Figure 6.

The changes of contents of main phenolic compounds and caffeine of kombucha produced by fermentation with or without black tea residue at different fermentation stages. (a–h) kombucha from black tea, and (i–r) kombucha from green tea. Different letters illustrate significant differences (p < 0.05) for the same kombucha beverage at different fermentation times, and the same letter represents no significant difference (p > 0.05). Different colors of letters represent different kombucha fermentation with tea residue or without tea residue. * Indicates significant difference (p < 0.05) between kombucha fermentation with tea residue and kombucha fermentation without tea residue at the same fermentation time.