Doogh

Ayran[a] is a cold savory yogurt-based beverage that is consumed across Central Asia, and the Balkans, in Turkey and Iran. The principal ingredients are yogurt, water and salt. Herbs such as mint may be optionally added. Some varieties are carbonated. Ayran (cf. airag in Mongolian: 'mare milk', uyran (уйран) 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