Kvas is a traditional fermented beverage popular in Eastern Europe, particularly in Russia and Ukraine. It is made from rye bread, which is fermented with water, sugar, and sometimes fruits or herbs. The fermentation process gives kvas a slightly tangy flavor and a low alcohol content, usually around 0.5% to 1.5%. Kvas is often enjoyed as a refreshing drink, especially during the summer months. It can be consumed on its own or used as a base for soups and salads, such as Okroshka. Due to its unique taste and cultural significance, kvas is considered a staple in many Eastern European households.