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Kombucha

Tea consumption is common all over the world and it has had a significant cultural impact. Not only tea, but also a tea-based beverage called kombucha is of great interest. Kombucha is a functional drink made from sweetened tea fermented with a symbiotic culture of bacteria and yeast (SCOBY)

Types of tea

The leaves of Camellia sinensis vary depending on the degree of oxidation, which results in six basic types of tea: non-oxidised green tea, slightly oxidised white and yellow tea, partially oxidised oolong tea and fully oxidised dark and black tea. Tea is famous for its beneficial properties, which can help prevent the occurrence of various diseases such as cancer, diabetes, arthritis, cardiovascular disease, stroke and obesity. These benefits are attributed to the bioactive compounds contained in tea leaves, such as catechins, amino acids, organic acids, vitamins, enzymes and minerals.

Making kombucha

Kombucha is made from sweetened tea fermented with a symbiotic culture of bacteria and yeast (SCOBY). This aerobic fermentation mainly involves acetic acid bacteria, lactic acid bacteria and yeast. Kombucha has a slightly sweet and sour taste with a hint of saturation, resembling cider or sparkling wine, yet maintaining a negligible alcohol content.

The tea and sugar proportions, as well as the fermentation time and temperature used in Kombucha production, may vary depending on the area or consumer taste. Generally, to produce kombucha, a tea base is prepared and then some sugar is added, which will serve as a substrate for the bacteria and yeast for fermenting the tea. The microbiome contributing to the fermentation of kombucha is diversified and differs from fermentation to fermentation, but consists mainly of acetic bacteria and yeast, but also the presence of small amounts of lactic acid bacteria. These micro-organisms are believed to be potential probiotics and therefore contribute to health benefits.

Kombucha under scientific investigation

Kombucha is a fermented beverage that has recently attracted consumer attention and is widely considered a functional beverage. There has been rapid growth in the market in recent years, with more and more research on the drink. It is believed that fermented tea was first used in East Asia for its medicinal properties in 220 BC. However, it originated in north-eastern China, where it was adopted for its detoxifying qualities and stimulating properties.

Chemical analysis of kombucha revealed the presence of various organic acids such as: acetic, gluconic, glucuronic, citric, L-lactic, malic, tartaric, malonic, malonic, oxalic, succinic, pyruvic, usnic; as well as sugars such as sucrose, glucose and fructose; vitamins B1, B2, B6, B12 and C; 14 amino acids, biogenic amines, purines, pigments, lipids, proteins, some hydrolytic enzymes, ethanol, antibiotic-active substance, carbon dioxide, phenol, as well as some tea polyphenols, minerals, anions, DSLs, and other products of yeast and bacterial metabolism.

The intake of a fermented drink such as kombucha, also helps improve digestion and fight against harmful bacterial growth. Many studies have shown that this drink is not only a probiotic but also acts as a symbiotic, a combination of prebiotics and probiotics. Probiotics, according to the FAO/WHO, are “live microorganisms that, when provided in adequate amounts, have beneficial effects on the health of the host”. A prebiotic selectively promotes the growth and activity of a consortium of beneficial microorganisms present in the human gut.

Kombucha is a ‘magic’ tea with valuable health-promoting properties. It is a beverage produced as a result of the fermentation process of sweetened tea. Kombucha has been the subject of numerous scientific studies. These studies have proven that it is a completely safe product. In addition, it has been shown to have beneficial effects on human health.

 

  1. Almeida, T. S. D., Araújo, M. E. M., Rodríguez, L. G., Júlio, A., Mendes, B. G., Santos, R. M. B. D., & Simões, J. A. M. (2019). Influence of preparation procedures on the phenolic content, antioxidant and antidiabetic activities of green and black teas. Brazilian Journal of Pharmaceutical Sciences
  2. Andreson, M., Kazantseva, J., Kuldjärv, R., Malv, E., Vaikma, H., Kaleda, A., … & Vilu, R. (2022). Characterisation of chemical, microbial and sensory profiles of commercial kombuchas. International Journal of Food Microbiology
  3. Antolak, H., Piechota, D., & Kucharska, A. (2021). Kombucha tea—A double power of bioactive compounds from tea and a symbiotic culture of bacteria and yeasts (SCOBY). Antioxidants
  4. Chakravorty, S., Bhattacharya, S., Chatzinotas, A., Chakraborty, W., Bhattacharya, D., & Gachhui, R. (2016). Kombucha tea fermentation: Microbial and biochemical dynamics. International journal of food microbiology

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