# Impact of Ferment Processing Parameters on the Quality of White Pan Bread
## 3 Results and Discussion
### Ferment Storage Time  
#### 3.2.1 Effect of Storage Time on Ferment Quality  
The ferment was evaluated for TTA and viscosity during the fermentation cycle and during storage of the ferment. Measuring of TTA is commonly used by the baking industry to monitor the rate of dough fermentation [15]. During fermentation, TTA level remained at 22.0 mL and then decreased significantly to 17.1 mL by the end of the 150 min fermentation stage (Figure 1). \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter 1** & **Value** \\ \hline Protein (\%) & 11.6 \\ Moisture (\%) & 14.8 \\ Ash (\%) & 0.63 \\ Falling number (sec) & 405 \\ Starch damage (UCD) & 25.1 \\ Farinograph Properties & \\ Absorption (\%) & 62.7 \\ Dough development time (min) & 2.1 \\ Stability (min) & 15.0 \\ Mixing tolerance index (BU) & 14 \\ RVA Pasting Properties & \\ Peak viscosity (RVU) & 160 \\ Hot paste viscosity (RVU) & 88 \\ Breakdown (RVU) & 72 \\ Final viscosity (RVU) & 177 \\ Setback (RVU) & 89 \\ Pasting time (min) & 5.98 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Flour quality parameters. Figure 1: Changes in total titratable acidity of the ferment during fermentation and over storage time. Bars represent the means and standard deviations of two replication. Bars with different letters indicate significant differences for the results at \(p\) < 0.05 (Tukey–Kramer test). During storage, TTA increased but this was not significantly different from the TTA levels observed during the fermentation stage. This suggested that ferment can be stored up to 72 h and still maintain the same rate of fermentation. [PERSON] reported that mature ferment upon completion of fermentation and conditioning can be used for dough mixing right after preparation or stored for 48 h or longer and maintain its fermentative vitality at 10 \({}^{\circ}\)C [11]. It has also been reported that baker's yeast requires approximately 45 min to fully adapt to fermentation in a favourable environment [23]. Changes in the TTA of the ferment suggest that fermentation, initiated by baker's yeast, reached a maximum rate at 50 min of fermentation which was maintained until 100 min. After 100 min of fermentation, TTA decreased likely due to an accumulation of alcohol in the liquid phase of the ferment, a by-product of yeast fermentation that may inhibit yeast activity [5]. Carbon dioxide, which is also a product of fermentation, dissolves to form bicarbonate ions, which acidity the dough. This may explain why TTA increased after 24 h of storage. Another possible explanation of the increase in TTA during storage might be initiation of spontaneous fermentation and production of acids as flour has a large population of natural microorganisms [24]. The pH of the ferment ranged from 5.5 to 5.3 during fermentation and over storage (results not shown). Both TTA and pH provide an indication of acid development in the ferment. However, pH measures a concentration of hydrogen ions which are produced by dissociation of acids depending on strength of the acid, whereas TTA measures the total amount of acid in a system [15]. Less drastic changes in pH compared to TTA is likely due to absorption of hydrogen ions in the ferment by the weak basic groups of proteins and their buffering effect [25]. A comparison of the RVA pasting curves of the ferment after 150 min of fermentation with wheat flour is shown in Figure 2a,b, respectively. Although a direct comparison between the ferment and wheat flour cannot be made due to differences in the ingredients, preparation of the slurries, and the pasting profiles used, some general observations can be made. The pasting curve of the ferment showed an increase in viscosity during the heating cycle after which the viscosity plateaued as the cooling cycle started (Figure 2a), whereas the pasting curve of the wheat flour demonstrated a characteristic peak viscosity during the heating cycle as well as an increase in final viscosity upon cooling (Figure 2b).