Less of a street food and more of a street drink, tuó năi is fermented camel milk. This unusual beverage—also called chal or shubat—was popularized in Central Asia and brought to Urumqi by the Kazakh people. Fermented camel milk is made by mixing fresh milk with a smaller sample of already fermented milk. More and more fresh milk is mixed in over three to four days and allowed to sour, at which point it is ready to serve. The drink is served ice cold (perfect for a hot day, I imagine). At a glance, you can see that this milk is frothy, thick, and brilliantly white. The first sip is a bit startling, as the fermentation has created a sparkling effervescence that bites at your tongue like carbonated water. It is sour and acidic, which only adds to the bite. There is a minor alcoholic taste to the milk, as well as very mild hints of citrus. You wouldn’t know it from the sound of it, but fermented camel milk is actually quite tasty and refreshing. Also, local lore claims that it has virus fighting abilities, so you’ve got going for you as well.
...which is nice.
The bottom line? For a delicious sample of Central Asian culture in China, you can’t go wrong with tuó năi.