Home > The Unlikely Connection: Why Some Cheeses Smell Like Feet

The Unlikely Connection: Why Some Cheeses Smell Like Feet

Ever wonder why your fancy cheese smells like a gym sock? Here's the stinky truth, molecule by molecule.
Disclaimer: The visuals and narratives here invite you to explore the invisible world of scent. They blend science, symbolism, and imagination, and should be understood as interpretive, not factual depictions of real places or events.

Ever opened a box of fancy cheese and thought, whoa, feet? That powerful, earthy, maybe even a little funky smell isn't a mistake. It's the secret sign of a surprisingly delicious experience.

But how can something that smells like a sweaty sock taste so good? The answer is all about a tiny, hard-working bacterium.

A rustic wooden board featuring various stinky washed-rind cheeses like Limburger and Époisses, with their characteristic orange rinds.

A Tale of Two Stinks

The Star of the Show: A Bacterium

That cheesy foot-smell isn't a coincidence. The main culprit is a bacterium called Brevibacterium linens . This little guy lives on human skin and is a major reason feet get stinky. 1

The Foot-Cheese Connection: The same bacterium, Brevibacterium linens , is responsible for the characteristic smell of both sweaty feet and many pungent cheeses. Cheesemakers intentionally cultivate it to develop the unique aroma and rind of washed-rind cheeses.

In a weird twist, B. linens is the same bacterium cheesemakers use on purpose. It creates the reddish rind and funky smell on washed-rind cheeses, like Limburger or Époisses. 3 It’s a living bridge between a sweaty sock and your cheese board.

A Perfect Home (for Bacteria)

B. linens loves warm, moist, salty places. Think: the space between your toes inside a shoe. 1 Cheesemakers copy this exact environment through a process called affinage (aging).

A split-screen image comparing the moist environment between toes and the brine-washing process of a cheese wheel.

They repeatedly wash the cheese with a saltwater brine. This creates a perfect home for B. linens while kicking out other molds. 4 In both spots, on feet and on cheese, the bacteria eat nutrients and release smelly waste products.

The main one is isovaleric acid, the chemical that defines foot odor. 3 On feet, the bacteria get food (an amino acid called leucine) from sweat and dead skin cells. 1 On cheese, they get it from broken-down milk proteins. 11

Just Trying to Survive

Other bacteria, like Staphylococcus epidermidis , also help make isovaleric acid on feet. 8 Both environments can also produce sulfurous, "cheesy" smells from other compounds. 1

So why the smell? The bacteria make these stinky acids when they run out of easy-to-eat sugars and have to break down proteins for energy. 10 The stink is just their metabolic exhaust, a sign of them working hard to survive.

The Art of the Stink

The stink on a cheese is no accident, it's carefully crafted by a cheesemaker (or affineur ). This process of aging cheese is called affinage , and it's all about managing microbes. 7 For the smelliest cheeses, it all comes down to the washed rind.

A cheesemaker, known as an affineur, carefully washing a wheel of cheese with brine in a cool, dark aging cellar.

Washed Rinds: How to Grow the Funk

Washed-rind cheeses get their start after being pressed into a wheel. Then, they're repeatedly washed or smeared with a liquid solution over several weeks. 3

The wash, usually a saltwater brine, does two things. First, it kills off unwanted molds, like the white, fluffy stuff on Brie. 4 Second, the salty, wet surface is the perfect home for salt-loving bacteria, especially our friend B. linens . 4

This repeated washing ensures these "good" bacteria take over. They create that signature sticky, tacky texture and a pinkish-orange rind. 7 The cheesemaker is basically a microbe farmer, steering the cheese toward a very specific, funky goal.

Fueling the Funk: Breaking Down Protein

The cheesemaker sets the stage, but the cheese itself provides the food. The whole aging process relies on proteolysis, which is just a fancy word for proteins breaking down. 11

Enzymes from the milk and the rind's bacteria break down the cheese's internal structure (the "paste"). This breakdown from the outside-in is also why many washed-rind cheeses get so gooey and spoonable under the rind. 19

This process releases lots of free amino acids, including the leucine that B. linens turns into that stinky isovaleric acid. 12 More breakdown means more food for the bacteria, and more food means more funk.

A Field Guide to Famous Funk

The wash isn't always just brine. Cheesemakers sometimes add local booze to change the flavor and microbes. Here are a few famous stinkers.

A stylized photo showcasing four famous stinky cheeses: Limburger, Époisses de Bourgogne, Munster d'Alsace, and Taleggio.
Cheese Name Origin Washing Liquid Aroma Profile Contrasting Flavor Profile
Limburger Belgium/Germany Brine Famously compared to sweaty feet; intensely pungent and earthy. 26 Surprisingly mild; nutty, buttery, and sharp, especially when the rind is trimmed. 19
Époisses de Bourgogne Burgundy, France Brine and Marc de Bourgogne (a local grape brandy). 28 Powerfully meaty, "barnyardy," and pungent; famously banned on the Paris Metro. 26 Rich, salty, and creamy with a distinctive fruity and savory balance. 28
Munster d'Alsace Alsace, France Brine (rock salt and water). 33 Strong "barnyard" aroma, reminiscent of a well-used stable; powerful and savory. 26 Meaty and salty with a semi-soft, buttery texture; much milder than its aroma suggests. 26
Taleggio Lombardy, Italy Brine Described as wet grass, herbaceous, and having a body odor note that intensifies with age. 26 Mild, fruity, and slightly tangy with a creamy texture; surprisingly delicate. 19

Good Funk vs. Bad Funk

For newcomers, telling a fancy stink from a spoiled stink can be tricky. But the aromas that cheese fans love are easy to spot once you know what to look for. "Spoilage" here is more of a spectrum than a simple yes or no.

The Sign of Overripeness: Ammonia

A good, stinky foot or barnyard smell is what you want. That's the sign of a happy, well-aged cheese. 5 But what about a sharp, chemical smell? That's ammonia, and it means the cheese is past its prime. 37

This isn't from bad germs. It happens when the good bacteria on the rind start to die off at the end of their life cycle, releasing ammonia as a final... gift. 37 It's a natural part of the process, which is basically the controlled spoilage of milk. 5

Pro Tip: Beat the Ammonia: If you notice a faint ammonia smell on your cheese, don't throw it out just yet. Let it sit unwrapped at room temperature for 30-60 minutes. This can allow the gas to dissipate, often improving the flavor significantly.

An ammoniated cheese isn't dangerous, but it won't taste great. If it's just a faint whiff, let the cheese sit out for 30-60 minutes to "breathe." 37 If the smell is strong and won't go away, it's best to toss it.

True Spoilage: When to Toss It

Overripe is one thing, but truly spoiled is another. Here’s when to say goodbye to your cheese.

A comparison photo showing a healthy orange, tacky cheese rind next to a spoiled rind with slimy patches and black mold.

Training Your Brain to Love the Stink

The same molecule, isovaleric acid, can smell like gross feet OR delicious cheese. This proves we don't just smell with our nose, we smell with our brain. Liking stinky cheese is a victory of mind over matter.

Context is Everything

Your brain's perception of a smell is shaped by context and expectation. 40 The smell of vomit and Parmesan cheese share some key chemicals... the only difference is what you're looking at. 41

When you see cheese on a plate, your brain flips a "food" switch. It interprets the smell through a culinary lens, overriding your gut reaction to run away. 42 For a pro, years of good experiences have taught their brain that the funky smell signals a tasty, savory flavor is coming.

The Two Ways to Smell

The key to the stinky cheese paradox is understanding the two ways we smell.

  1. Orthonasal Olfaction: This is regular smelling. You sniff aromas from the air through your nostrils. This is your first impression of the stinky cheese on the cutting board. 43
  2. Retronasal Olfaction: This is the secret weapon. As you chew, smelly molecules from the food travel up the back of your throat into your nasal cavity. 43
A medical illustration of a human head in cross-section, showing the two pathways for smell: orthonasal through the nostrils and retronasal from the back of the throat.

Almost everything we call "flavor" actually comes from this second, retronasal path. 43 Your tongue only gets five basic tastes (sweet, salty, etc.). It's the thousands of aromas you get retronasally that let you tell an apple from a pear, or a nutty Gruyère from a meaty Époisses. 47

Smell vs. Flavor: The initial "stink" of a cheese is perceived through your nose (orthonasal). The complex "flavor" is perceived when aromas travel from your mouth to your nose as you chew (retronasal). This is why a cheese can smell challenging but taste delicious.

This two-path system solves the puzzle. The first whiff (orthonasal) might be off-putting. But when you eat it, your brain combines that same smell (retronasal) with the nice feelings of saltiness and creaminess from your mouth. 42

Your brain bundles it all together into one delicious "flavor" package. 44 Through experience, you learn that the "dangerous" smell is actually a sign of good, rich food, which lights up your brain's pleasure circuits. 41

The Stinky Conclusion

So, that foot-smell from your fancy Limburger isn't a mistake. It's a signature from the same microbes that live on our skin, connecting our bodies to our food. 1 It's the result of cheesemakers carefully guiding a living ecosystem on the rind. 4

And it's proof that our brains can learn to love almost anything. We can transform a smell that screams "danger!" into a signal for "delicious!" 41 It shows that the world, and the food on our plates, is as interesting as we're willing to find it.

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