However, the quinic acid concentration in the fermented green coffee beans was not by the decrease in the chlorogenic acid concentration following fermentation.
The decrease in the latter’s concentration would likely be attributed to hydrolysis catalyzed by chlorogenic acid esterase, whose activity had been reported in other fungal species such as Aspergillus spp. (Asther et al., 2005).
It is plausible that the metabolism of quinic acid by R. oligosporus could have cancelled out the increase in concentration brought about by chlorogenic acid hydrolysis.