Boza is a traditional cold, thick drink that originates from Central Asia, but also common in several Balkan countries. It is fermented bulgur (a kind of wheat) with sugar and water additions. Vefa Bozacisi is the most known and traditional producer of boza in Istanbul. In Ankara, you get excellent Boza from Akman Boza Salonu in the old city in Ulus. Boza can also be found on the shelves of many supermarkets, especially in winter, packaged in 1-litre PET bottles. However these bottled bozas lack the sourness and consistency of traditional boza, they are sweeter and less dense.