How do I make my homemade kombucha as fizzy as the store bought brands?
I pondered this question for years. Some of my batches bubbled over but others were relatively flat. Then I learned of a process called secondary fermentation (or bottle fermentation) that’s used when making sparkling wines. It is easily adapted for use with kombucha and yields a reliably carbonated brew.
A breathable cover is essential for brewing kombucha, but it allows the carbonation to escape. The solution is to culture the sweetened tea, but only allow it to partially ferment. The brew is then bottled and fermented for the remaining time. The natural yeasts become more active in the airless environment and the carbonation they produce is trapped. The result is a wonderfully fizzy kombucha tea.
Here’s what to do:
Brew the kombucha and store it to ferment as called for in the 5-Step Kombucha Recipe (go through step 3). Only allow the fermentation to continue until the new s.c.o.b.y. (also called a mushroom) becomes opaque, in 3-5 days, depending on room temperature. The kombucha should taste sweet, but should be entirely cultured. The fully formed new “baby” s.c.o.b.y. is a sign that the brew is ready to be bottled.
Remove the mother and baby s.c.o.b.y. from the brew. Use a wooden spoon to mix in the sediment in the bottom of the jar. The sediment contains yeasts that are important for carbonation.
Use bottles with tightly fitting lids. Fill the bottles full – leaving only ¼-inch of head space. This creates a nearly airless environment. Place a layer of wax paper under the lid. The wax paper acts as a gasket to help trap the carbonation inside the bottle.
After the kombucha has been bottled the secondary fermentation process is already underway! Store the bottles in a warm (about 72 degree F) place. After 2-3 days test one bottle by unscrewing the cap. If there is a noticeable release of carbon as the lid is opened then move the bottles to the refrigerator. This may take up to 4 days depending on the room temperature.
Use caution and patience when opening bottle fermented kombucha. During warm weather (over 75 degrees F) the bottles are more likely to bubble over when quickly opened. This is especially true if the brew is allowed to warm to room temperature before opening, just like our favorite store brands!
Six Steps to Carbonated Kombucha
- Brew kombucha according to the 5-Step Kombucha Recipe (through step 3).
- Only allow the brew to ferment until an opaque “baby” s.c.o.b.y. forms.
- Remove mother and baby s.c.o.b.y. from the brew. Stir the sediment in the bottom until it is evenly distributed.
- Bottle the kombucha in jars with tightly fitting lids. Use a sheet of wax paper under the lid.
- Store in a warm place until noticeable carbon releases when the bottle is opened, in 2-4 days.
- Move into the refrigerator. Strain before serving.