• Wed. May 31st, 2023


Worldwide Gastronomy Habits & Trends

Zsiadłe mleko, kożuch and żętyca: discovering udder-ly weird dairy products and dishes from Poland

ByDaria Malinowska

Dec 14, 2022

Nobody knows for sure who and why decided to milk an animal for the first time. According to some sources, raw milk became a part of our diet around 8-10 000 years ago. This is when people learned that a mother’s milk is a complete and nutritious food that can sustain lives like no other, no matter the species. During this time, we managed to come up with a plethora of ways how to consume dairy. And some are weirder than others.

If I were to point out three curious dairy products popular in Poland, they would be zsiadłe mleko (sour milk), kożuch (milk skin), and Żętyca. Try them, if you dairy.

Sour milk

We will probably never know when and who discovered that spoiled milk tasted good taste as well as had a quite long shelf life, but it is safe to say that it was a very long time ago. Some may even say that sour milk was the first dairy product in human history. However, the original fermentation of milk was more inevitable rather than desired. At least at first.

Zsiadłe mleko (curdled milk), kwaśne mleko or (sour milk), as some people refer to it, is kind of “self-born”. The whole process called lactic fermentation occurs spontaneously because of the lactic bacteria that naturally exist in the milk.

Therefore, the only things needed for it to form are milk, time, and temperature. For the Neolithic people, it was a blessing and a curse: spoiled milk lasted longer, true, but the process was also hard to stop. Nowadays, it would be enough to leave raw milk (but not UHT!) out of the refrigerator for a day or two to watch it sour and, after that, split into two parts – thick and liquid. When you mix them together, you get sour milk.

You could also consume them separately: drink the whey (liquid) like a beverage and use the thick curd mass to create quark (but you would have to heat it and filter it through the gauze first).

In Poland, milk was traditionally soured without human intervention. Sometimes, people would accelerate the fermentation process by adding a bit of animal rennet, a piece of lead, a flint, or even a coin to the vessel.

Most commonly, sour milk is simply drunk or served as a side with potatoes. It is also a vital ingredient in chłodnik, a beetroot soup popular in Poland.

Kożuch (Milk skin)

Who has not had the questionable pleasure of encountering milk skin, the very thin membrane that forms on hot milk? The majority would probably exclaim with horror that this is one of the most disgusting things (and I second that!).

However, if there are any milk skin aficionados reading this, you may be interested in eating a slice of bread covered with this atrocity and sprinkled with sugar. It used to be a treat for children in Poland.

If you want to use the milk skin up somehow, and the texture is too revolting for you, you can always add it to your cookie batter! More adventurous cooks could try to recreate dishes proposed by fancy Polish chefs who attempted to demystify this membrane of sorrow, such as milk skin with herring in cream with onion chutney.


If you are feeling brave, you can also try żętyca (sometimes spelled żentyca) in the south of Poland. It is a drink inextricably intertwined with the history of sheep grazing and the tradition of the Podhale region. The fact that this liquid is not just thrown away also fits in with the waste not, want not philosophy.

It’s sheep milk whey with rennet, a byproduct achieved during the production of oscypek and bunc, traditional highland cheeses. Interestingly, in the 19th-century people consumed this liquid as a medicine for respiratory ailments.

Żętyca tastes best chilled. The fresher it is, the sweeter its taste. The smell is quite strong and… not for everybody. Moreover, consuming it in big amounts at once may upset your stomach. Careful should be especially those not used to dairy products or suffering from lactose intolerance.

Hungry for more interesting facts from the culinary world? Check our main page.