Beet Kvas

Beet kvas is one of the oldest fermented drinks in the Slavic kitchen, dating back centuries before commercial probiotics became a wellness trend. Two ingredients, six days of patience, and you’ll have a deep red sour tonic that’s been used in Ukrainian and Russian homes as both a daily drink and a base for cold borscht.

The beauty of this recipe is what’s not in it. No starter, no whey, no sugar. Wild yeasts and bacteria already living on the beets and in the air do the work. Grating the beets exposes more surface area, which speeds the ferment and pulls out the deep magenta color faster than chunks would.

A warm spot is key. Cool kitchens slow the fermentation to a crawl and risk mold taking hold instead of the lactic acid bacteria you want. The recipe note about mold on the beets is accurate: a thin film on top is normal kahm yeast and skims right off. Anything fuzzy and colored should be tossed.

Pro Tips

• Use a non-reactive crock or large glass jar. Metal will react with the acid and ruin the batch.
• Cover with cheesecloth or a loose lid that allows gases to escape but keeps fruit flies out.
• Taste at day 5. The kvas is ready when it smells sour and tastes pleasantly tangy, not sharp or off.
• Keep the spent beets after straining and use them as a starter to speed up your next batch.

Variations

• Add a small piece of rye bread crust during the ferment for a richer, more complex flavor.
• Toss in a few crushed garlic cloves for a savory drinking vinegar style kvas.
• Use the strained kvas as the souring agent in a chilled summer borscht.