UPDATE: The most recent batches of the Original and Ginger Quas were canned on Mon 20th of May. Order now.

The Science of Kvass

At Quas, we combine both the historical 1000-years-old kvass making process and modern science.

The power of sourdough in every can

Quas is fermented using our proprietary 180-years-old sourdough culture. Compared to the baked sourdough bread, where all good bacteria are killed with heat, kvass preserves good bacteria alive.

Comparison of commercial and naturally produced unfiltered kvass
Quas is never filtered or pasteurised

Unlike commercial kvass you can find in shops, Quas has a cloudy appearance, which comes from billions of live beneficial bacteria.

When concentrated, the live cultures from 1 ml of kvass are visible without microscope

Each millilitre of Quas contains about 1.5 billion live bacteria

You don’t even need a microscope! Concentrated bacteria are visible to the naked eye.

We manually counted the number of live bacteria (CFU) in kvass

How do we know? Because we counted them!

By sowing droplets of Quas on a special growth medium, we can count the number of live bacteria also known as colony forming units (CFU).

visible colonies of lactic acid bacteria isolated from kvass
a can of kvass with a full glass of kvass in the background and grains scattered around

What is kvass?

Kvass is a 1000-year-old healthy non-alcoholic beverage made from fermented rye and barley


Original Quas

Mixed Pack Quas

Ginger Quas

Spiced Quas