Alcohol-free kombucha – is it possible?

You are probably aware that, as in every fermented beverage, there is alcohol in kombucha.
Its level is determined by the amount of bacteria and yeast in the beverage, as well as by some processes during fermentation.
Most commonly, levels are 0.25-1% vol.
For comparison, beer levels are 4-6% and wine’s – 12-14%. The common thing about the fermentation of the three beverages is the yeast.
In that case, why the kombucha does not reach higher alcohol levels, such as wine?
The answer is that besides yeast, the drink also contains acetic and lactic acid bacteria, one of which is specific and is present only in the kombucha – Gluconacetobacter kombuchae.
They are actively involved in the fermentation process by reducing the alcohol levels.
Here’s how it happens:
The yeasts process the sugar into alcohol and CO₂ (carbonation), and the bacteria feed on the alcohol and convert it into organic acids.
This is how you get a sweet-sour, naturally carbonated drink called kombucha!
Knowing this, we can also answer if it is possible to make an absolutely non-alcoholic kombucha. The answer is – not in a natural way, because alcohol is an integral part of the fermentation process.
But we can regulate (increase or decrease) its quantity.
However, if yeast or bacteria have a striking predominance, then there is a danger that the process will not go right.
More yeast produces more alcohol, which from food can become a threat to bacteria.
On the other hand, as bacteria need alcohol to eat, the low content of yeast means low content of alcohol as well and this will cause negative effect, which will lead to an inactive kombucha drink.
Next I will give you some tips on how to reduce levels of alcohol, without impairing the manufacturing process of kombucha – the goal is to limit the population of yeast to reasonable proportions.
- By lowing the temperature – the yeast develops at a temperature of about 23 degrees, highly active they become at about 26-27 degrees. Reduce the temperature in the container to about 20-21 degrees and this will slow the growth of yeast and hence alcohol levels.
- By filtration of the starter fluid – during maturation, yeast concentrates mainly at the bottom of the container and is less attached to the sponge. If you use a filtered starter fluid, you will reduce the levels of active yeast in the new drink. You can use a strainer by adding gauze for even finer filtration. Or take a starter from very close to the sponge/SCOBY.
- Less sugar – yeasts feed on sugar. Less sugar will result in a weaker, inactive colony of bacteria.
- Clean SCOBY – Part of yeast are stored in the sponge as visible as brown deposits on culture. Wash them well with cold water before putting it on for the next maturing of kombucha.
- Bacteria increase – you can do this by putting a larger sponge in the new brewing. Wash it well with cold water beforehand. Combine with reducing the temperature of the container to about 21-22 degrees. You can get a thicker sponge by allowing your culture to grow into a container with larger bottle neck.
Good luck with the kombucha “for kids”, and in one of the following articles I will give you some tips on how to make a kombucha beer.