Made from dark or light rye bread, kvass is sometimes referred to as "the bread drink." It is a fermented beverage which contains approximately 1 percent alcohol. It is popular in Russia and many other Eastern European countries, where it is often sold on street corners.
There are two different ways that kvass is regularly served: filtered and unfiltered. Some prefer that the brew have the yeast filtered out of it, while others choose to have the yeast remain. When the yeast is allowed to remain, it gives the drink a stronger taste and a deeper hue.
Kvass is produced commercially, but it is also often made at home. When made commercially, it is not uncommon for not only rye bread to be used but also wheat or pumpernickel breads to be added. Using only rye bread, however, gives the kvass a very unique taste.
When made at home, the process is a simple one. Pieces of rye bread are torn into tiny bite size pieces, dried until they are crisp, and then placed into a pot. Boiling water is poured over the bread, and the mixture is allowed to stand at room temperature until the fermentation process begins. After a day or so, the liquid is strained and yeast and honey or sugar is added to sweeten the brew. These ingredients must be allowed to sit for approximately 10 to 12 hours, before they are refrigerated.
For flavor, there are a number of different ingredients that are added to this traditional brew. Some people add crushed mint leaves for a refreshing twist, while others add a splash of fruit juice or even small chunks of fresh fruit. Berries or raisins are also popular additions; often, the raisins are allowed to soak for a time in the kvass before it is served, not only to sweeten the drink but to flavor add a unique and deeper flavor. No matter what flavoring may be added, kvass is best served well chilled.
Centuries ago kvass was considered a peasants' drink. In modern times, it is popular throughout most European countries and the manufacturing of the drink is a multimillion dollar industry. Once only a drink served in summer, this tawny colored beverage is now served year-round in most places, along side other soft drinks and colas.