Preparation

• Sterilize the glass jar that will be used as a fermenter by submerging it in boiling water for 10 minutes.
• Accurately weigh the sugar and set aside in a small bowl.
• Heat the water until it reaches 95ºC, ensuring that the paddle we'll use for stirring is inside while heating.
• Remove the water from the heat and add the tea. Stir gently to ensure a good mix.
• Let the tea steep for 8 minutes with the lid on to maintain the temperature.
• Add the sugar to the water with the tea and stir until it is completely dissolved.
• Remove the tea bags or strain the tea if loose herbs were used.
• Let the tea cool down to room temperature, around 20ºC. We can accelerate the cooling with a cold water bath. Cover to prevent water from entering the container.
• Once the tea is at room temperature, add the starter culture (an unpasteurized homemade kombucha) into the fermenter and then pour in the tea, being careful not to fill it to the brim.
• Cover the fermenter jar with a paper towel and secure the towel with a rubber band to allow for ventilation.
• Let the fermenter rest in a dark place at room temperature, ideally between 20ºC and 25ºC, ensuring that the temperature does not exceed 30ºC.
• Allow to ferment for about 10-14 days. According to Fermentsbcn's recommendation, it can be left for 20-30 days for a more acidic flavor.
• The longer the fermentation time, the more acidic and less sweet the result will be.
• The shorter the fermentation time, the sweeter and less acidic the result will be.
• From the tenth day onwards, we can taste the kombucha with a sterilized spoon to check the flavor.
• Once the taste is to our satisfaction, proceed to the carbonation phase.
• Prepare a funnel and pre-sterilized bottles. Boil the remaining sugar until it reaches a boil. Use this opportunity to also sterilize a tablespoon.
• According to the lady from Fermentsbcn, additional sugar should not be used for carbonation. We need to keep testing it, and when it reaches the desired acidity but is still slightly sweet, we bottle it and allow some carbonation with the residual sugar, without adding more.
• Let the syrup cool to room temperature before proceeding.
• Carefully remove the yeast disk (Scoby) or any yeast that has formed on the surface of the fermenter.
• Pour the syrup into the fermenter and let it rest for a while so that the sediment settles at the bottom.
• Fill the bottles with a funnel, leaving two fingers of empty space at the neck of the bottle for proper carbonation.
• Let the bottles sit for 3 days at room temperature to complete the carbonation.
• Then, place all the bottles in the refrigerator to slow down the fermentation process.
• Consume after 15-20 days from bottling. It's advisable to keep a bit of the fermented tea for the new batch to accelerate and ensure the process in future preparations. If you only want to make kombucha occasionally, an unpasteurized craft kombucha as a starter culture works effectively.