New video series from "Scientific American" and Spektrum der Wissenschaft provide you with scientific services. In this episode, let’s take a look at effervescent fermented tea that has become a health boom.

View the German version of this article on Spektrum der Wissenschaft.

You may have seen it in supermarkets, health care stores and even restaurants: Kombucha. This effervescent fermented tea is sometimes called the "elixirs" by those who tout its supposed health benefits. But what is it and how is it made? Where do these health benefits come from?

The key to creating kombucha is fermentation.

It is the process of using microorganisms—especially yeast and bacteria—to convert carbohydrates into alcohol or organic acids.

People have always used fermentation to preserve fish, meat and vegetables. Since the millennium, some programs originally used in Asia have become global culinary trends.

The drink is made by the symbiotic culture of bacteria and yeast or the action of SCOBY. It produces beverages through fermentation.

Usually, this is done by letting SCOBY loosen in a fermentation vessel containing soaked sweetened tea.

Once SCOBY is added to the tea, it forms a loose floating mat to get as much contact with the nutrient medium as possible. The mixture was exposed to the air, and a complex chemical dance began.

Acetic acid bacteria, such as Gluconacetobacter and Acetobacter, and lactic acid bacteria, such as Lactobacillus, work with several yeast flora.

Together, they inhibit the growth of potentially contaminating bacteria. In about 7 to 10 days, they convert sugar and tea into a mildly carbonated and slightly acidic beverage composed of a variety of acids (including amino acids, vitamins and enzymes).

Many studies have shown that Kombucha has antibacterial, anti-inflammatory, anti-oxidant and even anti-cancer properties, at least in petri dishes. 

There are various rumors about how kombucha should be beneficial to people:

It is said to help prevent high blood pressure.

Drinking it should make you feel more energetic.

Some people believe that it can strengthen the immune system, lower bad cholesterol and reduce the risk of heart attack.

But this has yet to be scientifically proven. It is worthwhile to further study the impact on human health under controlled research. Some studies have even reported cases of toxicity related to the consumption of Kombucha.

This is why Kombucha is not classified as a drug: it is a refreshing drink that promotes health.

To ensure that Kombucha is safe to eat, the brewing process requires industry standards.

In the United States, Kombucha Brewers International has developed best practice guidelines to ensure the safety and quality of these products.

In Europe, such organizations do not yet exist.

In any case, properly produced Kombucha is a harmless and refreshing drink.

But be aware: some kombucha beers may contain 0.1% to 2% alcohol.

Unless you are looking for the buzz of kombucha, be sure to avoid gulping. This is your scientific service.

Michael Tabb, Jeffery DelViscio and Andrea Gawrylewski

Michael Tabb, Jeffery DelViscio and Andrea Gawrylewski

Michael Tabb, Jeffery DelViscio and Andrea Gawrylewski

Spektrum and Scientific American employees

Spektrum and Scientific American employees

Spektrum and Scientific American employees

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