Kvass is a beverage made by fermenting black or regular rye bread. It is considered non alcoholic, due to its low alcohol content, which typically is less than 1.2%. Kvass can also be flavored with fruits or herbs.
Kvass is popular in Russia and in the former Soviet republics of Belarus, Ukraine, Lithuania and Latvia, as well as some areas of China influenced by Russian culture. Kvass is sold in the streets during the summer, but now its sold packed year round.