We've been pondering the mystery of why some cheeses smell like stinky gym socks.

So we posed the question to our friends at St. James Cheese Company: Why do some cheeses smell bad...but, according to their devotees, taste delicious?

Most stinky cheeses are made in similar ways.

They're washed-rind cheeses.

After the cheese curds are placed in their wheels to age, washed-rind cheeses are bathed in salty brine, or sometimes booze.

Epoisses, the king of stinky cheeses, is washed in strong brandy.

It is washed in a solution of brine and marc de Bourgogne...it's a spirit that the winemakers will make there out of the grape must, right.

And it's a clear alcohol.

It's like jet fuel if you drink that stuff.

It's like really strong.

But they wash it with a solution that includes a little bit of the marc, and produces this wonderful small, it's about an eight or 10 ounce just a little stink bomb of gooeyness.

The washing process introduces salt and flavors from the brine.

It also brings in cheese's best friend: microbes -- although they can also be added in the form of starter cultures.

Washing creates a warm, moist, salty environment that certain microorganisms love.

And the star of stink is a bacterium called Brevibacterium linens.

Typically what happens is a cheese maker will wash the outside of the cheese with some kind of liquid, could be wine or beer or cider or a saltwater solution, and the moist salty wet on the rind attracts bacteria that's ambient in the air called Brevibacteria linens and the Brevibacteria linens colinate on the outside of the rind because they love that salty wet and they basically break down the protein that's on the rind and they emit gases.

Which does not sound appetizing, that sounds gross Incidentally, you know what else is warm, moist, and salty?

Sweaty human skin.

Close relatives of B. linens, like B. epidermidis, have been found on human feet.

which is the same type of bacteria which is in dark places on humans like feet and armpits and stuff like that.

That's why people are like why do my gym socks smell like cheese.

They are very closely related.

Microbes, mostly yeasts and molds, eat the fat and protein in the cheese and produce smelly compounds, including volatile fatty acids like propanoic acid and isovaleric acid.

Perhaps not coincidentally, those same compounds are implicated in foot odor.

Even worse, B. linens comes along and converts methionine, a sulfur-containing component of protein, to methanethiol, dimethyldisulfide, and dimethyltrisulfide.

Funny how every time we mention sulfur in a video about smell, we're about to tell you something stinks.

And yeah, methanethiol is in foot odor too.

It's probably not going to walk off the plate on you, I mean you probably have time to eat it before it moves.

You're not going to offend it by telling it that it smells bad.

It's going to be OK.

So it's not your imagination.

Stinky cheeses literally smell like feet.

B. linens isn't the only perpetrator.

It gets along great with other microbes in cheese, like the yeast Geotrichum candidum.

Some evidence suggests that bacteria and yeast work together to produce the distinctive pinkish-orange color of washed-rind cheeses, which is created by pigments called carotenoids.

And people learn to love these cheeses, despite or even because of their strong smell.

Once it hits your tongue, the meaty, salty flavor isn't much like feet at all.

But you kind of work up to it and you win because if the cheese didn't ultimately taste good after you put the stinky thing in your mouth, you probably wouldn't go back for more...But I think that's what makes cheese so fun The smell of Epoisses is so strong, some say it's banned on public transit in Paris -- though the stories are probably apocryphal.

I looked on the internet and couldn't find any confirmation of that.

When you smell it now, it's stinky, but a different kind of stinky.

It's a very biological stinky, not a chemical stinky, right?

It smells like hay to me...like if you put your face in a hay barn.

That's pure, just stink for the sake of being stinky.

Either way, people learn to love their stinky cheeses.

At first with certain stinky cheeses you smell them and you're like, why would anybody ever eat that, and the more you're around it, OK, it's not so offensive.

And then you notice you're excited about eating it and you like the funky taste and the funkier it is the more you want it.

Thanks for watching.

See you next week!