3.2. Acrylamide reduction
Fig. 2 shows acrylamide degradation during fermentation. The instant coffee sample used to prepare the fermentation media was found to contain 1020 ìg/kg of acrylamide. The initial concentration of acrylamide in the fermentationmediawas 204 ìg/L. Similar to HMF, acrylamide concentration also showed an exponential decay during the fermentation process. The first order degradation kinetic model fitting parameters are given in Table 2. The rate of acrylamide degradation
was dependent on sucrose concentration in the fermentation medium. In the presence of 1% yeast inoculum, the degradation of acrylamide occurred 2.5 and 3.5 times faster in the samples containing 5% and 10% sucrose, respectively than in the samples containing 1% sucrose (p b 0.05). Similarly, in the fermentation process performed with 2% yeast inocula, acrylamide degradation occurred faster with the increasing amount of sucrose (p b 0.05).