Today marked my first experience with kombucha and what an interesting experience it was. Below is a picture of kombucha in the making with the one undergoing the primary fermentation on the left and the one undergoing second fermentation on the right.
It’s interesting to see how after 2.5 hours of adding more tea into the starter culture, the starting of a microbial cellulose pellicle, a physical result of the fermentation process, can be observed.
Kombucha is a fizzy drink created by a primary aerobic fermentation process followed by a secondary anaerobic process.
Primary stage
The aerobic fermentation process starts off with a symbiotic culture of bacteria and yeasts (SCOBY) in a tea substrate from a previous batch of kombucha. Then by adding more brewed tea with sugar, one introduces more quantity of tea for the current culture of bacteria and yeast to act on.
It is important to cool the tea down quickly as the lukewarm zone is the prime time for contamination, which is to be avoided.
Fun fact!
Nata de coco is produced through a similar fermentation process as well and is actually fermented coconut water and not coconut jelly/ compressed coconut flesh.
Secondary stage
The second fermentation increases the amount of sugar being introduced into the fermented kombucha for flavouring and carbonation purposes. The sugar can be introduced in the form of a sugar lozenge, normal sugar or even fruit juice to create different flavours. At this stage, it is important to choose the right bottle for this process as the carbonation process might cause too much build up pressure in the bottle because of the amount of CO2 released, which could cause the bottle to break.
In general though, the most important idea to take away from this seminar is in how you want to apply this fermentation process. Shaking the bottle during the secondary fermentation process can be done to increase homogeneity of fermentation but could introduce the taste of yeast more greatly, which is not necessarily a taste appreciated by every person. Since tastes are perceived differently by everyone, there is not one specific desired taste to achieve and experimentation in different ratios of tea to fermentation ingredients should be encouraged to discover the type of kombucha that one would enjoy most.