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Beet kvass
Level 1 · beginner
Cubes of raw beet in brine. You don't eat the beets; you drink the brine, deep red, salty and sour.
- Salt
- 2.5% 25 g per liter of water
- Time
- Up to 7 days
- Temperature
- 60–70°F
- Jar
- 2L
The golden rule: all the beets under the brine and never less than 2% salt over the water.
No sign-up. We guide you step by step, from the scale to the fridge.
Reviewed October 26, 2026 · 44 facts, each with its source
You'll need
- 2-liter glass jar (about half a gallon)
- Glass weight, or a sealed freezer bag filled with brine
- Airlock lid or a regular lid
- Kitchen scale
- pH strips or a pH meter
- Strainer
- Clean bottles or jars with lids
Step by step
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Wash the beets and cut them into cubes
Wash the jar, the weight and the cutting board in hot soapy water and rinse them well. Rinse the beets with water without scrubbing, and don't peel them: scrubbing can remove the good bacteria they need to ferment. Cut away any damaged or moldy parts. Cut them into cubes.
Tip: Use raw beets, never cooked: cooking strips the bacteria on the skin, and they don't ferment the same way. This is a house rule.
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Dissolve the salt in the water
Weigh 1,000 g of water and 25 g of salt: that's a 2.5% brine. The salt is worked out on the water, not on the beets. Use canning salt, non-iodized, and stir until it dissolves. Filtered or spring water is best: tap water usually contains chlorine. Never use distilled water.
Tip: The 2.5% is a house rule, within the 2 to 10% of tested brines. Never go below 2%.
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Pack the beets and cover them with brine
Put the cubes in the jar as soon as you cut them, and no more than 24 hours later. Pour the brine over them. There should be at least 3 cm (about 1¼ inches) of brine above the beets; set the weight on top so they don't float. With no weight, a zip-top freezer bag filled with brine and sealed does the same: it fits the mouth of the jar and, if it leaks, does not dilute the salt.
Tip: Plan on about 900 g (2 pounds) of beets for a 2-liter jar: about 1 pound and 2 cups of brine per quart of jar.
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Close it and keep it somewhere cool
Close the jar and keep it at 60–70 °F. Never above 77 °F: in the heat it can spoil.
Close it the way you prefer
- Airlock lid
- The lid keeps air out and the airlock lets the gas escape: you don't need to touch it.
- Regular lid
- Close it, and every time you check on it, loosen it for a moment to let the gas out. Close it again right away.
Tip: The jar has to let the gas escape. And no metal containers: they react with the acid.
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Check the pH on day 7
The brine darkens, turns cloudy and starts to bubble: it's fermenting. No source gives a day count for beet kvass; the pH decides. On day 7, check it: it must have dropped to 4.6 or below. If it hasn't, throw it out. Once it reads 4.2 or below and you like the taste, salty and sour, it's ready.
Tip: The 4.2 is a house rule. Without a pH meter, wait at least 7 days before tasting it; that's a house rule too.
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Strain it and keep it in the fridge
Strain the kvass into clean bottles or jars, close them and keep them in the fridge. Left out, it would keep fermenting until it turned too sour and was no longer fit to drink.
No sign-up. We guide you step by step, from the scale to the fridge.
Variations
The same method, a different flavor. Once you have this one down, try one of these.
What you'll see
Beet kvass, also called fermented beet juice, is a brine you drink. At home, it's made with chunks of raw beet in a glass jar, covered with brine. Beets aren't acidic (pH 5.3–6.6), so everything depends on fermentation bringing the pH down to 4.6 or below, as with any vegetable. There's no official guidance on beet kvass: this recipe follows the guidance for vegetables in brine.
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How to tell it's going well
- Never less than 2% salt by weight of water. Reducing the salt in a vegetable ferment is unsafe.
- Keep the beets under the brine, with at least 3 cm (1¼ inches) above them. Anything poking out may spoil.
- pH 4.6 or below within a week. If it hasn't gotten there, throw it out: above 4.6, botulism spores can germinate. We recommend waiting for 4.2 before the fridge (house rule).
- At 60–70 °F, never above 77 °F.
- Fuzz or green, blue, brown or black spots are mold. Throw out the whole batch; it can't be scooped out.
- A white, gray or pink film is usually kahm yeast. Skim it off: if it grows too much, it lowers the acidity.
- A putrid smell: throw it out. The ferment has failed.
- In glass, with a way for the gas to escape. No metal.
- Once fermented, into the fridge. Left out, it keeps fermenting.
Where every number comes from
Every number in this recipe comes from a food safety guide. We keep a copy of each source and quote its exact words.
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1
Also known as fermented beet juice
“It is known as beet kvass, beet sourdough, fermented beet juice, pickled borscht, and pickled beet juice”
Foods (MDPI; Jakubczyk et al.), via PubMed Central · Phenolic Compounds and Antioxidant Properties of Fermented Beetroot Juices Enriched with Different Additives (2024) · read on October 25, 2026
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2
At home, chunks of beet go in a glass jar, covered with brine
“the raw material is cut into smaller pieces and placed in a glass jar that has been previously boiled, over which a salt solution, known as brine, is poured”
Foods (MDPI; Jakubczyk et al.), via PubMed Central · Phenolic Compounds and Antioxidant Properties of Fermented Beetroot Juices Enriched with Different Additives (2024) · read on October 25, 2026
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3
Chunks go in brine; shredded vegetables get dry salt
“Liquid brines are usually used for fermenting chunks, whereas salt is directly mixed with shredded or minced foods like sauerkraut.”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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4
10 g of salt per liter of water makes 1%
“1% solution = 10 g / L liquid”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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5
Tested recipes use 2 to 10% salt
“Tested recipes will fall between 2% and 10% brine concentrations.”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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6
Reducing the salt in fermented vegetables is unsafe
“It is unsafe to reduce salt in lactofermented vegetables.”
UC Master Food Preservers, Inyo-Mono · Brine Math Made Easy · read on October 20, 2026
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7
Beets have a pH of 5.3–6.6
“Beets 5.30 - 6.60”
U.S. FDA, CFSAN (copy hosted by RiverStone Health, Yellowstone County public health department) · Approximate pH of Foods and Food Products (April 2007) · read on October 25, 2026
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8
About 1 pound of vegetables and 2 cups of brine per quart jar
“Plan on using about 1 pound of vegetables per 1-quart jar and about 2 cups of brine.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
Show the remaining 36 claims
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9
Non-iodized salt
“Be sure to use non-iodized salt.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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10
Everything washed in hot soapy water and rinsed well
“Wash all surfaces and containers that will be used with hot sudsy water and rinse well before use.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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11
Anything poking out of the brine may spoil
“Fermenting vegetables may float to the surface and poke up out of the brine where they may spoil.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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12
A weight on top keeps them under
“Placing a weight (such as a jar or brine-filled bag) on top to keep them submerged is a good idea.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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13
The lid keeps air out and the airlock lets gas escape
“A lid prevents oxygen from entering the jar. However, it is important to vent the jar with a one-way valve to release the gases that form during fermentation.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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14
Without an airlock, loosen the lid now and then
“If a one-way valve is not used, the gases will need to be released manually by loosening the lid occasionally.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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15
At 60–70 °F it's slower, but turns out better
“A slower ferment at 60° to 70° F will yield better results than one fermented at higher temps.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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16
Left out of the fridge, it keeps fermenting until it's no longer fit to drink
“if left out at room temperature they will continue fermenting, becoming very sour and ripening beyond palatability and safety.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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17
Vegetable brines run 2 to 10%
“Vegetables are placed into containers and covered with a brine containing salt between 2 to 10% (or higher), depending on the vegetable.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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18
Only canning or pickling salt
“Only pickling or canning salts should be used.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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19
Vegetables washed, anything damaged or moldy thrown out
“Wash ingredients to remove soil and contamination, discard damaged, mouldy vegetables.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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20
Start the ferment as soon as you can, within 24 hours of cutting
“Once the vegetables are prepared the fermentation process should be initiated as soon as possible, and within a maximum of 24 hours.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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21
At least 3 cm of brine over the vegetables
“There should be at least 3 cm or more of liquid brine between the fermented vegetables and the top of the brine.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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22
No metal containers
“Metal containers are not suitable due to their reactivity with acid.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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23
The container must let gas escape
“During the fermentation, containers should allow gas to vent to avoid containers exploding.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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24
Above 77 °F it can spoil
“fermentation at temperatures higher than 25°C may result in spoilage.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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25
The brine turns cloudy as it ferments
“The brine becomes cloudy as the fermentation proceeds (week 1), then clears (week 4).”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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26
It must reach pH 4.6 or below
“Ensure effective fermentation and end pH of ≤4.6 is achieved.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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27
Above 4.6, botulism spores can germinate
“C. botulinum spores may germinate in fermented foods when pH rises above 4.6 during spoilage.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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28
If it doesn't reach 4.6 within a week, throw it out
“If pH has not dropped to 4.6 within one week consider this a failed fermentation and discard product.”
BC Centre for Disease Control, Environmental Health Services · Safety of Fermented Foods, Section 3.1: Fermented Vegetables (August 2024, updated December 2024) · read on October 25, 2026
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29
Salt is best weighed
“It is best to weigh salt for accuracy.”
University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
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30
Filtered or spring water is best
“Filtered water or spring water are preferred.”
University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
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31
Tap water usually contains chlorine
“Tap water usually contains chlorine, chloramines and fluoride that must be removed before culturing.”
University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
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32
Never distilled water
“Do not use distilled water.”
University of Illinois Extension · Fermentation handout (2020) · read on October 20, 2026
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33
Don't scrub, so the good bacteria stay on
“Do not scrub the produce, as you may remove the good bacteria needed for fermentation.”
University of Minnesota Extension · Preserving food at home: Fermentation (reviewed 2026) · read on October 25, 2026
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34
Best left unpeeled
“Avoid peeling the produce.”
University of Minnesota Extension · Preserving food at home: Fermentation (reviewed 2026) · read on October 25, 2026
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35
Open the lid only briefly
“The lid should only be opened briefly to limit oxygen from entering the container.”
University of Minnesota Extension · Preserving food at home: Fermentation (reviewed 2026) · read on October 25, 2026
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36
If there's mold, throw out the whole batch
“If you confirm mold growth on any part of a ferment, it should be immediately discarded.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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37
Mold is usually green, blue, brown or black
“Mold is typically green, blue, brown, or black in color.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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38
A white, gray or pink film may form
“White, grey, or pink films may form on the surface of fermenting fruits or vegetables.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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39
That film is usually kahm yeast
“This film is typically yeast, often referred to by home fermenters as Kahm yeast.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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40
Too much yeast lowers the acidity
“Excessive yeast growth can lead to off flavors or textures and reduce acidity.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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41
A putrid smell means the ferment failed
“A putrid smell indicates a failed fermentation.”
UC Davis, Department of Food Science and Technology · Common issues with fermented fruits and vegetables (v1.0, 15-mar-2022) · read on October 20, 2026
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42
Mold can't be scooped out
“The mold cannot be scooped out, as the roots will still be in your food and could make you sick.”
Ask Extension (Clackamas County Extension, Oregon State University) · Pickle/olive brine surface mold spots #889210 · read on October 20, 2026
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43
The bag holds brine: if it leaks, the salt is not diluted
“It is recommended that the brine solution be stored in plastic bags to ensure that the fermentation brine is not diluted should the bag leak or break.”
Virginia Cooperative Extension (Virginia Tech) · Vegetable fermentation (FST-328, reviewed 2025) · read on October 26, 2026
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44
The bag, well sealed
“Be sure to seal the plastic bag.”
National Center for Home Food Preservation (USDA, University of Georgia) · Suitable Containers, Covers, and Weights for Fermenting Food · read on October 26, 2026
