-enhancing properties.

In contrast, molds that grow on food due to spoilage can produce dangerous compounds called mycotoxins. These toxic substances can cause various health problems, including digestive issues, immune system suppression, and in severe cases, long-term health complications.

Spoilage molds typically appear as fuzzy patches in white, green, black, pink, or grey and develop randomly on food surfaces. These are fundamentally different from the controlled, intentional mold cultures in blue cheese.

Health Benefits of Blue Cheese

Beyond being safe, blue cheese actually offers several nutritional benefits:

• Rich in calcium for bone health
• Contains protein for muscle maintenance
• Provides vitamin K2, which supports heart and bone health
• Contains beneficial probiotics that support gut health
• Offers conjugated linoleic acid (CLA), which may have anti-inflammatory properties

How Long Does Blue Cheese Last?

Proper storage is essential for maintaining blue cheese quality and safety. Understanding shelf life helps you enjoy your cheese at its best while avoiding spoilage.

Refrigerated Storage

When stored correctly in the refrigerator, blue cheese typically lasts:

• Unopened: 3-4 weeks past the printed date
• Opened: 3-4 weeks if properly wrapped
• Crumbled: 1 week after opening

Freezing Blue Cheese

You can freeze blue cheese to extend its shelf life significantly. While freezing may slightly alter the texture, making it more crumbly, the cheese remains safe to eat indefinitely when frozen at 0°F (-18°C) or below.

Tips for freezing blue cheese:

• Wrap tightly in plastic wrap, then aluminum foil
• Place in a freezer-safe bag or container
• Label with the date
• Use within 6 months for best quality
• Thaw in the refrigerator before use

How to Tell If Blue Cheese Has Gone Bad

Despite containing intentional mold, blue cheese can still spoil. Knowing how to identify spoiled blue cheese is crucial for food safety.

Visual Signs of Spoilage

Watch for these warning signs:

• Unusual mold colors: Pink, grey, or bright green fuzzy mold that looks different from the typical blue-green veining
• Excessive mold growth: Mold spreading dramatically beyond the normal veining patterns
• Slimy surface: A wet, slippery coating on the cheese surface
• Color changes: Brown, yellow, or darkened areas indicating oxidation or contamination
• Dried out appearance: Excessive cracking or hardening beyond normal aging

Smell and Texture Changes

Blue cheese naturally has a strong odor, but certain smell changes indicate spoilage:

• Ammonia smell: An overwhelming, harsh ammonia odor (mild ammonia scent is normal, but excessive is not)
• Rotten smell: A putrid or decaying odor distinct from the normal pungent aroma
• Bitter taste: An unpleasant, excessively bitter or off flavor

Risks of Eating Spoiled Blue Cheese

Consuming spoiled blue cheese can lead to foodborne illness with symptoms including:

• Nausea and vomiting
• Stomach cramps and abdominal pain
• Diarrhea
• Fever and chills
• Headache and fatigue

These symptoms typically appear within a few hours to a few days after consumption. If you experience severe symptoms, seek medical attention immediately.

Additionally, harmful molds that develop on spoiled cheese can produce mycotoxins that may cause more serious health issues with prolonged exposure.

Proper Storage Tips for Blue Cheese

Maximizing the shelf life and quality of blue cheese requires proper storage techniques:

Best Practices for Refrigeration

• Use proper wrapping: Wrap blue cheese in wax paper, parchment paper, or cheese paper first, then loosely in aluminum foil. This allows the cheese to breathe while preventing it from drying out
• Avoid plastic wrap: Direct contact with plastic wrap can trap moisture and promote unwanted mold growth
• Store in the cheese drawer: Keep blue cheese in the vegetable or cheese drawer where humidity is slightly higher
• Maintain proper temperature: Store at 35-45°F (1-7°C)
• Separate from other foods: Store blue cheese in a sealed container to prevent its strong odor from affecting other foods
• Keep it whole: Cut only what you need; larger pieces stay fresh longer

Handling Tips

• Always use clean utensils when cutting or serving
• Bring cheese to room temperature before serving for best flavor (30-60 minutes)
• Re-wrap cheese after each use
• Never leave blue cheese at room temperature for more than 2 hours

Can You Remove Mold From Blue Cheese?

This is a tricky question that depends on the type of mold you’re seeing.

If you notice a small amount of surface mold that appears different from the intentional blue-green veining (such as white or pink fuzz), some experts suggest you can cut away the affected area plus an inch around it. However, because blue cheese already has an internal mold structure throughout, spoilage mold may have penetrated deeper than visible.

The safest approach is to discard any blue cheese showing signs of unusual mold growth, especially if:

• The unusual mold covers a large area
• The cheese has an off smell
• You’re unsure whether it’s safe
• The cheese will be served to pregnant women, young children, elderly individuals, or people with compromised immune systems

Who Should Avoid Blue Cheese?

While blue cheese is safe for most people, certain groups should exercise caution or avoid it entirely:

• Pregnant women: Unpasteurized blue cheese may contain Listeria monocytogenes, which can cause serious complications during pregnancy. Pasteurized blue cheese is generally considered safe
• People with penicillin allergies: Those with severe penicillin allergies should consult their doctor, though most people with penicillin allergies can safely eat blue cheese as the proteins are different
• Individuals with compromised immune systems: Should consult healthcare providers before consuming any mold-ripened cheeses
• Those with histamine intolerance: Aged cheeses like blue cheese are high in histamine and may trigger symptoms

Popular Types of Blue Cheese

Different varieties of blue cheese offer unique flavors and textures:

• Roquefort: French sheep’s milk cheese with a sharp, tangy flavor; must be aged in specific caves in Roquefort-sur-Soulzon, France
• Gorgonzola: Italian cow’s milk cheese available in dolce (sweet/mild) and piccante (sharp/aged) varieties
• Stilton: English cow’s milk cheese with a rich, complex flavor and creamy texture
• Danish Blue: Milder, creamier cheese with a semi-soft texture
• Bleu d’Auvergne: French cow’s milk cheese with a strong, spicy flavor
• Maytag Blue: American artisan blue cheese with a balanced, less aggressive flavor

Frequently Asked Questions About Blue Cheese Mold

Can you eat the rind of blue cheese?

Yes, the rind of blue cheese is edible, though some people find it too strong or prefer to remove it for texture reasons. The rind is safe to consume as long as the cheese hasn’t spoiled.

Does blue cheese contain penicillin?

Blue cheese contains Penicillium mold, but not the antibiotic penicillin. The mold species used in blue cheese are different from those used to produce the antibiotic. Most people with penicillin allergies can safely eat blue cheese, but consult your doctor if you have concerns.

Why does my blue cheese smell like ammonia?

A slight ammonia smell is normal in blue cheese, especially as it ages. However, an overwhelming ammonia odor indicates the cheese is past its prime and should be discarded.

Can blue cheese make you sick?

Properly stored, fresh blue cheese is safe to eat. However, spoiled blue cheese or blue cheese contaminated with harmful bacteria can cause food poisoning.

Is blue cheese mold the same as bread mold?

No, the controlled Penicillium cultures in blue cheese are specifically selected for safety and flavor. Bread mold is random contamination from environmental mold spores and should not be consumed.

The Bottom Line

Blue cheese is indeed made with mold—specifically, safe, edible Penicillium cultures that create its distinctive appearance and flavor. This intentional mold is completely different from the harmful molds that grow on spoiled food.

The mold in blue cheese is not only safe but is an essential part of what makes this cheese special. However, blue cheese can still spoil, developing harmful molds and bacteria that can make you sick.

The key to safely enjoying blue cheese is proper storage and knowing how to identify signs of spoilage. Store your blue cheese wrapped in cheese paper or wax paper in the refrigerator, and discard it if you notice unusual colors, excessive fuzziness, slimy texture, or an overwhelming ammonia smell.

With proper handling and storage, blue cheese is a safe, nutritious, and delicious addition to your diet. Whether you enjoy it crumbled on salads, melted into sauces, or simply paired with crackers and fruit, you can feel confident that the mold in blue cheese is there by design—and perfectly safe to eat.

Sources:

• National Center for Biotechnology Information – Mycotoxins and Food Safety
• NCBI – Mold Growth on Food Products
• PubMed – Safety of Penicillium Species in Food
• NCBI – Blue Cheese Production and Characteristics
• Centers for Disease Control and Prevention – Foodborne Germs and Illnesses
• NCBI – Food Poisoning Symptoms and Causes
• U.S. Food and Drug Administration – Food Safety Guidelines