Characteristics of Kombucha fermentation on medicinal herbs of butterfly wing
Abstract
The research was conducted to observe and evaluate the characteristics of kombucha fermentation for medicinal herbs of butterfly wing. This study was designed by comparing between the black tea control usually used in kombucha production and butterfly wing herb to better understand the characteristics of fermentation that butterfly wing kombucha tea was undergoing. Observable and evaluated characteristics include changes in pH, titratable acidity, yeast count and ethanol content. Black tea control can be seen to have a much lower pH count overall which is about 3.4 to 2.7 but with a sudden rise in pH to 3.0 during the 7th day and compared to butterfly wing tea, the pH ranged between 3.8 and 3.2. Although using pH can be one of the easy ways to determine consumption time, by studying the titratable acidity for both samples, the optimum consumption time was found to be around the 5th day for black kombucha tea reaching 4.85g/L and after the 6th day for butterfly wing tea with 4.2g/L. Yeast counts for both samples were found to be experiencing a fluctuation between the 1st day and 7th day of fermentation with readings from 5.3 log cfu/ml to 6.5 log cfu/ml. The ethanol content for black tea was found to be extremely low with a value of 0.139%ABV but compared to butterfly wing kombucha tea, the contents of ethanol slightly surpassed that of the control with 0.151%ABV. The low ABV levels denote that acetic acid bacteria counts were equal or greater than yeast count to be able to convert much of ethanol produced by yeast to acetic acid. However, both of the samples are considered safe to be consumed since the ABV does not exceed the required ABV of 0.5% to be considered an alcoholic beverage.