White, crumbly, or even smelly, you can describe feta cheese however you like. Feta is one of the popular cheese in the US which you probably had tried before.
Like all other cheeses, feta comes with a mild acidic tang. Some people also described it as a foul or unpleasant smell (see my explanation and discussion here).
People even compared that to stinky feet, yeast, socks, or vomit…
In fact, the sour and rancid taste is a result of certain compounds produced by the bacteria living inside the cheese. As the bacteria breakdown the protein, some chemical compounds will be released in the form of gases. The particular chemical scents then got pick up by our smell receptors located in our nose, thus the bad smell.
The different type of cheese made in different place/region will have a different group of bacteria growing in it. So, the taste and smell will not be the same.
That’s why brie, feta, cheddar, blue-veined cheese like gorgonzola, Italy made real parmesan were all smell bad in their own way for a reason.
And cheese is never alone, there are other “smelly” fermented foods as well, e.g. the Chinese stinky tofu and Surströmming.
Which bacteria responsible for that?
Cheese houses tons of bacteria in it.
There are only some bacteria responsible for the bad smell, here is a list of bacteria in parmesan. One of which is the bacteria called Brevibacterium linens.
It lives on the surface rind of the cheese and gives off an awfully rancid smell. That’s why the rind of cheese normally gave you a stronger taste.
But, why is the smell so similar to the feet’s?
It’s because the notorious B. linen bacteria actually has cousin bacteria (same genus) called Brevibacterium epidermidis, which can be found in our sweaty skin, feet, intimate part, and armpit.
And yes, do not surprise that your feta cheese produces a similar bad smell just like your gym socks.
Mozzarella normally do not need a maturation period, so it will not give you that kind of smell/taste.
See my comparison of hard cheese provolone vs soft cheese mozzarella here.
Not just bacteria…
Joining the party there is yeast and mold, which feast on the protein and fat content of the cheese. Thus, producing smelly compounds like propanoic acid, methanethiol, and isovaleric acid.
These are the same compounds responsible for the foot odors.
One of the example for yeast is Geotrichum candidum.
Wait, do not get confused that the white spot (also mold) on your cheese is edible, no, they are not! Read my explanation here.
How to tell if feta has gone off?
So, we understand that feta is a fermented food where purposefully left out to let bacteria growing in them.
But, little did you know that without proper handling steps it will actually go off quite fast, e.g. if you can’t finish the cheese, and let them sit out for long. The surrounding microbes quickly join the feast, both good and the bad ones.
The bad ones can make
Therefore, the normal maturation/ aging room for cheese making has to be cleaned and strictly controlled.
So, back to the question above,
the fresh crumbled feta you bought from store should look neat, solid with a little crumbly. The taste comes with a little natural sourness, salty, umami (a little bitter), tangy, and creamy.
They shouldn’t be gluey, slimy, sticky or even moldy.
The feta skin has to look clean and bright, similar to tofu but with a bit of texture and without any kind of black/white/yellow spots on it.If the feta is off, it normally is overly sour and has a strong unpleasant smell.
How to keep feta cheese fresh
Soft cheese is delicious, but aren’t known for longevity.
Crumbled feta for example, has a produced-to-expired period anywhere from 2 weeks to 6 months, depends on how it packaged. Those that are in brine can last a bit longer if unopened.
Because of high moisture, feta cheese can get contaminated and gone off pretty quickly compared to hard cheese, See comparison here.
To store your feta cheese correctly:
- Finish them within 3-5 days (refrigerated) after opening.
- Never leave out feta in room temperature for long, throw them away.
- Never put the excess feta back to the brine water (package). Take feta out, close it, put back to fridge.
- If it’s a cut feta block, you can make your own brined water for leftover/unbrined feta. Simply dissolve 2 tsp of kosher salt in 2 cups of water. Then, seal and refrigerate the container.
- Check for signs of spoilage, e.g. mold and black dots.
If there is visible mold spots, it’s very possible that the whole cheese had already been contaminated. Scrapping them off will not work in soft cheese, you should just discard them instead.
Hey wait, take 1 minute read through these important symptoms allergic to feta I wrote last week.