Is Kombucha naturally carbonated?


The tea drink Kombucha is offered as an "elixir of life" and a remedy for almost all diseases. However, the advertised effects have not been scientifically proven.

The tea is said to improve bowel function, activate the immune system and stimulate the metabolism as well as purify the blood. Kombucha is recommended for numerous diseases: for example gout, rheumatism, blemished skin and also as protection against cancer and cardiovascular complaints. Such disease-related statements are not only scientifically not proven, they are also prohibited. Current systematic overview studies have only found case reports on side effects (see below), but no indications of positive effects.

What is Kombucha?

Kombucha is made with the so-called tea or kombucha mushroom, a gelatinous mass that contains a mixture of different bacteria and yeasts. This is why the Kombucha culture is also known as SCOBY ("symbiotic culture of bacteria and yeast"). This ferments sugared tea into a must-like, carbonated drink. During fermentation, alcohol and acetic acid, lactic acid and gluconic acid are produced from the added sugar. This makes kombucha taste sour and contains between 0.7 and 1.3 percent alcohol.

Kombucha was originally part of Asian folk medicine. With us, the tea mushroom is mainly available in health food stores and health food stores, but is also often passed on from hand to hand. Kombucha can be found as a ready-to-drink drink in the food and beverage trade.

What is the finished drink made of?

Kombucha is made from sweetened herbal tea, green tea or black tea. Depending on the preparation and fermentation time, it sometimes contains as much sugar as lemonade (up to 10 percent). Fermentation also produces carbon dioxide, various acids, especially acetic acid, lactic acid and gluconic acid, and alcohol (0.1 to 2%). Homemade kombucha contains living microorganisms.

How healthy is kombucha?

When properly made, Kombucha is a harmless soft drink, whereby the content of alcohol, caffeine and possibly sugar must be taken into account. Its health effects are comparable to those of other fermented foods, such as sour milk products, whose microorganisms can have a positive effect on the intestinal flora.

The extent of this effect is unknown with Kombucha. Scientifically proven are only slightly laxative and weak antibacterial effects, which are due to the content of acetic and lactic acid.

Industrially produced kombucha is pasteurized for shelf life reasons. This kills the microorganisms in the fermented drink - they become ineffective. Those who hope for additional effects should only buy products with living cultures.

What should you watch out for during production?

When making kombucha yourself, you need to pay special attention to hygiene. Kombucha contaminated with foreign germs, especially mold (toxins), can cause problems for sensitive people, especially people with an immune deficiency.

Please note when preparing:

  • Hands, fermentation vessel (no ceramics!) And equipment must be thoroughly cleaned with hot water before each new batch.
  • About 100 milliliters of the finished drink are added to the starter liquid.
  • To prevent insect infestation, you have to cover the fermentation vessel with a cloth and secure it with a preserving rubber.
  • If mold develops or changes in color and odor, you must discard the entire culture.

Make sure to use a suitable container (e.g. glass) when making it at home. For example, people who had regularly drunk kombucha for six months, which was set in a ceramic vessel with a lead-containing glaze, suffered lead poisoning. The acid from the fermented drink can dissolve the lead from the glaze.

Possible harmful effects

There have been isolated reports of people who have had allergic reactions, nausea, muscle inflammation, dangerous over-acidification of the blood (in one case with fatal consequences), or liver disease after consuming kombucha.

In most cases it was kombucha made at home, and in some cases the source is not recorded. The respective homemade kombucha approach may have been contaminated with harmful microorganisms.

However, these case reports cannot prove that the cause of the serious health problems was actually kombucha.


In terms of food law, Kombucha is a drink of its own with a low alcohol content (0.1-2%). In any case, it is used for refreshment, but not as a remedy. The proportion of sugar, alcohol and caffeine varies greatly. Some commercially available products are useful as low-calorie thirst quenchers. However, the high sales price of up to 4 euros and more per liter is offset by a questionable benefit.