How to Activate a Kombucha Scoby



Our kombucha scobys are sold in a dehydrated state, which preserves the yeast and bacteria present in the culture while greatly reducing the chance of spoilage. We value the safety of our customers! Our kombucha scobys can be activated for use through the following rehydration process.

**Please note, we strongly recommend using white distilled vinegar when activating the culture and in the first batch. Please do not use rice vinegar or apple cider vinegar as they will lower the chances of your culture activating properly.



When viewing this video, please note that any vinegar used in the rehydration process should not be raw. Raw vinegar contains its own bacteria and may compromise the kombucha culture. We recommend using white distilled vinegar in the rehydration solution. Apple cider vinegar, rice vinegar, wine vinegar, or flavored vinegars can give less-than-optimal results.

Also please note that it is common for a new culture (baby) to NOT form in the rehydration batch, or even in the first couple of batches. You can successfully use the original culture to make additional batches of kombucha.

Prepare the Rehydration Solution


Equipment. Click here for more information on choosing the best brewing container, cover system, utensils and more.


  • One quart-size glass jar
  • A plastic or wood stirring utensil (never use metal in contact with a kombucha scoby!)
  • A breathable cover for the jar such as a tight-weave towel, paper towel, or paper coffee filter 
  • A rubber band to secure the cover to the jar


Ingredients. Click here for more information on choosing the best tea, sugar, and water source for making kombucha.



A note about hygiene. When working with kombucha, it is important not to introduce competing bacteria to the process. Be sure to wash and rinse your hands well prior to working with the tea mixture or the scoby. Also be sure to thoroughly clean and rinse the container and all utensils that will come in contact with the scoby. Beware soap and food residue the dishwasher may have missed. When in doubt, give everything an extra rinse. The brewing vessel can be cleaned with regular soap and hot water (rinse several times very well) or with vinegar. Never use bleach on any item that will come in contact with the kombucha.


Activating the Scoby


  1. Place hot water and sugar together in a jar. Mix until the sugar dissolves. The water should be hot enough to steep the tea but does not have to be boiling.   
  2. Place the tea in the sugar water and allow the tea to steep. Allow the mixture to cool to room temperature. You can remove the tea bag after the first 10 to 15 minutes or leave it longer for a stronger tea, but be sure to remove the tea before adding the dehydrated scoby. If using loose tea, make sure no flakes remain in the brewing solution. 
  3. Place the dehydrated kombucha scoby and vinegar in the jar of fresh sugared tea.
  4. Cover the jar to keep the fruit flies out but allow the mixture to breathe. A tight-weave towel or paper coffee filter secured by a thick rubber band works best for this. Do not use an air-tight lid!


Choose a safe spot. An ideal culturing spot should be relatively warm but not excessively so. Temperatures between 70° and 80°F are ideal. An ideal spot for fermenting kombucha should be out of direct sunlight. Indirect light or darkness is neither favorable nor problematic. Be sure the spot has reasonably good airflow as access to oxygen benefits the fermentation process. In addition, be sure the kombucha is not fermenting near a garbage or compost bin, bread made with commercial yeast, or any other cultured foods such as kefir, yogurt, sourdough, sauerkraut, etc. Cross-contamination by stray yeasts and bacteria can be problematic for the kombucha scoby.


Do not disturb. It is important to allow the kombucha to ferment undisturbed. Moving the jar or otherwise disturbing the contents will not ruin the batch but does make it more difficult to observe the most common signs the process is proceeding normally.


Signs the Rehydration Process is Complete


Allow the scoby to rehydrate for 30 days. 


A new scoby may or may not form on the surface of the liquid during the rehydration process. While development of a new scoby does indicate the rehydration process is complete, lack of a new scoby development does not indicate the process failed (see below). A new scoby will start out as a cloudy haze or film developing on the surface of the liquid. If left undisturbed, the haze will become less opaque and more white in color and will thicken over time. If the original scoby is floating in the liquid, a newly developing scoby may attach to the original scoby making it more difficult to identify whether a new scoby has developed.


Please note, development of a new scoby is not required for successful rehydration. If 30 days pass and a new baby scoby does not develop on the surface of the liquid, use the following criteria to determine whether rehydration has been successful:


  • If the scoby has thickened it indicates rehydration is proceeding normally. (It may thicken only slightly.)
  • Presence of brown stringy yeast particles or brown globs of yeast either floating or sticking to the scoby is a sign rehydration is proceeding normally and that active yeast and bacteria are present. Please note: while extra yeast particles are encouraging, lack of floating yeast particles is not a sign the process failed.
  • The scoby has developed an extra layer of substance on the top. This could be a piggyback scoby and happens when a newly developing scoby attaches itself to the original culture.
  • If the kombucha mixture is becoming more acidic, this indicates the process is proceeding normally. To test acidity you can either taste a bit of the mixture using a straw or use a pH meter or pH strip. (pH testing strips are available on our site or at most drugstores.) A pH level between 2.5 and 4.0 indicates the scoby has rehydrated properly.


If 30 days have passed and the signs above are present, it is likely the process has been completed successfully and the rehydrated scoby can be used to make a batch of kombucha. You may drink, bottle, or discard the kombucha from the rehydration. (We recommend using vinegar again in the first batch after rehydration.) Click here to view our comprehensive instructions and how-to video for making kombucha.


Signs of Problems During Rehydration


While problems during rehydration are relatively uncommon, it is important to keep an eye out for these few signs that the process isn’t proceeding normally.


30 days pass with no signs of proper rehydration (see above). Click here for additional troubleshooting information. In a small number of cases, live cultures fail for unknown reasons. After reviewing the troubleshooting link, contact Customer Support for additional information to determine whether the culture is inactive and whether a replacement is needed.


Mold. If you are using appropriate varieties of water, tea, and sugar and adding the acidic component (starter tea or vinegar), the acidic nature of the brew makes it very uncommon for mold to develop. In fact, the most common cause of mold is forgetting an ingredient or using improper ingredient ratios that alter the acidic level of the brew. However unlikely, mold can and does occasionally develop and can generally be seen by the formation of white, green, orange, red, or black spots on the scoby or the surface of the liquid. If mold does develop, immediately toss the entire batch including the scoby. Do not try to salvage a moldy batch or a moldy scoby. Doing so may be dangerous to your health. Contact Customer Support for additional assistance.


Pests. The kombucha mixture is very attractive to ants and fruit flies which is why we recommend using a tight-weave cover and securing the cover with a tight rubber band to keep the invaders out. If you find worms (maggots) have infested your batch, this is a sign that fruit flies or house flies have invaded and laid their eggs. If this happens, immediately toss the entire batch including the scoby. Do not try to salvage an infested batch or an infested scoby. Doing so may be dangerous to your health. Contact Customer Support for further assistance.


Next Steps


Once your kombucha scoby has finished rehydrating it is time to use it to make your first batch of kombucha tea. You may drink, bottle, or discard the kombucha from the rehydration. (We recommend using vinegar again in the first batch after rehydration.) Click here to view our comprehensive instructions and how-to video for making kombucha.

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