Tahn

Ayran or Doogh and/or dhallë, dew, Jaree'a, leben, avamast, çiqilmast, mastaw, shaneena, or xynogala is a cold savory yogurt-based beverage popular across Central Asia, West Asia, Southeastern Europe, South Asia, North Asia and Eastern Europe. The principal ingredients are yogurt, water and salt. Herbs such as mint may be optionally added. Some varieties are carbonated. The Iranian variety is called doogh. Ayran in Chuvash: 'buttermilk') is mentioned in Mahmud al-Kashgari's 11th century Dīwān Lughāt al-Turk, although he did not give any information how ayran was made. The word is derived from the Old Turkic root adır- ("to separate"), cf. Turkish ayır- ("to separate").

Source: Wikipedia