Kashk (Persian: کشک, Arabic: كشك, Kurdish: keşk, Turkish: keş peyniri), qurut (Kazakh: құрт, Turkmen: gurt, Uzbek: qurt, Azerbaijani: qurut, Bashkir: ҡорот, Kyrgyz: курут, Pashto: قروت, Turkish: kurut, sürk, taş yoğurt, kurutulmuş yoğurt, Shor: қурут), chortan (Armenian: չորթան, [chor, meaning "dried", plus tan]), aaruul (Mongolian: ааруул) is a range of dairy products used in cuisines of Iranian, Kurdish, Turkish, Mongolian, Central Asian, Transcaucasian, and the Levantine peoples. Kashk is made from drained yogurt (in particular, drained qatiq) or drained sour milk by forming it and letting it dry. It can be made in a variety of forms, including rolled into balls, sliced into strips, and formed into chunks.
There are three main kinds of food products with this name: foods based on curdled milk products like yogurt or cheese; foods based on barley broth, bread, or flour; and foods based on cereals combined with curdled milk.
Kashk is a sort of gruel of fresh cheese. It is eaten plain, but can be used other ways. For example, it can be dissolved in water and eaten like yogurt. In western parts of Azerbaijan, it's customary to dissolve qurut in water by hand and use the sauce with xəngəl, the traditional Azerbaijani lasagna-type dish. Qurut dissolved in water is a primary ingredient of qurutob, a traditional Persian dish in Tajik, Afghan and Iranian cuisine and thought of by some as the national dish of Tajikistan. One of the main dishes in Afghanistan is kichree qurut, made with mung beans, rice and qurut dissolved in water. It is sometimes salted, and in Inner Mongolia can be flavoured and distributed as candy.
Chortan is mentioned in the Armenian epic poem, Sasuntsi Davit, as an oral tradition dating from 8th-century, which was first put into written form in 1873. Chor means dry in the Armenian language. Kashk is also mentioned in the 10th-century Persian book of poetry Shahnameh. Khoshk (Persian : خشک meaning "dry") which indicates that the kashk or kishk is prepared through a drying [خشکیدن] process. Qurut or kurut means dried in Turkic languages.
In modern Iran, kashk is a thick whitish liquid similar to whey or sour cream, used in traditional Persian and Kurdish cuisine, like ash reshteh, kashk e badamjan, kale joush. It is available as a liquid or in a dried form, which needs to be soaked and softened before it can be used in cooking. Kashk was traditionally produced from the leftovers of cheese-making (more specifically, the milk used to make it). The procedure is, subtracting butter from milk, the remainder is doogh which can be used as the base for kashk. The water is subtracted from this whitish beverage and what remains is kashk which can be dried. Iranian kashk has made an appearance in US markets in the past half-century by several Iranian grocers starting with Kashk Hendessi.
In Turkey, kashk is a dried yoghurt product also known as keş peyniri, kurut, taş yoğurt, kuru yoğurt, or katık keşi. Its contents and production vary by region. In western and northern Turkey, especially in Bolu, the product is categorized as a cheese owing to its shape and white color. In eastern Turkey, especially Erzincan, Erzurum, and Kars, kurut is produced from skimmed yoghurt made from the whey left over from production of butter by the yayık method, and then crushed or rolled. In parts of southeastern Turkey with a significant Kurdish population, it is called keşk. All versions of this dairy product are salty. It is used as an ingredient in soups, keşkek, erişte, etc.
There is also a closely related dried food product called tarhana which is based on a fermented mixture of grain and yoghurt or fermented milk. It is very similar to kishk of the Levantine cuisine described below.
In Lebanon, Palestine, Arabian Peninsula and Syria, kishk is a powdery cereal of burghul (cracked wheat) fermented with milk and laban (yogurt), usually from goat milk. It is easily stored and is valuable to the winter diet of isolated villagers or country people. Kishk is prepared in early autumn following the preparation of burghul. Milk, laban and burghul are mixed well together and allowed to ferment for nine days. Each morning the mixture is thoroughly kneaded with the hands. When fermentation is complete the kishk is spread on a clean cloth to dry. Finally it is rubbed well between the hands until it is reduced to a powder and then stored in a dry place. In Jordan a dried yogurt similar to kashk called jameed is commonly used. Elsewhere in the Levant, similar products are referred to as drained labneh (labneh malboudeh).