Can you make vinegar from kombucha?
Yes. Kombucha vinegar is simply kombucha that has been allowed to ferment far longer than you would for a drink. During a normal batch, yeast in the culture turns sugar into alcohol, and acetic acid bacteria turn that alcohol into acetic acid, the acid that makes vinegar sour. Left alone for an extended time, the balance shifts toward acid and the sweetness fades, leaving a sharp, tangy liquid.
Many home fermenters report that this takes somewhere around two to three months, though timing depends on temperature, how much sugar you started with, and how strong your culture is. Treat any number as a rough guide and rely on taste and smell.
One important caution up front: homemade kombucha vinegar has an acidity nobody has measured, so do not use it in place of commercial vinegar labeled 5% acidity when you are canning or pickling for shelf storage. Tested canning recipes assume a known acidity. See the National Center for Home Food Preservation for tested recipes.
What you need
- A clean glass jar with a wide mouth (a one-gallon jar is common for a full batch)
- Water, plain white sugar, and tea made from true tea leaves (black or green; herbal teas are generally not recommended as the main tea)
- A kombucha SCOBY plus some unflavored, mature kombucha as starter liquid
- A tightly woven cloth or paper coffee filter and a rubber band for the cover
- A fine strainer and clean bottles for storage
A common home ratio for kombucha is around a cup of sugar and several tea bags per gallon, with a cup or two of starter liquid. Some brewers add slightly more sugar for a vinegar batch to keep the culture fed during the long ferment. If you are new to brewing, follow a trusted kombucha recipe for the first batch and adjust from there.
Step 1: Brew sweet tea and cool it
Boil some of the water, stir in the sugar until it dissolves, and steep the tea for around ten minutes. Remove the tea, add the rest of the water as cool water, and let the mixture come to room temperature before it touches the culture. Hot tea can harm or kill the SCOBY; a commonly cited guideline is to keep the tea below about 90 F (32 C) when you add it, and cooler is safer.
Step 2: Add the SCOBY and starter
Pour the cooled tea into your clean jar, add the starter liquid, and gently slide the SCOBY in. The starter liquid keeps the brew acidic from the start, which helps discourage unwanted microbes. If you do not yet have a SCOBY, you can sometimes grow one from raw, unflavored store-bought kombucha, though that takes weeks.
Step 3: Cover and ferment longer
Cover the jar with a tightly woven cloth or a coffee filter, held in place with a rubber band. Loose cheesecloth can let fruit flies through, and flies are a common contaminant. Set the jar somewhere warm, out of direct sunlight, with good airflow and away from fruit bowls.
Then leave it alone. A new layer of SCOBY will form on the surface, and the liquid will gradually lose sweetness and gain sharpness. Because the jar is open to air, the oxygen helps the acetic acid bacteria do their work.
How to tell when it is ready
- Taste a small spoonful from beneath the surface every week or two once the batch smells distinctly vinegary.
- It is ready when it tastes sharply sour with little to no sweetness left.
- The smell should be like vinegar, not rotten, cheesy or moldy.
You can also use pH strips or a meter, but remember that a reading alone does not make homemade vinegar equivalent to a tested, standardized product.
Straining, bottling and storing
Remove the SCOBY (set it aside in some of the liquid if you plan to brew again), strain the vinegar through a fine mesh or coffee filter, and pour it into clean glass bottles. Use a cap that is not bare reactive metal, since strong acid can corrode some metal lids. Store it in a cool, dark place. Some people keep it in the refrigerator for extra caution, which is reasonable if you are unsure about the batch.
A new thin film or small floating bits may reappear in storage. Smooth, jelly-like film is typically more cellulose; fuzzy growth is not.
Using kombucha vinegar (and where not to)
Good uses include salad dressings, marinades and splashes into soups or sauces for tang. It tastes best diluted into other flavors rather than taken straight. Because the acidity is uncertain, avoid it for water-bath canning, pickles meant for pantry storage, or any recipe where safety depends on a specific acidity. For those, use store-bought vinegar labeled 5% acidity, as in our easy pickle recipes for canning.
If you are looking for what to do with the leftover culture, see what to do with a SCOBY after first fermentation.
Troubleshooting: mold, film and smells
- Fuzzy, dry or colored spots (green, black, blue, white and powdery) on the surface: this is likely mold. Discard the whole batch, including the SCOBY.
- Brown strands hanging below the SCOBY: usually yeast and generally normal.
- Smooth, beige film on top: typically a new SCOBY layer.
- Fruit flies or larvae: discard the batch and use a tighter cover next time.
- Smells like rotten food, nail polish remover, or something unpleasant rather than vinegar: when in doubt, throw it out.
Frequently asked questions
What temperature kills a SCOBY?
There is no single exact number, but heat is the main risk. Pouring hot tea over a SCOBY can damage it, so let tea cool to room temperature first. Many sources suggest keeping brewing temperatures in the range of roughly 70 to 80 F (21 to 27 C).
What is vinegar?
Vinegar is a sour liquid made by fermentation: sugars become alcohol, then bacteria convert the alcohol to acetic acid. Commercial vinegars are standardized to a stated acidity, which kombucha vinegar made at home is not.
What is a basic kombucha tea recipe?
Yes. A normal kombucha batch uses the same sweet tea, SCOBY and starter described above, just fermented for a shorter time, often one to a few weeks, until it is pleasantly tart. Making ordinary kombucha first is a good way to learn how your culture behaves before attempting a long vinegar ferment.