Its health care functions include: cleaning the stomach, preventing constipation and hemorrhoids; Help digestion; Can be used for preventing and treating cardiovascular diseases, such as hypertension, hyperlipidemia, arteriosclerosis and diabetes; Avoid all kinds of stones; Help the body eliminate toxins in time, prevent cancer and enhance the body's immunity. It can be said that it is a good health drink.
Although Kombucha has a long history in China, its scientific research started late. In 18+0, Fang, a famous microbiologist in China, published the article "What is a sea treasure" in the fifth issue of the Yellow Sea magazine, which is the first scientific paper on black tea fungus in China. In this paper, it is considered that the main microbial species of black tea fungus are acetic acid bacteria and yeast, and it is pointed out that there is more than one kind of acetic acid bacteria in black tea fungus, but it is mainly membrane vinegar bacteria. From the late 1970s to the early 1980s, kombucha beverage was very popular in China. A large number of articles introduced the efficacy and production methods of kombucha. From the early to the middle of the 20th century, some doctors and scholars have reported the role and function of black tea fungus in treating various diseases.
Since the mid-20th century, there have been reports on the microbial composition, interaction, fermentation conditions, composition and action mechanism of black tea fungus.
1 strain type
Species of black tea fungus and their relationships. Acetobacter and yeast are the main strains used for the fermentation culture of Kombucha, and some Kombucha strains contain a small amount of lactic acid bacteria [mainly Lactobacillus Blazei].
Up to now, Acetobacter, Acetobacter xylinum, Acetobacter xylinum, Gluconobacter and Acetobacter ketoacidogenes have been isolated from various black tea fungi. Acetobacter weakly oxidized, Gluconobacter liquefied, Acetobacter aceti and Acetobacter pasteurella, among which Acetobacter xylinum is the most important.
Yeast includes Saccharomyces cerevisiae, inconspicuous yeast, Ludwig II, Schizosaccharomyces pombe, Candida tropicalis, candidate yeast, Dbaly II, Brettanyomyces, Kloeckera, Zygosaccharomyces bailii, etc. The strains that ferment black tea fungus are composed of the above-mentioned one or more acetic acid bacteria and the above-mentioned one or more yeasts, and some of them are lactic acid bacteria.
Different strains have different kinds and quantities of metabolites in their liquid. Yeast and Acetobacter are mutually beneficial in black tea fungus.
Study on fermentation conditions of 2
Mi-Ae-Choi (1994) and others studied the effects of different temperatures (5 ~ 45℃) and carbon sources (sucrose, glucose, fructose and corn syrup) on the pH and total acid of Kombucha. The results showed that the optimum temperature for acid production by fermentation was 30℃, and the organic acids produced by sucrose and fructose, glucose and corn syrup were similar. The metabolic rate of fructose is much faster than that of glucose, while the metabolic rate of fructose and glucose is faster than that of sucrose. Jürgen Reiss( 1993) used different carbon sources (sucrose, fructose, lactose and glucose) with different concentrations to treat the metabolites (ethanol and lactic acid) of Kombucha (a strain composed of Acetobacter xylinum, Acetobacter pseudoxylophilus, Glucobacterium, Schizosaccharomyces pombe, Rhodotorula, etc.) at the fermentation temperature of 20 ~ 22℃, and sucrose could increase the yield. Martin Sievers et al. (1995) studied the fermentation of two strains of Kombucha (including different yeast species). They cultured Kombucha at room temperature (20 ~ 22℃) for 60 days and tested its fermentation process. Results Different yeasts have different utilization rates of glucose and fructose and different metabolic processes. Yeast plays a decisive role in the utilization of sugar, and different yeasts use sugar in different ways. Matin Sievers and others also pointed out that the Acetobacter xylinum they used can metabolize lactic acid, so they did not detect lactic acid like Jürgen Reiss.
Analysis of three components of black tea fungus
Some scholars have analyzed the components contained in the liquid of black tea fungus. Different data have different results because of different strains, culture conditions, analysis methods and analysis emphasis.
German Gü nther W. Frank (1991) thinks that black tea fungus contains glucuronic acid, gluconic acid, acetic acid, alcohol, lactic acid, amino acids, protein, folic acid, lichenic acid, Vc and various B vitamins [14]. Liu et al. (1995) analyzed two species of black tea fungus from Taiwan Province province by HPLC. The results showed that the black tea fungus contained glycerol, acetic acid and ethanol.
Michael R. Roussin of the United States (1996) reported that 9 samples of/kloc-0 from the United States and other parts of the world were analyzed by HPLC/MS/PDAD. Results glucuronic acid, which was almost recognized as a functional factor before, was not found, and the contents of various vitamins were few, but many were detected.
They detected more than 40 chemicals from 19 species of black tea fungus. How these substances work after entering the human body needs further scientific research. Biljanabauer-Petrovska (1998) analyzed the minerals and soluble vitamins in black tea fungus by atomic absorption chromatography and thin layer chromatography. The results show that the contents of zinc, copper, iron, manganese, nickel and cobalt beneficial to human body are higher than those of unfermented tea, while the contents of lead and chromium harmful to human body are very few and far lower than those of tea. This shows that microorganisms can increase beneficial elements and reduce harmful elements.