# Impact of Ferment Processing Parameters on the Quality of White Pan Bread
## 3 Results and Discussion
### Fermentation Time  
#### 3.3.1 Effect of Fermentation Time on Ferment Quality  
The effect of fermentation time on TTA levels during the fermentation cycle and after storage at 24 and 48 h is shown in Figure 6. Regardless of the fermentation time, all ferrents had the highest TTA levels within 90 or 100 min of fermentation and then showed a steady decline after 100 min of fermentation. Overall, longer fermentation times (210 and 280 min) resulted in lower TTA levels by the end of the fermentation cycle. This is likely due to the accumulation of alcohol in the liquid phase of the ferment which may inhibit yeast activity [5]. The TTA level of the ferment that was fermented for 90 min did not change significantly between 50 min and 90 min or after 24 or 48 h of storage. This may indicate that fermentation was halted at the peak of baker's yeast activity. For the ferment that was fermented for 210 min there was a significant reduction in TTA levels at 134 min of fermentation which continued to decrease as fermentation time increased reaching a TTA value of 14.3 mL by the end of the fermentation stage. [PERSON] et al. observed that ferments containing 40% and 50% flour reached their highest TTA level after 135 min of fermentation and then decreased for the reminder of the fermentation period [17]. The ferment that was fermented for 280 min was monitored for TTA with shorter time intervals between 210 and 280 min to try and identify the time when the ferment had reached a constant level of acid accumulation and could be considered as a mature ferment indicating a completion of fermentation. Changes in TTA for the ferment that was fermented for 280 min followed the same trend as the fermentents fermented for a shorter period of time. After 100 min of fermentation, there was a steady decline in TTA levels with the lowest TTA level of 13.6 mL found for the sample of ferment tested at 240 min. The reduction in TTA levels was likely due to the generation of alcohol and its inhibiting impact on yeast activity [5]. Between 225 and 280 min of fermentation, TTA levels did not change significantly indicating that the acid development was constant during this time. Based on the TTA results a fermentation time of 240 min was determined as the optimal fermentation time as the TTA levels remained constant. During storage, all ferments that were fermented for the four fermentation times demonstrated a sharp increase in TTA when stored for 24 h, which might be due to formation of carbonic acid from carbon dioxide and water and initiation of spontaneous fermentation by natural  
Figure 6: Changes in total tittatable acidity of the ferment during fermentation and over a 48 h storage. Bars represent the means and standard deviations of two replication. Bars with different letters indicate significant differences for the results for each fermentation time at \(p<0.05\) (Tukey–Kramer test). Results for 280 min of fermentation at 48 h of storage are not available. microorganisms that are present on flour and yeast [24]. The TTA level appeared to remain constant since the TTA levels after 48 h of storage were not significantly different from those observed at the maximum acid accumulation during 90 and 100 min of fermentation and at 24 h of storage indicating that the ferment retained its fermentation rate during storage. The pH of the ferments ranged from 5.5 to 5.3 during preparation and storage regardless of the fermentation time (results not shown). Changes in the viscosity of the ferment that was fermented for different fermentation times and measured at 8 and 9 min holding time of the pasting profile are shown in Figure 7.  
Regardless of the length of fermentation, there were no differences in viscosity observed among the ferments measured at 8 and 9 min of holding time indicating that fermentation time did not significantly impact viscosity.