Optimizing Glucuronic Acid Synthesis in Kombucha Production: A Comprehensive Study on Process Parameters

Abstract

Kombucha, a traditional fermented tea beverage, is gaining popularity for its health benefits due to its bioactive compounds, especially glucuronic acid, known for detoxifying and hepatoprotective properties. Despite its significance, factors influencing glucuronic acid levels are not well understood. This study investigated the impact of initial sugar concentrations (4%, 6%, 8%) and tea types (black, green, oolong) on glucuronic acid synthesis during kombucha fermentation over 20 days.

Results showed that pH dropped rapidly in the first three days, then stabilized before declining further until day 20, across all samples. Total soluble solids, measured in Brix values (oBx), decreased quickly initially, indicating microbial consumption, then stabilized. Glucuronic acid concentration, measured using an enzymatic kit, peaked around day 14, with black tea kombucha at higher sugar concentrations achieving up to 0.176 mg/ml, being also significantly higher than green and oolong teas.

A subsequent HPLC analysis revealed variations in the metabolite concentrations of some samples, with black tea kombucha showing the highest levels of acetic acid and glucose, while green tea kombucha had the highest ethanol content.

Focus groups were also performed, which indicated that different tea compositions and fermentation lengths influenced consumer acceptance, showcasing a wide range of opinions about the product.

In summary, initial sugar concentration and tea type significantly affect glucuronic acid levels in kombucha. Optimizing these parameters can enhance the beverage’s health benefits and sensory qualities, contributing to advancements in food science and consumer health.

Popular Abstract

Imagine discovering that your daily glass of kombucha, that tasty and refreshing fermented tea beverage, could become even healthier simply by adjusting some of its ingredients. That is exactly what our research delved into – exploring how the tea type, amount of sugar, and fermentation time used in brewing kombucha can maximize its health benefits. We focused on increasing glucuronic acid, a natural substance known for detoxifying properties.

In this project, kombucha was brewed using black, green, and oolong tea, each with three different sugar concentrations over a period of 20 days. Small group discussions were also conducted to see how potential consumers would like the kombucha. The results were nothing short of fascinating! It was revealed that black tea kombucha was the ultimate winner, consistently producing the highest levels of glucuronic acid, especially at higher sugar concentrations. In contrast, green tea produced the lowest levels despite its popularity for health benefits, suggesting that tea type significantly influences the health-boosting properties of kombucha. However, the overall levels observed were still much less than expected, based on other similar studies. This suggests that other factors were at play, like fermentation temperature and the type of microbes in the kombucha.

One surprising discovery was that black tea samples displayed a unique sugar spike midway through the fermentation process. This opens doors to further investigations on how kombucha microbes behave in black tea fermentation. Another surprise was that green tea kombucha brewed for 14 days was the best received among all the tea types. Given that most kombucha available on the market is made from black tea, this signals an exciting untapped market potential for green tea kombucha.

By attempting to fill the knowledge gap of increasing glucuronic acid in kombucha, our study addresses the need to understand how the different factors of kombucha brewing interact to achieve the maximum health benefits. With kombucha's growing popularity as a functional beverage, enhancing its beneficial effects and taste can make it an even better product for consumers.

In summary, our research highlights the significant impact of tea types and sugar concentrations on the glucuronic acid content in kombucha. By selecting the right ingredients, brewers can enhance the overall wellness of this popular drink. However, even if this is a good approach, there are still many unknowns regarding glucuronic acid – what is the most critical parameter? are there any minimum levels we should consume? The possibilities to keep contributing to the topic are endless!

• author: Goh, Luo Lin and Yanez Fernandez, Amanda Paz
• supervisor: Borbala Erdei; Nicholas Rosenstock
• organization: Food Technology and Nutrition (M.Sc.)
• course: KLTM02 20241
• year: 2024
• type: H2 - Master's Degree (Two Years)
• subject: Technology and Engineering
• keywords: Kombucha, glucuronic acid, tea variety, sugar concentration, optimizing fermentation, acetic acid, HPLC, consumer acceptance, food engineering, nutrition and food chemistry
• language: English
• id: 9162604
• date added to LUP: 2024-06-14 13:28:27
• date last changed: 2024-06-14 13:28:27