Jeollanamdo Agricultural Research and Extension Services, Jeollanamdo, Republic of Korea.
Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju, Republic of Korea.
J Food Sci. 2024 Nov;89(11):7916-7927. doi: 10.1111/1750-3841.17428. Epub 2024 Oct 4.
The objective of this study was to optimize the microbial and ingredient composition of kombucha for enhanced production of gluconic acid (GA). Fourteen strains of Komagataeibacter spp. and one yeast strain of Dekkera sp. were isolated from kombucha. Among them, Komagataeibacter swingsii SS1 (SS1) and Komagataeibacter saccharivorans SS11 (SS11) were selected for their high GA production. A rapid reduction of pH, high GA content relative to acetic acid, and high cellulose production were observed in the tea infusion fermented by the microbial consortium (SS1 + SS11 + Dekkera bruxellensis Y24). From the correlation between the materials composition and quality indicators of kombucha, the decrease in pH was the most critical quality indicator of kombucha and the most closely related to GA content. Maximal GA production (11.7 mg/mL) was obtained under the conditions of 1% (w/v) tea extract, 8.5% (w/v) glucose, and 1.5% (v/v) ethanol through the optimization of materials composition by response surface methodology. The GA content of kombucha was enhanced threefold in comparison to general kombucha by fermentation with Komagataeibacter spp. and optimization of the composition of the ingredients. Overall, this study showed that a specific microbial consortium and materials composition could be established by correlation analysis among the ingredients, which results in increased GA levels in kombucha. These findings offer valuable foundational data for both commercial production and quality control of kombucha.
本研究旨在优化康普茶的微生物和成分组成，以提高葡萄糖酸（GA）的产量。从康普茶中分离出 14 株Komagataeibacter spp.和 1 株酵母Dekkera sp.。其中，Komagataeibacter swingsii SS1（SS1）和 Komagataeibacter saccharivorans SS11（SS11）因其高 GA 产量而被选中。在微生物共混物（SS1 + SS11 + Dekkera bruxellensis Y24）发酵的茶浸液中，观察到 pH 值迅速降低、GA 含量相对乙酸高、纤维素产量高。从康普茶的物质组成与质量指标的相关性来看，pH 值降低是康普茶最重要的质量指标，与 GA 含量最密切相关。通过响应面法优化材料组成，在 1%（w/v）茶提取物、8.5%（w/v）葡萄糖和 1.5%（v/v）乙醇的条件下，获得了最大的 GA 产量（11.7 mg/mL）。与一般康普茶相比，通过 Komagataeibacter spp.发酵和成分组成优化，康普茶的 GA 含量提高了三倍。总的来说，这项研究表明，通过对成分之间的相关性分析，可以建立特定的微生物共混物和物质组成，从而提高康普茶中的 GA 水平。这些发现为康普茶的商业生产和质量控制提供了有价值的基础数据。
