A Toxic Hepatitis Caused the Kombucha Tea – Case Report

Changes in the chemical compositions and biological properties of kombucha beverages made from black teas and pineapple peels and cores

Several raw materials have been used as partial supplements or entire replacements for the main ingredients of kombucha to improve the biological properties of the resulting kombucha beverage. This study used pineapple peels and cores (PPC), byproducts of pineapple processing, as alternative raw materials instead of sugar for kombucha production. Kombuchas were produced from fusions of black tea and PPC at different ratios, and their chemical profiles and biological properties, including antioxidant and antimicrobial activities, were determined and compared with the control kombucha without PPC supplementation. The results showed that PPC contained high amounts of beneficial substances, including sugars, polyphenols, organic acids, vitamins, and minerals. An analysis of the microbial community in a kombucha SCOBY (Symbiotic Cultures of Bacteria and Yeasts) using next-generation sequencing revealed that Acetobacter and Komagataeibacter were the most predominant acetic acid bacteria. Furthermore, Dekkera and Bacillus were also the prominent yeast and bacteria in the kombucha SCOBY. A comparative analysis was performed for kombucha products fermented using black tea and a fusion of black tea and PPC, and the results revealed that the kombucha made from the black tea and PPC infusion exhibited a higher total phenolic content and antioxidant activity than the control kombucha. The antimicrobial properties of the kombucha products made from black tea and the PPC infusion were also greater than those of the control. Several volatile compounds that contributed to the flavor, aroma, and beneficial health properties, such as esters, carboxylic acids, phenols, alcohols, aldehydes, and ketones, were detected in kombucha products made from a fusion of black tea and PPC. This study shows that PPC exhibits high potential as a supplement to the raw material infusion used with black tea for functional kombucha production.

Advances in Kombucha Tea Fermentation: A Review

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.

Effects of supplementation with kombucha and green banana flour on Wistar rats fed with a cafeteria diet

Introduction

With the increase of chronic diseases as a consequence of the population's eating habits, there is also a growing interest in foods rich in bioactive compounds capable of mitigating these diseases. Thus, this study aimed to evaluate the effects of supplementation with kombucha and green banana flour (GBF) on Wistar rats fed with cafeteria diet (CAF).

Methods

The animals were randomized into five groups of seven animals each, which were fed with the following diets: Treatment 1 (T1): Control treatment/commercial feed; Treatment 2 (T2): cafeteria diet (CAF); Treatment 3 (T3): CAF + kombucha; Treatment 4 (T4): CAF + green banana flour (GBF); Treatment 5 (T5): CAF + GBF + kombucha. Daily weight gain, daily food consumption, feed conversion, blood glucose, total cholesterol and fractions, triglycerides, liver enzymes, antioxidant activity, and body composition were evaluated.

Results

T5 presented lower feed intake and less weight gain. Liver histology revealed vacuolization in all treatments except T1, which was confirmed by the results of liver enzymes. There was no increase in blood glucose, and changes were observed in the lipid profile of the animals. T1 had the lowest body fat and the highest protein levels. Differences were observed for the antioxidant capacity in the liver of animals among treatments.

Conclusion

The intake of cafeteria diet altered the lipid and liver profile of the animals and the consumption of kombucha and GBF did not prevent these changes. The high polyphenols level of kombucha did not exert a hepatoprotective effect as an antioxidant. However, this supplementation generated greater satiety in the animals, leading to less weight gain until the end of the experiment.