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Kombucha tea fermentation: Microbial and biochemical dynamics

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  • Helmholtz Centre for Environmental Research - UFZ & Leipzig University
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... and Brettanomyces spp. are the core drivers of kombucha fermentation [4,5], although lactic acid bacteria (LAB) such as Lactobacillus and Leuconostoc have also been systematically isolated from the beverage [6,7]. Traditionally, culture-based methods were relied upon for characterisation of the microbial composition of kombucha [4,8], however the emergence of culture-independent techniques such as metabarcoding has allowed for a more in-depth analysis of kombucha microflora and their metabolic activities and interactions [6]. ...
... Based on similar observations, Muhialdin et al. [26] recommended a fermentation period of 12 days for optimal antioxidant activity and phenolic content. The microbial composition of kombucha can also be influenced by fermentation, with an in-depth study by Chakravorty et al. [7] revealing significant changes in microbial community and diversity over 21 days. Candida initially dominated yeast in the liquid portion of the kombucha; however, a shift in dominance to Lachancea spp. on day 7 of the fermentation was observed. ...
... Kombucha fermentation consists of metabolically active bacteria and yeast, which thrive in two mutually non-exclusive compartments: the fermented liquid and the pellicle or biofilm floating on it [7]. The microbial composition of kombucha varies greatly from one batch to another and is dependent on the origin, substrate and fermentation conditions ( Table 1). ...
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Kombucha is a carbonated, slightly acidic beverage traditionally produced by the fermentation of sweetened tea by a symbiotic culture of bacteria and yeast (SCOBY). The microbial community of kombucha is a complex one, whose dynamics are still not fully understood; however, the emergence of culture-independent techniques has allowed a more comprehensive insight into kombucha microbiota. In recent times, advancements have been made towards the optimisation of the fermentation process, including the use of alternative substrates, defined starter cultures and the modification of fermentation parameters, with the aim of producing an innovative beverage that is improved in terms of its physiochemical, sensory and bioactive properties. The global kombucha market is rapidly increasing, with the rising popularity of the tea attributed in part to its purported health benefits, despite the lack of research in human subjects to substantiate such claims. Accordingly, the incidence of kombucha home-brewing has increased, meaning there is a requirement for individuals to recognise the potential hazards associated with fermentation and the relevant preventative measures to be undertaken to ensure the safe preparation of kombucha. The aim of this review is to provide an update regarding the current knowledge of kombucha production, microbiology, safety and marketing.
... Initial pH of 2.77 (TK), 2.80 (PFK) and 2.19 (UCFK) was found to have reduced over time for all beverages. This decrease is mainly attributed to the production of organic acids from fermentation, but the addition of acidic fruits can also contribute to a reduction in the pH (Chakravorty et al., 2016;Leonarski et al., 2021). Both pitanga and umbu-cajá pulps influenced the kombucha pH over time; however, umbu-cajá led to the reduction of pH, whereas pitanga led to the increase of it. ...
... A similar behavior was observed by Abuduaibifu and Tamer (2019) in kombucha produced with red and black goji berry stored under refrigeration. Soluble solids are related to the content of sugars in the medium that reduce over the fermentation time, since microorganisms use these compounds as energetic substrates (Chakravorty et al., 2016). This reduction in sugars (glucose and fructose) was identified in all evaluated beverages (Fig. 1). ...
... This variation in flavored beverages may be associated with the difference in fructose concentrations in pitanga and umbu-cajá fruits Vizzotto et al., 2011). Still, the smaller fluctuations in the fructose levels when compared to the glucose levels in the different storage times of flavored beverages might be associated with the primary use of glucose in the metabolic pathway by microorganisms, mainly yeasts (Chakravorty et al, 2016Jayabalan et al., 2014;Leonarski et al., 2021). ...
Article
The present study aimed to evaluate the impact of the addition of pitanga (Eugenia uniflora L.) and umbu-cajá (Spondia tuberosa) fruits on the physicochemical parameters, volatiles, phenolics (profile and bioaccessibility) and antioxidant capacity of kombucha. All beverages TK (traditional kombucha), PFK (pitanga-flavored kombucha) and UCFK (umbu-cajá-flavored kombucha) showed throughout the 7-day evaluation process a reduction in pH, an increase in acidity, and a reduction in the content of soluble solids and sugars (glucose and fructose) that characterize the fermentation process. Higher values and lower sugar losses were found in the flavored kombuchas, showing that the pre-existing levels of glucose and fructose in fruits contributed to sweeter beverages. Acetic, butyric, citric, succinic, and malic acids were identified in all kombuchas, except for the malic acid in PFK. Terpenes were the main volatile compounds described in beverages, which was found to have favored the sensorial profile of PFK and UCFK, as they contributed to the increase and/or appearance of new terpenoids, such as curzerene and β-caryophyllene. In contrast, TK presented acetic acid as its major component. High antioxidant activity was observed for fruit flavored kombuchas, and among the identified phenolics, epigallocatechin gallate was the most predominant component in all beverages (above 63%). The most bioaccessible phenolics in all kombuchas were caftaric acid (22.38%–29.98%), catechin (17.61%–23.48%) and hesperidin (22.43%–28.47%). After a simulated gastrointestinal digestion, the phenolic contents in all kombuchas reduced, having an influence on the significant drop of the antioxidant capacity. Findings demonstrated that pitanga and umbu-cajá contribute to diversify and improve the chemical and bioactive characteristics of the kombucha, revealing a sweeter beverage, with a tendency to fruity aromas.
... Kombucha, also known as Manchurian mushroom, Haipao, or tea fungus, has been used in the fermentation of drinks dating back to several thousand years (Jarrell et al., 2000;Teoh et al., 2004;Četojević-Simin et al., 2012) and is purported to have detoxifying and energizing properties when imbibed (Teoh et al., 2004;Marsh et al., 2014). The Kombucha "tea fungus", or pellicle, can be considered a "core" consortium of bacteria and yeasts, with its exact composition determined by its geographic and climatic conditions of cultivation (Chakravorty et al., 2016). It is thought that the additional "local" bacteria and yeasts have some effect on the growth behavior of the overall community (Jayabalan et al., 2014) and that the microbial community composition can vary with fermentation time. ...
... It has been widely documented that the brewing of Kombucha tea for more than 3 days can lead to the "core" consortium producing a BC pellicle on the surface. Similar production is observed when Kombucha is used to inoculate standardized microbiological media such as Hestrin and Schramm (commonly known as H&S) or Yamanaka broth (Schramm and Hestrin 1954;Jarrell et al., 2000;Yamanaka and Sugiyama 2000;Chakravorty et al., 2016). ...
... Marsh et al. (2014) used Kombucha pellicles as inoculants from different geographical locations and analyzed the microbial communities present after 3 and 10 days of fermentation in black tea using metagenomic DNA extraction and highthroughput sequencing techniques and found that in all cases, Komagataeibacter was the dominant bacterial genus, with the highest diversity of microbial strains found in the cellulosic pellicles. Similar data were identified by Chakravorty et al. (2016) where Kombucha pellicles and liquids were assessed at 3-, 7-, 14-, and 21-day fermentation. Komagataeibacter was the dominant bacterial genus in both the liquid and pellicle at all time-points with microbial diversity declining throughout the study. ...
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The textile industry is in crisis and under pressure to minimize the environmental impact on its practices. Bacterial cellulose (BC), a naturally occurring form of cellulose, displays properties superior to those of its cotton plant counterpart, such as enhanced purity, crystallinity, tensile strength, and water retention and is thus suitable for an array of textile applications. It is synthesized from a variety of microorganisms but is produced in most abundance by Komagataeibacter xylinus. K. xylinus is available as a type strain culture and exists in the microbial consortium commonly known as Kombucha. Whilst existing literature studies have described the effectiveness of both K. xylinus isolates and Kombucha in the production of BC, this study investigated the change in microbial communities across several generations of sub-culturing and the impact of these communities on BC yield. Using Kombucha and the single isolate strain K. xylinus as inocula in Hestrin and Schramm liquid growth media, BC pellicles were propagated. The resulting pellicles and residual liquid media were used to further inoculate fresh liquid media, and this process was repeated over three generations. For each generation, the thickness of the pellicles and their appearance under SEM were recorded. 16S rRNA sequencing was conducted on both pellicles and liquid media samples to assess changes in communities. The results indicated that the genus Komagataeibacter was the most abundant species in all samples. Cultures seeded with Kombucha yielded thicker cellulose pellicles than those seeded with K. xylinus, but all the pellicles had similar nanofibrillar structures, with a mix of liquid and pellicle inocula producing the best yield of BC after three generations of sub-culturing. Therefore, Kombucha starter cultures produce BC pellicles which are more reproducible across generations than those created from pure isolates of K. xylinus and could provide a reproducible sustainable model for generating textile materials.
... Acetobacter aceti ( Balentineet al., 1997 ;Chen & Liu, 2000 ;Greenwalt et al., 2000 ;Liuet al., 1996 ;Teoh et al., 2004 ;Vina, 2014 ) Brettanomyces sp. ( Chakravorty, Bhattacharya, Chatzinotas, Chakraborty, Bhattacharya, & Gachhui, 2016 ;Chen et al., 2000 ;Coton et al., 2017 ;Liu et al., 1996 ;Villarreal-Soto, Beaufort, Bouajila, Souchard, & Taillandier, 2018 ) Acetobacter pasteurianus Chen et al., 2000 ;Greenwalt et al., 2000 ;Liu et al., 1996 ;Teoh et al., 2004 ;Vina, 2014 ) Brettanomyces bruxellensis ( Chen et al., 2000 ;Liu et al., 1996 ;Villarreal-Soto et al., 2018 ) Acetobacter xylinoides Liu et al., 1996 ;Teoh et al., 2004 ) Brettanomyces intermedius ( Heerrera et al., 1989 ) Acetobacter xylinum Chen et al., 2000 ;Greenwalt et al., 2000 ;Teoh et al., 2004 ;Watawana et al., 2015 ) Brettanomyces lambicus ( Mayser et al., 1995 ) Allobacullum sp. Martínez Leal et al., 2018 ) Candida sp. ( Chakravorty et al., 2016 ;Coton et al., 2017;Jankovj & Stojanovj, 1994 ;Liu et al., 1996 ;Mayser et al., 1995 ;Teoh et al., 2004 ) Bacterium gluconicum Liu et al., 1996 ;Teoh et al., 2004 ) Candida formata ( Heerrera et al., 1989 ) Bifdobacterium sp. ( Watawana et al., 2016 ) Kloeckera apiculata ( Mayser et al., 1995 ) Enterococcus sp. ...
... Martínez Leal et al., 2018 ) Candida sp. ( Chakravorty et al., 2016 ;Coton et al., 2017;Jankovj & Stojanovj, 1994 ;Liu et al., 1996 ;Mayser et al., 1995 ;Teoh et al., 2004 ) Bacterium gluconicum Liu et al., 1996 ;Teoh et al., 2004 ) Candida formata ( Heerrera et al., 1989 ) Bifdobacterium sp. ( Watawana et al., 2016 ) Kloeckera apiculata ( Mayser et al., 1995 ) Enterococcus sp. ...
... ( Martínez Leal et al., 2018 ) Kloeckera sp. ( Liu, Hsu, Lee, & Liao, 1996;Mayser et al., 1995 ;Teoh et al., 2004 ) Gluconobacter oxydans ( Vina, 2014 ;Watawana et al., 2015 ) Kluyveromyces sp. ( Chakravorty et al., 2016 ;Coton et ( Heerrera et al., 1989 ) Saccharomyces cerevisiae subsp. cerevisiae ( Goh et al., 2012b;Heerrera et al., 1989 ;Liu, Hsu, Lee, & Liao, 1996;Mayser et al., 1995 ;Teoh et al., 2004 ;Villarreal-Soto et al., 2018 ) Saccharomyces ludwigii ( Goh et al., 2012 ;Liu, Hsu, Lee, & Liao, 1996;Mayser et al., 1995 ;Teoh et al., 2004 ) Schizosaccharomyces pombe ( Chen et al., 2000 ;Goh et al., 2012 ;Liu, Hsu, Lee, & Liao, 1996;Mayser et al., 1995 ;Teoh et al., 2004 ;Villarreal-Soto et al., 2018 ) Torula ( Jankovj & Stojanovj, 1994 ) Torulaspora delbrueckii ( Heerrera et al., 1989 ) Torulopsis sp. ( Goh et al., 2012b;Mayser et al., 1995;Jankovj & Stojanovj, 1994 ;Liu et al., 1996 ;Teoh et al., 2004 ) Zygosaccharomyces ( Mayser et al., 1995 ) Zygosaccharomyces bailii ( Chen et al., 2000 ;Goh et al., 2012 ;Greenwalt et al., 2000 ;Liu et al., 1996;Mayser et al., 1995 ;Teoh et al., 2004 ;Watawana et al., 2015 ) Zygosaccharomyces kombuchaensis ( Heerrera et al., 1989;Vina, Linde, & Denin¸a, 2014 ) Zygosaccharomyces rouxii ( Heerrera et al., 1989;Villarreal-Soto et al., 2018 ) ...
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Fermentation is one of the oldest preservation techniques used by mankind with known actions of fermentation dating back to several millennia before the common era. From this came the fermentation of tea beverages which we commonly call kombucha. The origins of fermented teas, and ultimately the concept of kombucha, has a multitude of backstories and derivations stemming back several thousand years. Kombucha is made by fermenting sweetened black or green tea using a mixed fermenting culture of yeast and acetic acid bacteria. This review gives a holistic overview of the fermented tea beverage known as kombucha including an overview of the history of kombucha, an overview of the brewing and manufacturing of the beverage including different brewing techniques and ingredients, discussion of the biochemical and microbiological aspects of the fermentation process, the flavor and chemical profile of kombucha, as well as the impacts of kombucha on human health.
... These constituents, which are beneficial for health, have made Kombucha a popular healthy beverage. It's popularity has recently risen in the United States of America (Chakravorty et al., 2016), and it is predicted to reach 3.5-5 billion USD in the global market by 2025 (Kim & Adhikari, 2020). ...
... Peterson, 2010), and inoculum size (Sen & Swaminathan, 2004) are critical factors for optimal production of the main functional metabolites of Kombucha. The use of the proposed microbial community reconstruction method significantly increased the proportion of gluconic acids of Kombucha, which was higher in the present study compared to that in previous studies (Chakravorty et al., 2016;Conton et al., 2017). This method could provide a reference for the quality control of Kombucha. ...
... traditional Kombucha, and were also higher than those in previous reports (Chakravorty et al., 2016;Lin et al., 2015;Sknepnek et al., 2021;Suna, Ciftci, & Tamer, 2020;Wang et al., 2020;Wang, Gan, Tang, Wang, & Tan, 2010;Yildiz, Guldas, & Gurbuz, 2021). The Kombucha samples with a high proportion of gluconic acid achieved a high taste score, indicating that enhancing the proportion of gluconic acid could improve the taste quality of Kombucha. ...
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In this study, a synthetic microbial community (SMC) was used to enhance the proportion of gluconic acid in order to improve the taste quality of Kombucha. The sensory properties of gluconic acid were analyzed for the first time. The proportions of gluconic acid (r = 0.986, p < 0.05) and acetic acid (r = −0.986, p < 0.05) were significantly correlated with the taste score of Kombucha, which was confirmed by the analysis of the sensory properties of organic acid monomers. Starmerella davenportii with the highest yield of ethanol and Gluconacetobacter intermedius with the highest yield of acetic acid were screened and used for microbial community reconstruction to obtain Kombucha with the highest proportion of gluconic acid (74%). In addition, the sensory quality and concentrations of the main functional metabolites in Kombucha fermented by SMC were significantly increased compared with the traditional Kombucha. The microbial community reconstruction method effectively improved the taste quality of Kombucha.
... Kambucha tea as a functional beverage containing a combination of vitamins, metabolites, proteins, fiber, and other essential nutrients can play an effective role in reducing the incidence and even treatment of some diseases such as diabetes and cancer [5]. Kombucha tea is a fermented beverage native to Asia, which has become popular in other parts of the world because of therapeutic potentials like antioxidant, antimicrobial, immune-boosting, anti-cancer, hepatic detoxification, and anti-diabetic activities [6]. The merits of Kombucha tea can be due to the existence of probiotics, antibiotics, polyphenols, organic acids, amino acids, carbohydrates, water-soluble vitamins, ethanol, and various fermentation-derived micronutrients [7,8]. ...
... One hundred milligrams of KFE-PNPS was dissolved in 10 mL of PBS (pH: 7.4) and gently shaken. At specific times (6,12,24,48, and 72 h), 1 mL was removed from the solution and centrifuged at 9000 rpm for 5 min. The removed medium was replaced with an equal volume of fresh medium. ...
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The aim of this study was to load kombucha-fermented extract (KFE) on PLGA nanoparticles (KFE-PNPs) to increase bioavailability and to evaluate its anti-cancer effects. The KFE-PNPs (water1/oil/water2) were characterized using scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS) assays, followed was measured the encapsulation efficiency (%EE) and release of KFE by UV spectrophotometer. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) procedure was used for investigation of KFE-PNPs toxicity, and then, the pro-apoptotic capacity of KFE-PNPs was evaluated by acridine orange (AO) and propidium iodide (PI) staining, flow cytometry, and molecular analysis for P53 and TNF-α genes. The angiogenic effect of KFE-PNPs was evaluated using chick chorioallantoic membrane (CAM) and real-time PCR (VEGF gene expression) methods. The DLS results showed the formation of stable particles (zeta potential: − 26.27 mv) in nanometer dimensions (288.32 nm) with uniform dispersion index (PDI: 0.3). The %EE of KFE in PLGA-NPs was reported to be 71%. The selective toxicity effect of KFE-PNPs against A2780 (IC50 < 200 µg/mL) in comparison with HFF (IC50 > 500 µg/mL) cells was reported. The pro-apoptotic effects of KFE-PNPs were confirmed by increasing the number of apoptotic cells in the AO/PI staining, increasing the percentage of SubG1 phase cells in flow cytometry, and increasing the expression of apoptotic genes (P53 and TNF-α). Decreased expression of VEGF gene in qPCR procedure as well as decreased length and number of blood vessels and embryonic growth factors in CAM assay showed anti-angiogenic effects of KE-PNPs. According to the results, KFE-PNPs can be suggested for more research on cancer therapy.
... The SCOBY association, also known as "tea fungus", in the form of a cellulosic biofilm, transforms the sugar and tea components into bioactive compounds with probiotic effects. The main bacteria in "tea fungus" are AAB, mainly species from the genera Acetobacter (Acetobacter aceti, Acetobacter pasteurianus, Acetobacter nitrogenifigens), Gluconacetobacter (Gluconacetobacter sp A4, Gluconacetobacter sacchari, Gluconacetobacter oxydans), and Komagataeibacter (Komagataeibacter xylinus, Komagataeibacter kombuchae) [164]. AAB is part of the relatively stable bacterial community in kombucha and is responsible for the oxidation of ethanol which leads to the production of acetic acid. ...
... AAB is part of the relatively stable bacterial community in kombucha and is responsible for the oxidation of ethanol which leads to the production of acetic acid. Other secondary metabolites such as gluconic acid (from glucose), glucuronic acid (from glucose; detoxifying properties), and D-saccharic acid-1,4-lactone (from glucose; radical-scavenging; some Gluconacetobacter species) are also produced [164]. The main yeasts found in kombucha are Saccharomyces sp., Zygosaccharomyces kombuchaensis, Torulopsis sp., Pichia spp., Brettanomyces sp. ...
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Recent social, economic, and technological evolutions have impacted consumption habits. The new consumer is more rational, more connected and demanding with products, more concerned with the management of the family budget, with the health, origin, and sustainability of food. The food industry over the last few years has shown remarkable technological and scientific evolution, with an impact on the development and innovation of new products using non-thermal processing. Non-thermal processing technologies involve methods by which fruit juices receive microbiological inactivation and enzymatic denaturation with or without the direct application of low heat, thereby lessening the adverse effects on the nutritional, bioactive, and flavor compounds of the treated fruit juices, extending their shelf-life. The recognition of the nutritional and protective values of fruit juices and fermented fruit beverages is evident and is attributed to the presence of different bioactive compounds, protecting against chronic and metabolic diseases. Fermentation maintains the fruit's safety, nutrition, and shelf life and the development of new products. This review aims to summarize the chemical and sensory characteristics of fruit juices and fermented fruit drinks, the fermentation process, its benefits, and its effects.
... During Kombucha fermentation, the floating pellicle (tea fungus) rests on the liquid tea broth (Chakravorty et al., 2016). The tea fungus is usually recovered and utilised with a small amount of tea broth in the next fermentation. ...
... However, there are limited studies on the composition of Kombucha starter cultures and their metabolic characteristics. The main challenges in understanding Kombucha cultures are the diversity and complexity of the microbial communities involved (Chakravorty et al., 2016). Variations in culture composition may be due to climatic and geographic conditions (Mayser et al., 1995). ...
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The demand for Kombucha, a sparkling sugared tea beverage fermented by a symbiotic culture of acetic acid bacteria (AAB) and yeast is increasing worldwide. Despite the popularity of the beverage which is mainly due to its perceived health benefits and appealing sensory properties, the microbial composition of the products at the time of consumption is unknown. Such information is important to both manufacturers and consumers. Therefore, this study characterised the dominant AAB and yeast present in six commercial Kombucha samples sold in New Zealand which comprised of three domestic and three imported samples. Acetic acid bacteria and yeast were isolated from the Kombucha samples using glucose yeast extract peptone mannitol (GYPM) and yeast extract glucose chloramphenicol (YGC) media, respectively. Phenotypic and taxonomic identification of AAB and yeast were achieved by morphological and biochemical characterisation, followed by sequence analysis of ribosomal RNA genes (16S rRNA for AAB and 26S rRNA for yeast). Viable AAB and yeast were only found in domestically produced Kombucha samples and not in the imported products. The dominant AAB species were identified as Acetobacter musti and Gluconobacter potus. The yeast isolates belonged to Dekkera bruxelensis, Schizosaccharomyces pombes, Hanseniaspora valbyensis, Brettanomyces anamalus, Pichia kudriavzevii, Starmerella vitis and Saccharomyces cerevisiae. The yeast communities were more complex and variable than the AAB communities in the analysed Kombucha samples.
... The dominant bacterial species in the kombucha consortium belong to acetic acid bacteria (AAB), mainly to the Komagataeibacter genus (earlier named as Gluconacetobacter and before as Acetobacter (Chakravorty et al., 2016;Marsh et al., 2014;Yamada et al., 2012)), such as Komagataeibacter intermedius (Reva et al., 2015), Komagataeibacter xylinus (De Filippis et al., 2018;Reva et al., 2015), Komagataeibacter rhaeticus (Semjonovs et al., 2017), Komagataeibacter saccharivorans (De Filippis et al., 2018;Reva et al., 2015) and Komagataeibacter kombuchae (Reva et al., 2015). Also, species from the genera of lactic acid bacteria (LAB) such as Lactobacillus, Leuconostoc, and Bifidobacterium have been identified in kombucha (Villarreal-Soto et al., 2018). ...
... Our results showed that the amount of these acids was insignificant. Controversially, these concentrations vary in the literature from 2.3 g/L (Jayabalan et al., 2007) to 7.36 g/L (Chakravorty et al., 2016). Moreover, the metabolic pathways of gluconic and glucuronic acids showed that these acids could be metabolised to other chemical components, such as ascorbate, amino sugars, cofactors, and inositol ("KEGG COM-POUND C00191," n.d.). ...
Article
The kombucha market is a fast-growing segment in the functional beverage category. The selection of kombuchas on the market varies between the traditional and flavoured kombuchas. Our research aimed to characterise the chemical, microbial, and sensory profiles of the commercial kombuchas. We analysed 16 kombuchas from 6 producers. The dominant metabolites were acetate, lactate, and ethanol, the last of which might put some kombuchas into the alcoholic beverage section in some countries. The metagenomic analyses demonstrated that LAB dominates in green tea, and AAB in black tea kombuchas. The main bacterial species were Komagataeibacter rhaeticus and Lactobacillus ssp, and yeast species Dekkera anomala and Dekkera bruxellensis. The sweet and sour balance correlated with acid concentrations. The free sorting task showed that commercial kombuchas clustered into three main categories “fruity and artificial flavour”, herbal and tea notes”, and “classical notes”. Our research results showed the necessity of the definition of kombucha.
... In the case of l-glucuronic acid, the same authors observed a maximum concentration of 2.3 g/L, in black tea kombucha, on the 12th day of fermentation. Likewise, Chakravorty et al. (2016) observed an increase in acetic and gluconic acids concentration in green tea kombucha. The concentration of both acids increased with time and reached 16.57 and 7.36 g/L, respectively, after 21 days of fermentation. ...
... In the study conducted by Chakravorty et al. (2016) on black tea kombucha, ethanol concentration increased with time, reaching a maximum value of 0.028% on the 7th day of fermentation, followed by a decrease to about 0.0073% after 21 days of fermentation. This decrease in ethanol concentration was related to its use by acetic bacteria in the production of acetic acid. ...
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Kombucha has been gaining prominence around the world and becoming popular due to its good health benefits. This beverage is historically obtained by the tea fermentation of Camellia sinensis and by a biofilm of cellulose containing the symbiotic culture of bacteria and yeast (SCOBY). The other substrates added to the C. sinensis tea have also been reported to help kombucha production. The type as well as the amount of sugar substrate, which is the origin of SCOBY, in addition to time and temperature of fermentation influence the content of organic acids, vitamins, total phenolics, and alcoholic content of kombucha. The route involved in the metabolite biotransformation identified in kombucha so far and the microorganisms involved in the process need to be further studied. Some nutritional properties and benefits related to the beverage have already been reported. Antioxidant and antimicrobial activities and antidiabetic and anticarcinogenic effects are some of the beneficial effects attributed to kombucha. Nevertheless, scientific literature needs clinical studies to evaluate these benefits in human beings. The toxic effects associated with the consumption of kombucha are still unclear, but due to the possibility of adverse reactions occurring, its consumption is contraindicated in infants and pregnant women, children under 4-years-old, patients with kidney failure, and patients with HIV. The regulations in place for kombucha address a number of criteria, mainly for the pH and alcohol content, in order to guarantee the quality and safety of the beverage as well as to ensure transparency of information for consumers.
... Wheat, being one of the ancient crops used in bread making, has the specific elastic protein of gluten which is responsible for expansion of the dough and most of the time for bread's texture. The production specifications are mostly associated with the formation of gluten, which requires both the hydration of proteins in the flour and the application of energy through the process of kneading (Cauvain, 2003). Modern bread-making practices do not differ from the ancient techniques. ...
... In recent years, increasing consumer interest in functional uses, fermented juices are proposed as alternatives to traditional fermented dairy-based products with functional properties (Panda et al., 2017). Other fermented beverages, like non-dairy kefir and kombucha (fermented brewed tea) are examples of famous products comprising lactic acid bacteria and yeasts (Chakravorty et al., 2016). ...
... This symbiotic culture is also known as Kombucha and composed of 8-10 genera of acetobacteria, the most important of which is Komagateibacter, and of 15-30 yeast genera (Zygosaccharomyces, Candida, Kloeckera, etc.). The species composition of the symbiotic culture is detailed elsewhere (Chakravorty et al. 2016;Marsh et al. 2014). Since this producer is characterized as being highly adaptable and unpretentious to the ambient environment (Yurkevich and Kutyshenko 2002), it was decided to use the nutrient media unsterilized, which simplifies and cheapens the technological process (Kiziltas et al. 2015). ...
... The symbiotic culture is known to be a nonpathogenic producer; therefore, it is safe for the staff to work with it (Chakravorty et al. 2016;Marsh et al. 2014;Pillai et al. 2021). The subsequent purification of BC from cells and nutrient medium residues allows safe products to be obtained. ...
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The global abundance and availability of oat hulls make them a promising feedstock to produce a unique type of cellulose, the bacterial one. This is the first study examining how a chemical pretreatment method of oat hulls influences the yield and properties of bacterial cellulose (BC) in extended cultivation. Here we employed our own pretreatment methods that use dilute HNO3 and NaOH solutions in one and two stages, a total of four pretreatment methods. Further technological stages were performed in the same manner: pulps were enzymatically hydrolyzed with commercial enzymes CelloLux-A and BrewZyme BGX, and biosynthesis of BC was run using the Medusomyces gisevii Sa-12 symbiotic culture. A two-stage (HNO3 + NaOH) pretreatment of oat hulls was found to afford a biologically good medium and increase the BC yield 1.8−3.2-fold compared to the other pretreatments used. A pretreatment method of oat hulls determined the BC yield and degree of polymerization. However, a pretreatment method had no impact on the highest crystallinity index and allomorph Iα content of all the BC samples, which is explained by Medusomyces gisevii Sa-12 used. The crystallinity index and allomorph Iα content, as measured by X-ray diffractometry, are proposed for use as BC quality assessment criteria. Graphical abstract
... The pellicle on the surface of the aqueous phase in kombucha increases the access to oxygen for the microbes embedded in the cellulose matrix [20]. In general, Komagataeibacter (historically known under several names, including Gluconacetobacter and Acetobacter) species possess the ability to produce cellulose and is the dominant bacterial genus in kombucha [21][22][23][24]. ...
... K. rhaeticus (27.2%) and K. hansenii (18.8%) formed a total of 95.4% out of the identified species in Komagataeibacter genus ( Supplementary Fig. S3). Komagataeibacter are well-known producers of cellulose and can be present in kombucha [21,23]. Hence, the strong cellulose production observed by our kombucha culture must be attributed to these dominant Komagataeibacter species. ...
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Bacteria forming biofilms at oil-water interfaces have diverse metabolism, they use hydrocarbons as a carbon and energy source. Kombucha is a fermented drink obtained from a complex symbiotic culture of bacteria and yeast, where acetic acid bacteria present in kombucha use sugars as a carbon source to produce cellulosic biofilms. We hypothesize that Komagataeibacteraceae in kombucha can adsorb to and use hydrocarbons as the sole energy source to produce cellulosic biofilms. Hence we characterized a kombucha culture, studied bacterial adsorption and cellulosic biofilm formation of kombucha at the n-decane or mineral oil-kombucha suspension interface. The cellulosic biofilms were imaged using fluorescence microscopy and cryo-scanning electron microscopy, and their time-dependent rheology was measured. Komagataeibacter, the dominant bacterial genus in the kombucha culture, produced cellulosic biofilms with reduced cellulose biomass yield at the oil-kombucha suspension interfaces compared to at the air-kombucha suspension interface. The presence of biosurfactants in the supernatant secreted by the kombucha microbes led to a larger and faster decrease in the interfacial tension on both oil types, leading to the formation of stable and elastic biofilm membranes. The difference in interfacial tension reduction was insignificant already after 2 h of biofilm formation at the mineral oil-kombucha suspension interface compared to kombucha microbes resuspended without biosurfactants but persisted for longer than 24 h in contact with n-decane. We also demonstrate that Komagataeibacter in kombucha can produce elastic cellulosic biofilms using hydrocarbons from the oil interface as the sole source of carbon and energy. Thus Komagataeibacter and kombucha shows the potential of this system for producing valued bacterial cellulose through remediation of hydrocarbon waste.
... However, some authors used slightly lower temperatures for tea infusion (Cardoso et al., 2020;Gaggìa et al., 2019;. The amount of tea added varies from 0.15% (Miranda et al., 2016) to 1.5% (Barbosa et al., 2020) and the concentration of initial sugar varies between 50 g/L (Cardoso et al., 2020;Chakravorty et al., 2016) to 100 g/L (Abel & Andreson, 2020;Ansari et al., 2017Ansari et al., , 2019Barbosa et al., 2020;Jafari et al., 2020;Jakubczyk et al., 2020;Kaewkod et al., 2019;Wang et al., 2020). Malbaša et al. (2008) investigated initial sucrose concentrations of 50, 70, and 90 g/L, obtaining higher sugar consumption at a concentration of 70 g/L, as well as a high content of lactic acid. ...
Article
Kombucha is a beverage obtained by fermenting sweetened green or black tea with a symbiotic culture of bacteria and yeasts (SCOBY), which claims nutritional characteristics. As demand for kombucha increased, alternative extracts to green or black tea such as herbs, fruits, milk, agro-industrial materials started to be used in fermentation, giving rise to kombucha-like beverages. The literature review shows that the procedure and conditions used to obtain kombucha-like beverages are similar to the traditional fermentation. However, some additional steps may be necessary to prepare the raw material for its use as an alternative to green or black tea, the main approaches being highlighted in this review. Bioactive compounds (mainly phenolics) are considered one of the main attractions of kombucha due to their antioxidant characteristics. It is observed that, regardless of the extract used, the bioactive compounds (mainly phenolics) and also the antioxidant activity tend to increase during the fermentation of these beverages. Thus, the use of alternative raw materials to tea for the preparation of kombucha is viable and tends to serve a wide range of products according to different regions of the world. These new beverages have similar characteristics to the traditional beverage and respect the diversity of consumer market trends.
... On the last day of fermentation, the highest titratable acidity values were found in blackberry (BB) (18.42% w/v) and raspberry (RB) (16.19% w/v) samples, respectively (P<0·05 ; Table 1). Similarly, Chakravorty and coauthors [48] and Tu and coauthors [49] reported that titratable acidity increased depending on the fermentation time. The increase in titratable acidity was due to the fermentation of glucose to organic acids by microorganisms, especially lactic acid bacteria. ...
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Abstract In this study, physicochemical, microbiological, and sensory properties, antibacterial and antifungal effects of kombucha teas produced with some small berry fruits (blackberry, raspberry, and red goji berry) were investigated. During fermentation, titratable acidity and pellicle biomass weights increased whereas water activity, brix, viscosity, L* and b* values decreased. At the end of fermentation, the highest minerals determined in the samples were potassium and magnesium. Also, catechin and gallic acid were detected in all samples. Samples produced with blackberry were the most appreciated ones in all criteria. The highest antibacterial and antifungal effects were determined in samples containing blackberries on Staphylococcus aureus and Rhizopus nigricans (24.36 and 20.53 mm zone diameters). The antibacterial effect, MIC, and MBC values (0.023 and 0.016 mg/L) on Staphylococcus aureus. Regarding the antifungal effect, the MIC and MFC values were determined in tea produced with blackberry on Rhizopus nigricans with 0.035 mg/L, and 0.023 mg/L.
... Flavonoid compounds can increase due to the degradation of flavonoids and complex polyphenols in kombucha into smaller and simpler molecules. Chakravorty et al., 2016 research showed that the total concentration of polyphenols and kombucha flavonoids increased progressively over time of fermentation, it is also known that Candida tropicalis microorganisms are able to degrade polyphenols and flavonoid compounds resulting in an increase in the overall content observed. ...
Article
Shallots (Allium cepa) is an important aromatic plant, with a level of consumerity that is directly proportional to the increase in shallot skin waste. Whereas the skin of shallots contains flavonoids (quercetin) that are 3-5 times higher than the tubers. This research focuses on the use of shallot skin ingredients fermented by Symbiotic Culture of Bacteria and Yeast (SCOBY) into kombucha drinks. With the aim to explore the influence of long fermentation of shallot skin kombucha on the parameters of the chemical characteristics of pH and Total Titrable Acid (TTA); the presence of flavonoids; and organoleptic flavors, colors, aromas. The result is the length of fermentation affecting the decrease in the pH value, and had a very noticeable effect on the increase in the Total Titrable Acid value. Flavonoids were qualitatively tested by 3 reagents (10% NaOH, AlCl3 1%, H2SO4 judging by discoloration. At show all samples show positive results of flavonoid presence. The length of fermentation for organoleptic assessment has a significant effect on taste and aromas, but has no significant effect on the kombucha color. The recommendation for a good fermentation time with high acceptance is 8 days of fermentation.
... More recently in vitro and in vivo evidence suggest kombucha has health benefits that include, anti-microbial, antioxidant, detoxification, anti-tumour and immune-enhancing effects, along with enhancing gastrointestinal, hepatic cardiac and neurological function [1][2][3][4]. The microbial communities involved in the fermentation process produce a number of metabolites which make this tea beneficial to the human gut [5]. ...
Article
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Kombucha is a fermented tea made from a Symbiotic Culture of Bacteria and Yeast (SCOBY) with a long history of use as a health tonic. It is likely that most health benefits come from the tea and fermentation metabolites from specific microbial communities. Despite its growing importance as a functional health drink, the microbial ecosystem present in kombucha has not been fully documented. To characterize the microbial composition and biochemical properties of ‘The Good Brew’ original base kombucha, we used metagenomics amplicon (16S rRNA and ITS) sequencing to identify the microbial communities at the taxonomic level. We identified 34 genera with 200 microbial species yet described in kombucha. The dominance of organic acid producing microorganisms Acetobacter, Komagataeibacter and Starmerella are healthy for the human gut and their glucose metabolising activities have a putative role in preventing conditions such as diabetes and obesity. Kombucha contains high protein (3.31 µg/mL), high phenolic content (290.4 mg/100 mL) and low sugars (glucose: 1.87 g/L; sucrose 1.11 g/L; fructose: 0.05 g/L) as compared to green tea. The broad microbial diversity with proven health benefits for the human gut suggests kombucha is a powerful probiotic. These findings are important to improve the commercial value of kombucha and uncover the immense prospects for health benefits.
... xylinum) have been identified in kombucha [1]. During the fermentation process, acetic acid bacteria and yeast form biofilm on the surface of kombucha [2] and produce organic acids such as gluconic acid and glucuronic acids [3] that reduce the pH of kombucha [4] and increase the phenolic compound and the antioxidant activity because of degradation of phenolic compounds through hydroxy acids and ferulic acids [5]. ...
Article
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Kombucha is a fermented tea beverage with the addition of a kombucha starter called SCOBY (Symbiotic Culture of Bacteria and Yeast). This research aimed to know the microbiological, chemical and antibacterial activity from various concentrations of turmeric kombucha. The data result was analyzed by descriptive analysis with one factor of turmeric concentration (0.4%; 0.8%; 1.2%; 1.6%; 2%). The best treatment was selected using Multi-Criteria Decision-Making (MCMD) method with the Simple Additive Weighting (SAW) technique. The best treatment was obtained on turmeric kombucha 0.8%. Based on analysis, the best treatment is turmeric kombucha 0.8% with characteristics as follows: pH 2.92; total acid 0.28%; total phenol 147.45 μg GAE/ml; total sugar 8%, total microbial 2.5 x 10 ⁷ CFU/ml, inhibition zone diameters for E.coli 3.13 mm; whereas black tea kombucha has pH 2.81; total acid 0.58%; total phenol 716.02 μg GAE/ml; total sugar 7.83%, total microbial 1.3 × 10 ⁸ CFU/ml and inhibition zone diameters for E.coli 2.50 mm.
... Chakravorty et al. [22], used traditional culture-independent methods to explore the biofilm bacterial community and reported that Komagataeibacter sp. and Acetobacter sp. as the main bacterial genera present. ...
... These organic acids, along with the alcohols produced by the yeast, act as antimicrobial agents that inhibit the growth of undesirable microbes in kombucha [35]. The levels of polyphenols and flavonoids originally found in black tea increase progressively with fermentation, most likely due to the role of yeast in enzymatically degrading the polyphenols into smaller molecules, increasing the antioxidant activity of kombucha and stimulating the production of bacterial cellulose [36,37]. ...
Article
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Food fermentation has been practised since ancient times to improve sensory properties and food preservation. This review discusses the process of fermentation, which has undergone remarkable improvement over the years, from relying on natural microbes and spontaneous fermentation to back-slopping and the use of starter cultures. Modern biotechnological approaches, including genome editing using CRISPR/Cas9, have been investigated and hold promise for improving the fermentation process. The invention of next-generation sequencing techniques and the rise of meta-omics tools have advanced our knowledge on the characterisation of microbiomes involved in food fermentation and their functional roles. The contribution and potential advantages of meta-omics technologies in understanding the process of fermentation and examples of recent studies utilising multi-omics approaches for studying food-fermentation microbiomes are reviewed. Recent technological advances in studying food fermentation have provided insights into the ancient wisdom in the practice of food fermentation, such as the choice of substrates and fermentation conditions leading to desirable properties. This review aims to stimulate research on the process of fermentation and the associated microbiomes to produce fermented food efficiently and sustainably. Prospects and the usefulness of recent advances in molecular tools and integrated multi-omics approaches are highlighted.
... Продуцент представляет собой симбиотическую культуру, состоящую из 8-10 родов уксуснокислых бактерий, среди которых наиболее значимым является Komagateibacter, и 15-30 родов дрожжей -Zygosaccharomyces, Candida, Kloeckera и др. (видовой состав культуры детально приведен в работах [27,28]). Культуральная жидкость получена на полусинтетической питательной среде согласно [26] при дозировке инокулята 10%, возраст -9 сут. ...
Article
: Scaling biosynthesis of bacterial nanocellulose (BNC) allowed samples of composite paper with an increased proportion of BNC to be obtained. This work aims to study BNC samples and bleached soft wood kraft pulp (BSKP) composite paper with a ratio of components varying across a wide range: 10:90, 30:70, 50:50, 60:40, 70:30, 90:10. The method of paper manufacturing was chosen based on the determinations of strength and deformation properties of composite samples with the BNC:BSKP ratio of 20:80. Surface application of BNT on BSKP handsheet provided for an increase in the strength values (tear resistance – by 37%, burst index – by 17%) and deformation characteristics (tension stiffness – by 66%, fracture work – by 8%, breaking length – by 4%) compared to a reference sample. The formation of composites is confirmed in all samples. Scanning electron spectroscopy revealed that paper composites comprise interlaced micro BSKP and nano BNC fibres. As the proportion of BNC in composites elevated, densification of the structure was observed due to an increased fraction of cross-linked nanosized elements. IR spectroscopy indicated the resemblance of cellulose structure in all samples. It was found that an increase in the degree of polymerisation of composite paper is directly proportional to an increase in the BNC amount in the samples. The filtering ability of composite paper samples against microorganisms in the culture liquid of the Medusomyces gisevii Sa-12 producer was studied. It should be noted that yeast retention is achieved with 70% BNC in the paper composite. The presented properties of the new material determine prospects for its use in filtering microorganisms.
... The abundance of Candida was higher in HH samples (1.65%) compared to that in HX (0.69%) and QC (0.11%). Previous works showed that Candida in fermentation food could promote fermentation and had an excellent ability to produce many kinds of enzyme and flavor compounds, such as in kombucha tea fermentation (Chakravorty et al., 2016). Candida was also reported to be related to the production of ester and alcohols in Daqu (Yan et al., 2019). ...
Article
Light-flavor Baijiu often obtained using mixed Daqu - Houhuo (HH), Hongxin (HX), and Qingcha (QC) as starter culture for fermentation. These three types of low-temperature Daqu were incubated by traditional manual temperature control procedures. However, differences in their microbial communities and metabolite profiles remain largely unknown. Herein, microbial communities and metabolites in the three types of Daqu were compared using high-throughput sequencing and nuclear magnetic resonance analyses. Furthermore, the correlation between microbes and metabolites was constructed. Lactobacillus, Weissella were the dominant bacteria, whereas Pichia and Saccharomycopsis were the dominant fungi in all the three types of Daqu. The abundance of Lactobacillus was highest in HH (72.56%) and Weissella was highest in QC (32.62%). The abundance of Pichia was similar among three types of Daqu, while Saccharomycopsis and Lichtheimia showed the highest abundance in QC individually. Linear Discriminant Analysis (LDA) Effect Size (LEfSe) revealed that Lactobacillus, Acetobacter, and Bacillus were the main biomarkers in the three types of Daqu. Ethanol, glucose, proline, and lactate were identified as the most abundant metabolites. Furthermore, the metabolic functions of microbes were predicted, and amino acid metabolism, energy metabolism, and lipid metabolism were identified as the major metabolic pathways in Daqu. Correlation analysis indicated that lactate and acetate were negatively correlated with Lactobacillus, Acetobacter, and Bacillus. Antimicrobial compounds (i.e., betaine and choline) were negatively correlated with Brachybacterium, Corynebacterium, and Brevibacterium. The results shed light on the manual temperature control techniques for Daqu microbiome formation and provide new insights into managing the traditional fermentation process.
... This symbiotic culture, commonly known as Kombucha or tea fungus, is comprised of 10 genera of acetobacteria, which, in fact, produce a cellulosic gel-film, and about 25 genera of yeasts that provide a comfortable co-existence of BC-producing microorganisms. The composition of the culture has repeatedly been described in the literature [26,27]. ...
Article
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One of the ways to enhance the yield of bacterial cellulose (BC) is by using dynamic aeration and different-type bioreactors because the microbial producers are strict aerobes. But in this case, the BC quality tends to worsen. Here we have combined static culture with aeration in the biosynthesis of BC by symbiotic Medusomyces gisevii Sa-12 for the first time. A new aeration method by feeding the air onto the growth medium surface is proposed herein. The culture was performed in a Binder-400 climate chamber. The study found that the air feed at a rate of 6.3 L/min allows a 25% increase in the BC yield. Moreover, this aeration mode resulted in BC samples of stable quality. The thermogravimetric and X-ray structural characteristics were retained: the crystallinity index in reflection and transmission geometries were 89% and 92%, respectively, and the allomorph Iα content was 94%. Slight decreases in the degree of polymerization (by 12.0% compared to the control―no aeration) and elastic modulus (by 12.6%) are not critical. Thus, the simple aeration by feeding the air onto the culture medium surface has turned out to be an excellent alternative to dynamic aeration. Usually, when the cultivation conditions, including the aeration ones, are changed, characteristics of the resultant BC are altered either, due to the sensitivity of individual microbial strains. In our case, the stable parameters of BC samples under variable aeration conditions are explained by the concomitant factors: the new efficient aeration method and the highly adaptive microbial producer―symbiotic Medusomyces gisevii Sa-12.
... Kombucha is a fermented tea drink commonly consumed for its potential health benefits [1]. The fermentation occurs by providing Symbiotic Culture of Bacteria and Yeasts (SCOBY), a biofilm of cellulose containing the bacteria and yeasts, as a starter to sugary tea [2,3]. Kombucha yeast have been reported to include members of the Zygosaccharomyces and Brettanomyces genera [4]. ...
Article
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Kombucha is an increasingly popular functional beverage that has gained attention for its unique combination of phytochemicals, metabolites, and microbes. Previous chemical and microbial composition analyses of kombucha have mainly focused on understanding their changes during fermentation. Very limited information is available regarding nutrient profiles of final kombucha products in the market. In this study, we compared the major chemicals (tea polyphenols, caffeine), antioxidant properties, microbial and metabolomic profiles of nine commercial kombucha products using shotgun metagenomics, internal transcribed spacer sequencing, untargeted metabolomics, and targeted chemical assays. All of the nine kombucha products showed similar acidity but great differences in chemicals, metabolites, microbes, and antioxidant activities. Most kombucha products are dominated by the probiotic Bacillus coagulans or bacteria capable of fermentation including Lactobacillus nagelii, Gluconacetobacter, Gluconobacter, and Komagataeibacter species. We found that all nine kombuchas also contained varying levels of enteric bacteria including Bacteroides thetaiotamicron, Escherischia coli, Enterococcus faecalis, Bacteroides fragilis, Enterobacter cloacae complex, and Akkermansia muciniphila. The fungal composition of kombucha products was characterized by predominance of fermenting yeast including Brettanomyces species and Cyberlindnera jadinii. Kombucha varied widely in chemical content assessed by global untargeted metabolomics, with metabolomic variation being significantly associated with metagenomic profiles. Variation in tea bases, bacteria/yeast starter cultures, and duration of fermentation may all contribute to the observed large differences in the microbial and chemical profiles of final kombucha products.
... Some authors also report the use of previously fermented tea as starters, which can be used to start the fermentation process ( Kombucha has interesting nutritional valor, mainly due to the benefits of Camellia sinensis that are already well described in many literatures. As for the characteristic acidity of the beverage, it may vary according to the time and speed of fermentation and occurs due to the production of organic acids, especially acetic acid (Chakravorty et al., 2016;Vitas et al., 2018). Acetic bacteria, the major part of the SCOBY, synthesize acetic acid from the ethanol produced by yeasts. ...
Article
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Kombucha is a millennial beverage with great potential due to its functional claims. The infusion of black or green tea leaves (Camellia sinensis) and sugar is fermented by a symbiotic culture of bacteria and yeasts (SCOBY) resulting in an acidic and lightly carbonated beverage, kombucha. It offers in its composition phytoconstituents with relevant nutritional valor, among these, flavonoids that stand out for their antioxidant, anti-inflammatory characteristics and their association with decreasing the risks of various diseases. Previous studies in vivo and in vitro have shown promising results using kombucha as a functional beverage. Those studies promote the search for alternative raw materials for the production of kombucha, in addition, new ingredients interfere in the production, constitution, and nutritional potentialities of the beverage, as well as its functionality in the face of diseases. Thus, this graphical review compiles relevant scientific data on kombucha involving its origin, production, nutritional potential, and possible health benefits associated with its consumption.
... The relative dominance of yeast genera, such as Zygosaccharomyces, Brettanomyces/Dekkera, Schizosaccharomyces, Saccharomyces, and Pichia, varies in accordance with the geographical variants of KMC (Jayabalan et al., 2014). Lactic acid bacteria are involved in the fermentation process in some KMC ecotypes (Chakravorty et al., 2016;Coton et al., 2017). The most beneficial genera detected in KMC samples were Bacteroides and Prevotella, which are known as dominant human gut microbiota members (Lavefve et al., 2021). ...
Article
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Humankind has entered a new era of space exploration: settlements on other planetary bodies are foreseen in the near future. Advanced technologies are being developed to support the adaptation to extraterrestrial environments and, with a view on the longer term, to support the viability of an independent economy. Biological processes will likely play a key role and lead to the production of life-support consumables, and other commodities, in a way that is cheaper and more sustainable than exclusively abiotic processes. Microbial communities could be used to sustain the crews’ health as well as for the production of consumables, for waste recycling, and for biomining. They can self-renew with little resources from Earth, be highly productive on a per-volume basis, and be highly versatile—all of which will be critical in planetary outposts. Well-defined, semi-open, and stress-resistant microecosystems are particularly promising. An instance of it is kombucha, known worldwide as a microbial association that produces an eponymous, widespread soft drink that could be valuable for sustaining crews’ health or as a synbiotic (i.e., probiotic and prebiotic) after a rational assemblage of defined probiotic bacteria and yeasts with endemic or engineered cellulose producers. Bacterial cellulose products offer a wide spectrum of possible functions, from leather-like to innovative smart materials during long-term missions and future activities in extraterrestrial settlements. Cellulose production by kombucha is zero-waste and could be linked to bioregenerative life support system (BLSS) loops. Another advantage of kombucha lies in its ability to mobilize inorganic ions from rocks, which may help feed BLSS from local resources. Besides outlining those applications and others, we discuss needs for knowledge and other obstacles, among which is the biosafety of microbial producers.
... fermenting vessel geometry, time, and temperature), and the ingredients used (e.g. sugar concentration and tea type) (Chakravorty, Bhattacharya, Chatzinotas, Chakraborty, Bhattacharya, & Gachhui, 2016;Coton et al., 2017). The main microorganisms found in SCOBY and kombucha are acetic acid-producing bacteria (e.g. ...
Article
This study shows the changes in physicochemical and microbiological composition, and in the phenolic profile of black tea kombucha during fermentation. In addition, the antimalarial potential of the kombucha was evaluated. Ultra-performance liquid chromatography-mass spectrometry multiplex analysis (UPLC-MSE) results revealed a 1.7 log2 fold-change increase in phenolics with the fermentation time, with emphasis on the increase of phenolic acids (0.3 log2 fold-change). Over time there was degradation of flavonoids such as nepetin, hesperidin and catechin 5-O-gallate, to the detriment of the increase in phenolic acids such as gallic acid and cinnamic acid. In addition, black tea kombucha presented antiplasmodic activity against the 3D7 (sensitive chloroquine) and W2 (resistant to chloroquine) strains. Therefore, important changes in the black tea kombucha phenolic profile take place during fermentation, which may help in the development of kombuchas with higher bioactive potential and contribute to a better understanding of the kombucha fermentation process.
... xylinus, K. kombuchae), Acetobacter (A. aceti, A. pasteurianus, A. nitrogenifigens), Gluconacetobacter (G. sacchari) are major AAB strains, while strains of Saccharomyces (S. cerevisiae) and non-Saccharomyces (Candida spp., Schizosaccharomyces spp., Dekkera spp., Brettanomyces spp.) are leading yeasts representatives [30,47,48]. Despite the large number of studies using SCOBY, a relatively large number of articles do not provide clear data on the bacterial and yeasts composition of the used consortium [34,[49][50][51][52]. ...
Article
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Kombucha is a low alcoholic beverage with high content of bioactive compounds derived from plant material (tea, juices, herb extracts) and metabolic activity of microorganisms (acetic acid bacteria, lactic acid bacteria and yeasts). Currently, it attracts an increasing number of consumers due to its health-promoting properties. This review focuses on aspects significantly affecting the bioactive compound content and biological activities of Kombucha tea. The literature review shows that the drink is characterized by a high content of bioactive compounds, strong antioxidant, and antimicrobial properties. Factors that substantially affect these activities are the tea type and its brewing parameters, the composition of the SCOBY, as well as the fermentation parameters. On the other hand, Kombucha fermentation is characterized by many unknowns, which result, inter alia, from different methods of tea extraction, diverse, often undefined compositions of microorganisms used in the fermentation, as well as the lack of clearly defined effects of microorganisms on bioactive compounds contained in tea, and therefore the health-promoting properties of the final product. The article indicates the shortcomings in the current research in the field of Kombucha, as well as future perspectives on improving the health-promoting activities of this fermented drink.
... In addition, but in significantly smaller quantities, there are bacteria of the families Paenibacillaceae, Staphylococcaceae, Streptococcaceae, Lachnospiraceae, Bacteroidaceae, and Bifidobacteriaceae. About 30 species of fungi have been described, but yeasts of the Saccharomycetaceae (with a predominance Zygosaccharomyces spp. or Candida spp.), Schizosaccharomycetaceae (Schizosaccharomyces spp.), and Pichiaceae (Brettanomyces spp.) families prevail [4][5][6][7][8][9]. ...
Article
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Fungi Eurotium spp. are the main biological agents that ferment the leaves of the Camellia sinensis tea bush to form a popular food product, postfermented tea. The fungus E. cristatum, stored in the collection of the Gause Institute of New Antibiotics under the number INA 01267, was isolated and identified from a briquette of Fujian Chinese tea. The species identification was carried out based on morphocultural characteristics and DNA sequencing. This study is aimed at determining the feasibility of making postfermented herbal teas using E. cristatum and to evaluate their quality. Autofermented herbal teas from Chamaenerion angustifolium (fireweed) and Malus domestica (apple tree) served as the starting material for this study. The change in the concentration of phenolic compounds, organic acids, sugars, and free amino acids was observed for herbal teas subjected to postfermentation with E. cristatum INA 01267. It was found that the E. cristatum INA 01267 strain does not have antimicrobial activity and does not form mycotoxins, which is an indicator of food safety.
... This cellulosic mass, as well as previously fermented tea can be used as a starter for subsequent brews (Jayabalan et al., 2014). The symbiotic culture is formed mainly by acetic acid bacteria (Komagataeibacter, Gluconobacter and Acetobacter), lactic acid bacteria (Lactobacillus, Lactococcus) and yeasts (Schizosaccharomyces pombe, Saccharomycodes ludwigii, Kloeckeraapiculata, Saccharomyces cerevisiae, Zygosaccharomyces bailii, Torulaspora delbrueckii, Brettanomyces bruxellensis) (Chakravorty et al., 2016;Villarreal-Soto et al., 2018). ...
Article
Plant bioactive compounds have been studied mainly for their beneficial antioxidant properties. Kombucha is a fermented beverage traditionally obtained from fermentation of sweetened black or green tea by a characteristic consortium of yeasts and bacteria. The beverage naturally contains bioactive compounds from teas and their synthesis can be increased during fermentation. This review aims to explore the different bioactive compounds found in kombucha from different substrates, as well as the factors that influence on their synthesis and their amount in the final product. The results suggest phenolic compounds are the main bioactive compounds in kombucha. The substrate type contributes the most to increasing the content of bioactive compounds in the final product; fermentation time and type of sugar also increase the amount of these compounds. Further research suggestions include the combination of strategies to increase bioactive compounds in kombucha, quantification and characterization of the isolated compounds. Free access https://authors.elsevier.com/a/1emYm16Ds1s9uR
... Fermentation of kombucha tea involves metabolic activities between yeasts and acetic acid bacteria that utilize substrates in different ways (Teoh et al., 2004;Chakravorty et al., 2016;Jafari et al., 2021). The metabolic relationship of these microorganisms during fermentation produces beneficial organic acids and other substances such as acetic, gluconic acid, glucuronic acid, citric acid, lactic acid, malic acid, succinic acid, saccharic acid, pyruvic acid, sugars, vitamins, and amino acids (Jayabalan et al., 2014;Lee et al., 2021). ...
Article
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Traditional kombucha tea was prepared by black tea leaves before fermentation with symbiotic microorganisms for 15 days. In this study, kombucha was prepared through a combination with medicinal plant extracts of T. catappa (KT) and A. marmelos (KA) to enhance a number of beneficial aspects. The results revealed that the phenolics, flavonoids, antioxidants and six organic acids, namely glucuronic, gluconic, D-saccharic acid 1,4-lactone (DSL), acetic, ascorbic, and succinic acids, in kombucha combined with the medicinal plant extracts resulted in the production of substances with greater beneficial properties than traditional kombucha tea. The viability of colorectal cancer cells (Caco-2) after treatment with KT and KA was suppressed in a dose-dependent manner, while DNA fragmentation in Caco-2 cells was induced via the apoptosis mechanism. This process involved the apoptosis pathways related to the intrinsic apoptosis pathway, which was activated by KT and KA through the mitochondrial-dependent pathways including cytochrome c release and Bcl-2 suppression, and activation of caspases-9 and caspases-3. The findings of this study support the enhanced beneficial properties of traditional kombucha tea through a combination with medicinal plants. This outcome would also support the consideration of natural supplementary kombucha beverages as medicinal food products in the prevention of colorectal cancer.
... Some studies helped to understand the management of the main non-volatile parameters related to taste (meaning residual sugar and acidity) (Chen and Liu, 2000;Chakravorty et al., 2016;Tran et al., 2020a), but few studies have attempted to analyze kombucha's volatile composition (Savary et al., 2021;Zhang et al., 2021) by providing first insights into the type and quantity of volatile compounds (aldehyde, ketones, alcohols, fatty acids and esters mainly). In the study of Zhang et al. (2021), Gas Chromatography/Mass Spectrometry (GC/MS) was performed on 6-day kombuchas and led to the detection of 22 volatile compounds (including ethyl octanoate, ethyl guaiacol and phenylethyl ethanol) common to all samples. ...
Article
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Microbiological, chemical, and sensory analyses were coupled to understand the origins of kombucha organoleptic compounds and their implication in the flavor of the kombucha beverage. By isolating microorganisms from an original kombucha and comparing it to monocultures and cocultures of two yeasts (Brettanomyces bruxellensis and Hanseniaspora valbyensis) and an acetic acid bacterium (Acetobacter indonesiensis), interaction effects were investigated during the two phases of production. 32 volatile compounds identified and quantified by Headspace-Solid Phase-MicroExtraction-Gas Chromatography/Mass Spectrometry (HS-SPME-GC/MS) were classified according to their origin from tea or microorganisms. Many esters were associated to H. valbyensis, while alcohols were associated to both yeasts, acetic acid to A. indonesiensis, and saturated fatty acids to all microorganisms. Concentration of metabolites were dependent on microbial activity, yeast composition, and phase of production. Sensory analysis showed that tea type influenced the olfactive perception, although microbial composition remained the strongest factor. Association of B. bruxellensis and A. indonesiensis induced characteristic apple juice aroma.
... www.nature.com/scientificreports/ Kombucha tea during the course of its fermentation (0, 7, 14, and 21 days) and observed a high tendency to increase especially after the 7th days, which may be due to the higher microbial diversity achieved by that time 27 . ...
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Kombucha is a beverage made by fermenting sugared tea using a symbiotic culture of bacteria belonging to the genus Acetobacter, Gluconobacter, and the yeasts of the genus Saccharomyces along with glucuronic acid, which has health-promoting properties. The paper presents the evaluation of ferments as a potential cosmetic raw material obtained from Yerba Mate after different fermentation times with the addition of Kombucha. Fermented and unfermented extracts were compared in terms of chemical composition and biological activity. The antioxidant potential of obtained ferments was analyzed by evaluating the scavenging of external and intracellular free radicals. Cytotoxicity was determined on keratinocyte and fibroblast cell lines, resulting in significant increase in cell viability for the ferments. The ferments, especially after 14 and 21 days of fermentation showed strong ability to inhibit (about 40% for F21) the activity of lipoxygenase, collagenase and elastase enzymes and long‐lasting hydration after their application on the skin. Moreover, active chemical compounds, including phenolic acids, xanthines and flavonoids were identified by HPLC/ESI–MS. The results showed that both the analyzed Yerba Mate extract and the ferments obtained with Kombucha may be valuable ingredients in cosmetic products.
... The microbial community in kombucha is an excellent vehicle for transforming the fermentation process and is mainly composed of yeast and acetic bacteria. The microorganisms involved maintain dynamic relationships of cooperation and competition, allowing different ecological succession processes to occur over the fermentation time [30]. In general, the microbial community initiates medium transformation through the action of yeasts, which orchestrate the breakdown of sucrose into glucose and fructose through the action of invertases released in the liquid. ...
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Fermentation is one of the oldest biotechnological tools employed by mankind. Fermenting food gives them better sensory and nutritional qualities, the latter including vitamins, phenolic compounds, antioxidants, and antimicrobials. Kombucha is the result of the fermentation of a sweetened Camellia sinensis infusion by the action of a symbiotic community of yeasts and bacteria organized in a cellulosic biofilm called SCOBY and has gained great prominence among fermented foods and beverages, with a considerable increase in its popularity in the last decade, both among consumers and within the scientific community. This is explained by the particular functional and microbial characteristics of this beverage, such as its antioxidant and antimicrobial potential, long-term stable microbial communities, its suitability for fermentation under different conditions of time and temperature, and amenability to other carbon sources besides sucrose. Thus, this review aims to present and discuss the functional, microbial, and physicochemical aspects of kombucha fermentation, covering the many challenges that arise in its production, in domestic, commercial, and legislation contexts, and the next steps that need to be taken in order to understand this drink and its complex fermentation process.
... This fermentation is carried out by a characteristic consortium of yeast and bacteria called SCOBY (symbiotic culture of bacteria and yeast) [5,6]. The microbiological composition of a consortium can vary depending on factors such as climate, geographic location, and the environment used for the fermentation process [7,8]. ...
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The issues of biological conversion of products of processing plant raw materials remain invariably relevant. The development of processing secondary resources allows to increase the efficiency of food production, solving environmental problems and to contribute to ensuring food security. The paper presents data on the results of studies of biotechnological properties of yeast cultures Zygosaccharomyces kombuchaensis sp. and bacteria Gluconoacetobacter xylinus (Brown 1886) Yamada et al 1998 , constituting a symbiotic culture called SCOBY (symbiotic culture of bacreties and yeasts), adapted and cultivated in the Krasnodar Territory with the aim of their further use for biological conversion of fruit and berry raw materials and secondary raw materials for the production of functional drinks. The optimal values for the cultivation of the studied cultures were established: pH – 6.5, temperature – for Zygosaccharomyces kombuchaensis sp. minimum growth temperature t = +15-20 °С, maximum – t = +45-50 °С, for Gluconoacetobacter xylinus (Brown 1886) Yamada et al 1998 minimum growth temperature t = +10- 25 °С, maximum – t = +45-50 °C; the content of reducing substances is 10-15 %. The data obtained will be used to develop biotechnological processes for the production of functional drinks.
... As for the AAB, it has been reported that the symbiotic relationships between these bacteria with yeasts result in higher cellulose production yields, due to the natural and stable conformation of the microbial community or consortium and the synergistic and coordinated metabolism of the different microorganisms allowing an efficient activity of the cellulose synthase machinery [119]. ...
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The symbiotic community of bacteria and yeast (SCOBY) of Kombucha beverage produces a floating film composed of bacterial cellulose, a distinctive biobased material. In this work, Kombucha fermentation was carried out in six different herbal infusions, where SCOBY was able to synthesise cellulosic films. Infusions of black and green tea, yerba mate, lavender, oregano and fennel added with sucrose (100 g/l) were used as culture media. In all cultures, film production resulted in a maximum after 21 days. Yield conversion, process productivity and antioxidant activity were quantified. Macroscopic and microscopic features of films were determined based on electronic microscopy, calorimetric and mechanical properties and hydration behaviour. Native films from yerba mate had a remarkable antioxidant activity of 93 ± 4% of radical inhibition due to plant polyphenols, which could prevent food oxidation. Results revealed that films retained natural bioactive substances preserving important physicochemical properties, essential for developing active materials.
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Background In order to balance human health and environmental sustainability, plant-based diets have been attracting increasing attention. Plant-based fermented foods are produced using vegetables or fruits as the main raw materials. Thereafter, microorganisms and their metabolites convert these into the final products, which are often covered by biofilms during production and storage. The biofilms are composed of various microbial flora and extracellular metabolites produced during fermentation, which is generally considered as a shortcoming of fermentation. However, growing evidence suggests that these complex microbial ecosystems are sources of both probiotic substances and antimicrobial compounds, which can benefit health and improve food processing. Scope and approach Advanced studies have established relationships between the representative film-forming microorganisms in biofilms and the quality and safety of fermented foods. Inhibition and elimination strategies have also been proposed by targeting biofilm control methods from the food and medical industries towards the formation mechanisms and compositional characteristics of the biofilms. Key findings and conclusions Based on the data generated from previous control measures, this review introduces the key elements pertaining to biofilm formation as function of substrate and metabolic conditioning and summarizes the potential benefits of biofilms, especially in plant-based fermented foods. Further, this review highlights strategies surrounding the utilization and modulation of biofilms in plant-based fermented foods. The re-design and functionalization of biofilms are therefore discussed for a wide range of applications.
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Kombucha beverage produced through fermentation of sugared tea using bacteria and yeast has gained attention for its beneficial health benefits. However, the cost linked to the raw materials often increases the upstream process expenses, thereby the overall operating expenditures. Thus, there is a need to explore alternative waste and cost-effective raw materials for Kombucha fermentation. The present study, compared the physico-chemical and microbial growth pattern of Kombucha beverage production using tea waste from the tea processing industries with that of the green/black tea, reporting similar trends irrespective of its type. Further, the amplicon sequencing of 16S rRNA showed dominant presence of Komagataeibacter rhaeticus and high throughput sequencing of ITS1 confirmed the presence of yeast species similar to Brettanomyces bruxellensis in the tea waste based Kombucha beverage. Appreciable amount of carbohydrates (8.5/100 g) and energy (34 kcal/100 g) with appropriate organoleptic properties favourable for human consumption were also observed during the nutritional content and qualitative property assessment. The overall study showed a broad taxonomic and functional diversity existing during Kombucha fermentation process with tea waste to maintain a sustained eco-system to facilitate cost-effective beverage production with desired properties for safe consumption.
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Background Over the past two decades, the global beverage industry has developed rapidly. Especially, the global tea beverage market reached 37 million tons in 2016, an increase of 40% in five years, and is estimated to reach 45 million tons by 2021. According to the forecast of Statista, a business data platform, the global tea beverage market is estimated to be worth about US $44.3 billion by 2021. In the last 5 years, remarkable progress has been made in the research on tea beverages, including liquid tea beverage, instant tea powder, tea concentrate, kombucha, tea wine and other fermented tea beverages. Scope and approach This article highlights and critically reviews the recent advances in tea beverage research with specific focus on the processing methods for flavor enhancement. An overview on the innovation and development of tea drinks over the world is provided. Key findings and conclusion Cold extraction, ultrasonic extraction and dynamic extraction have been employed in the production of tea beverage. Tannase, β-glucosidase, pectinase, amylase, lyticase and protease have been used to improve the flavor of tea beverage. Chromatography and electrochemical fingerprints and other analytical techniques have been used in flavor evaluation of tea beverages. Many new types of fermented tea beverages have been developed.
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Kombucha is a drink produced by fermentation of sweetened tea due to symbiotic relationship between yeast and acetic acid bacteria species. In this study; pH value, total acidity, alcohol, total phenolic compounds quantities, caffein and some individual compounds contents of kombucha drinks produced using white, black and green tea were determined. At the end of the fermantation, pH and total acidity (% acetic acid) values of kombuchas including white, black and green tea were found 3,11; 3.22; 3.16 and 8,9; 9,2; 9,0, respectively. Total phenolic compund content of kombuchas produced with white tea (736,1 mg GAE/L) was higher than others. The highest amount of compounds analyzed in the kombucha samples were identified as caffeine. Gallic acid (4,76±1,06 mg/L), caffeine (63,47±4,64 mg/L) and epicatechin (1,59±0,06 mg/L) quantities of kombuchas produced with using white tea were found higher than kombuchas produced with using black and green tea.
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Yeasts have remained one of the important microbes because they represent excellent scientific model systems of eukaryotic origin and find numerous biotechnological applications. Yeasts can be considered as one of the earliest domesticated microorganisms involved in ancient fermentation processes without even human’s understanding. For centuries, mankind has exploited their potential to produce fermented food and alcoholic beverages and for various other applications. Research in the areas of yeast diversity and applications has shown an unprecedent growth in recent times all across the globe. Exploration of yeasts in the natural habitats has resulted in the description of novel yeast species from India, while many researchers have used them for various biotechnological applications. This chapter is thus intended to give a brief account on the progress of yeast research in the field of diversity, taxonomy, and their applications in the production of ethanol, biodiesel or yeast lipids, enzymes, traditional fermented food and beverages, probiotics, xylitol, pullulans, and biosurfactants to mention a few. Their application in bioremediation, biosorption, and plant growth promotion has also been briefly discussed. Considering a rich history of yeast research in India, which is still the tip of the iceberg, the field offers a vast potential for future research. This chapter would also be helpful in understanding the established strong yeast research grounds and as to how these interesting organisms can further be utilized for future collaborative research in India.
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