Standardization, Fermentation, and pH-Based Stability Assessment of Kombucha from Gambyong Kemuning Green Tea

Abstract

This study aims to conduct the standardization, fermentation,
and stability assessment based on pH of kombucha made from
Gambyong Kemuning green tea (Camellia sinensis L).
Kombucha is widely known for its health benefits; however,
the standardization of herbal kombucha products still requires
further research. This study employed methods including
determination, simplicia preparation, simplicia
standardization, extraction using the infusion method, and the
preparation and standardization of kombucha. The results of
the simplicia standardization test showed a drying loss of
4.6%, moisture content of 6.12%, and total ash content of
3.61%, all of which meet the recommended standards to
prevent microbial growth and contamination. In addition,
heavy metal and ethanol tests indicated that both the infusion
and kombucha are safe for consumption. The pH test
conducted over 14 days of fermentation showed values within
the safe range, between 4.2 and 2.5, during the first 10 days.
However, on days 11 to 14, the pH dropped below the safe
limit, indicating an excessive acetic acid content that could
pose a health risk. In conclusion, Gambyong Kemuning green
tea kombucha demonstrated promising results in terms of
standardization and safety, but strict monitoring of
fermentation duration is necessary to maintain a stable and
safe pH for consumers.