Kombucha

Kombucha appears to be a fungus but it isn’t one at all. We call it this, tough, for the sake of convenience, kombucha is a tough, slippery, waxy mass which forms several layers. Those layers consist of transparent, very tough tissue with a series of brown spots, mainly at the bottom. Looking through a microscope you can see that the brown spots are concentrations of yeast cells.

The smooth, white side of the fungus is the top side, out of which the fungus grows. The bottom side is rough and brown. The fungus first grows in width, then in thickness. It takes the form of the receptacle in which it lies. A round demijohn gives a round fungus, the larger the recipient the larger the fungus.

The kombucha fungus can be a smooth, transparent, waxy round plate one time, a white or grey uneven mass the next. Sometimes a leathery thick layer with scarred tissue. Or a convex slice with bubbles on top and slimy threads below, giving it a jellyfish appearance.

Actually, kombucha is a variable community of all sorts of yeast and bacteria, a complex of tiny microscopically creatures, a factory with different useful and wholesome substances.

As a living creature the fungus is subordinate to external factors, such as nutrition and oxygen, temperature etc. It can vary in composition depending on the influence of the cultivation applied by its origin and hygiene.

The fungus does not always react to its environment in the same way, so not have the same appearance all the time, just like two apples from the same tree are never alike.

• Fermentation receptacle: It is best that the kombucha fungus has no contact with metal, plastic or other synthetic material. When in longer contact with these receptacle unwanted chemical reactions occur and toxic metal salts are formed. The safest, most trouble-free manner is to use a glass receptacle.
• Clear water: The quality of the water plays a big part in the preparation of kombucha. Soft, clear drinking water is an absolute necessity, free from chlorine and fluorine (added to drinking water in some countries). The most sufficient method would be the use of tap water combined with a water softener.
• Tea: Only non-perfumed black or green tea is suitable, they contain essential nutrients the kombucha needs.
• Sweetener: Sugars serve as the energy source for the kombucha.
• Warmth: The right temperature is crucial, below 18°C is harmful for the fermentation. The optimal temperature lies around 25 to 30°C. With the use of a warming plate you can easily create a constant temperature for the fermentation process.
• Oxygen: Oxygen is vital, so never hermetically seal your demijohn. Close the jar with a fine-meshed cloth that is sufficiently held in place by an elastic band. No dirt or vinegar flies can be allowed near the fungus.
• Hygiene: First of all: wash your hands thoroughly with non-perfumed soap. Keep the necessary equipment spotless. Always rinse with clear (boiling) water. Do not use disinfectant. Keep your workplace clean and free of unnecessary objects. Remove flower pots from the area as the germs can cause infection.
• Rest: The growth of a new fungus begins with a thin film at the surface of the liquid. This film will not grow if the surface is shaken. Later, when the fungus has grown, movement can cause the fungus to sink, with the result that the sunken fungus has to start all over again.