After the first fermentation turns your sweet tea into a fermented kombucha tea full of health benefits, the second fermentation imparts flavor and carbonation. Learn about the benefits, flavors, and duration of kombucha’s second fermentation below.
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What Is the Difference Between the First and Second Fermentation?
The first fermentation combines black tea, sugar, starter tea, and a SCOBY (symbiotic culture of bacteria and yeast). These ingredients start the fermentation process of your kombucha. During this stage, the SCOBY infuses your brew with probiotics, microorganisms, organic acids, and carbon dioxide. This primary fermentation produces kombucha that is both sweet and sour but not fizzy.
The first fermentation takes between seven and thirty days. The exact amount of time you first ferment depends on your tea and sugar ratio, your brewing temperature, and the age and quality of your SCOBY. The longer you let your batch of kombucha ferment, the less sweet it becomes.
The second fermentation gives kombucha carbonation and flavor. To start the second fermentation, transfer your kombucha to glass bottles and add fruit or spices. Be sure to leave about 1 inch of headspace so your brew has space to breathe and carbonate. Use airtight bottles for the second ferment so the carbon dioxide bubbles can multiply and make your brew fizz.
During the second fermentation, let the bottles sit at room temperature and burp them daily. Flip-top bottles make it easy to open the cap and let the pressure escape so it doesn’t get too fizzy. Then seal the bottles back up and let them continue to ferment. Taste your kombucha each day during the second fermentation. When you like the taste, put it in the fridge to stop fermentation.
How Long Is the Second Kombucha Fermentation?
The second fermentation process lasts between two and five days. You can 2nd ferment your kombucha in a big batch or in smaller bottles to make multiple flavors. The duration of the 2nd ferment depends on the room temperature, which flavorings you use, and how sweet you like your kombucha to taste. The longer you let it ferment, the tangier it will become.
What Are the Benefits of a Second Fermentation?
By adding sweeteners in the second fermentation, the tea becomes slightly sweeter. Add any sweetener, including honey, fruit, white sugar, brown sugar, or maple syrup.
The secondary fermentation also:
- Allows you to experiment with flavors—get creative with flavor combinations you enjoy or imitate store-bought varieties.
- Produces a build-up of carbon dioxide—if you like bubbly kombucha, you’ll want to 2nd ferment!
Is a Second Fermentation Necessary When Brewing Kombucha?
No, the second fermentation is not necessary. The first fermentation fills your kombucha with beneficial enzymes, acids, and probiotics. It is safe to drink after the first fermentation. If you don’t enjoy fizzy beverages, you may even prefer your kombucha after the first fermentation since it is less carbonated. If you enjoy fizzy or flavored kombucha, you’ll want to do a second fermentation.
What Can You Add to Kombucha for the Second Fermentation?
You can add just about any fruit, herb, or spice to kombucha for the second fermentation. The choice is yours! Add flavors you enjoy, and don’t be afraid to experiment. You can follow specific kombucha recipes or use what you have on hand.
Try simple additions like:
- Cinnamon—start with 1/4 teaspoon per cup of kombucha
- Dried fruit—begin with a small handful, but keep in mind that dried fruit usually has a higher sugar content
- Fruit juice—start with about 1/4 cup of fruit juice for 1 cup of kombucha
- Fresh fruit or frozen fruit—strawberries, mango, apple, peaches, raspberries, blackberries
- Fruit puree
- Fresh ginger—about a 1-inch slice, chopped fine
- Vanilla—1/4 teaspoon per 1 cup of kombucha
Or, try classic flavor combinations like:
- Blueberries and lemon
- Cherries and almond extract
- Ginger and cinnamon
- Ginger and lemon
- Hibiscus flowers
- Mint and lime
- Pineapple and coconut extract
- Pumpkin spice
- Strawberries and basil
- Turmeric and cinnamon
As always, when brewing your own kombucha, be sure to check for mold or ‘off smells’ before consuming.