Characteristics and biochemical composition of kombucha – fermented tea

Abstract

Introduction. Kombucha is a fermented tea beverage produced by using a symbiotic culture of bacteria and yeast, so-called SCOBY. The tea fungus comes from the regions of East Asia, and was brought to Europe from eastern Siberia. Kombucha is also known under other names, modst commonly as Chinese or Japanese mushroom. In process of fermentation of kombucha many metabolites are produced which are responsible for its pro-health properties. Objective. The aim of the study is to present a review of the current state of knowledge concerning the chemical reactions, and chemical and microbiological composition of kombucha. Brief description of the state of knowledge. The components found in the beverage are organic acids, mainly acetic acid, vitamins and mineral components, polyphenols, flavonoids, enzymes and fats, as well as sugars. In microbiological terms, it is a mixture of acetic acid and lactic acid bacteria and yeast. Acetobacter xylinum bacteria and Schizosaccharomyces pombe yeast are most often present in the beverage. Yeast cells consume most of the fructose in the process of glycolysis, producing ethanol and carbon dioxide. In turn, ethanol is converted into acetic acid due to acetic acid bacteria present in the beverage. Kombucha shows antimicrobial, antioxidant, anti-diabetic properties, reducing the level of cholesterol, supporting the immune system, and also stimulating liver detoxification. Conclusion. Differences in chemical and microbiological composition of kombucha depend mainly on the variety and type of tea, the amount of sugar used, temperature, pH, and fermentation time.

Chemical Profile and Antioxidant Activity of the Kombucha Beverage Derived from White, Green, Black and Red Tea

“…Unhealthy lifestyle, intense physical exercising, stress, and environmental pollution are factors that influence the excessive synthesis of reactive oxygen species. The disturbance in homeostasis caused by free radicals leads to the formation of oxidative stress and damage to the structures of the human organism [1][2][3][4]. Illnesses that can be caused by free radical disorders include atherosclerosis, neurodegenerative diseases, such as Parkinson's or Alzheimer's disease, or even obesity.…”

Evaluation of Fluoride and Selected Chemical Parameters in Kombucha Derived from White, Green, Black and Red Tea

“…3.00 ± 0.00* 3 2.61 ± 0.03* 1, 5 10.0 ± 0.00* 1,3,5,8 703.92 ± 0.02* 1,5,8,11 14 2.75 ± 0.50* 1,2 2.49 ± 0.04* 1 8.75 ± 0.00* 1,2,3 914.74 ± 0.31* 1,9,12 Black tea kombucha -BK Tea 0.00 ± 0.00 5.34 ± 0.03* 1,5,6,7,10 11.0 ± 0.00* 5 2.35 ± 0.01 7 3.25 ± 0.50* 2,6,8,11 2.62 ± 0.03* 2,4,6,11 9.50 ± 0.00* 2,4,6 703.91 ± 0.03* 2,8,11 14 2.00 ± 0.00* 4,5,9,12 2.53 ± 0.03* 4,5,9, 12 7.50 ± 0.00* 5 908.30 ± 0.36* 4,5,9,12 White tea kombucha -WK Tea 0.00 ± 0.00 6.53 ± 0.05* 4,8,9 10.75 ± 0.00 2.11 ± 0.01* 8,9 7…”

“…3.50 ± 0.50* 2,5 2.53 ± 0.05* 7,9 10.13 ± 0.00* 2 704.81 ± 0.17* 2,5,7,9 14 3.00 ± 0.00* 3,6 2.37 ± 0.05* 6,7,8 9.50 ± 0.00 913.22 ± 0.43* 6,7,8,12 Red tea kombucha -RK Tea 0.00 ± 0.00 5.58 ± 0.07* 4,11,12 10.75 ± 0.00* 11 2.04 ± 0.03* 11,12 7…”

“…Still, black tea and white sugar (sucrose) are regarded as the traditional and at the same time the best ingredients, making for the optimal composition of the finished beverage and its health benefits. The taste of kombucha is described as sour and fruity, slightly carbonated, becoming similar to the taste of wine vinegar after a few days' storage [2]. Studies demonstrated the antimicrobial, antioxidant and antidiabetic properties of kombucha, lowering cholesterol and boosting the immune system, as well as stimulating liver detoxification [4].…”

“…The tea is left at room temperature to ferment for 7-21 days. Kombucha can be made with different types of tea, including green tea and fermented (oxidised) varieties, like red, black and yellow tea [1][2][3]. Still, black tea and white sugar (sucrose) are regarded as the traditional and at the same time the best ingredients, making for the optimal composition of the finished beverage and its health benefits.…”