Withdrawal of stimulants from tea infusion by SCOBY during kombucha fermentation: A biochemical investigation

Caffeine content in kombucha is very much lower than that of normal tea infusion. Though this stimulant plays an important role in kombucha fermentation as it regulates the starter or SCOBY (symbiotic colony of bacteria and yeasts) to produce the cellulose network on broth to accelerate the fermentation process. This research was designed to investigate the aftermath of caffeine and related tea alkaloids in kombucha through preliminary biochemical tests and chromatographic analysis where both the broth (beverage) and SCOBY (the cellulose layer) were taken as individual samples. The beverage clearly revealed negative in all the tests where the SCOBY extract showed richness in alkaloid content. Moreover, GC-MS analysis revealed presence of caffeine (8.7%); guanosine (12.01%), the precursor of caffeine; thymine (4.08%); and some undesirable components which has confirmed that SCOBY has an ability to capture a huge amount of stimulants from tea during fermentation.