## 3 Results and Discussion
#### 3.3.4 Flavonoids, Total Phenols Content, Radical Scavenging Activity of Gluten Free Muffins (GFM)  
The total flavonoids content of GFM is illustrated in Figure 9. In the final baked muffins manufactured with SP 24 h, a total content of 1561 mg Qe/100 g f.w. was determined, compared with OR PF 24 h, where flavonoids had a total amount of 1317 mg Qe/100 g f.w. The difference between the samples could be explained by the presence of SP or OR 24 h sourdoughs. Nonetheless, it is noteworthy to mention that [96] identified in buckwheat flour a total of 188 flavonoid metabolites that could positively influence the content of flavonoids in the muffins. On the other side, the thermal treatment of the final baked goods could have a negative influence on the total flavonoids content [97]. The total phenols (TF) and radical scavenging activity (RSA%) of gluten free muffins made with SP sourdough were significantly different to those made with OR sourdough (Figure 10) due to the capacity of \(Lp\) to produce higher extent of lactic acid amount in SP sample, that could influence through acidification the extractability of total phenols and the antioxidant potential. Moreover, the interaction of Folin-Ciolcateu reagent with other non-phenolic compounds like vitamins, amino acids, and proteins could also have an influence on the number of polyphenic compounds. On the other side, the lower OR 24 h total phenols and radical scavenging activity suggested that spontaneous fermentation and quinone endogenous enzymes were not able to decrease the pH and release antioxidant compounds [98]. \begin{table}
\begin{tabular}{l c c c c c c c} \hline \hline
**Samples** & **Ca** & **Mg** & **K** & **Fe** & **Cu** & **Zn** & **Mn** \\ \hline OR PF 0 h & 8.21 \(\pm\) 0.03 \({}^{\rm{A}}\) & 147.16 \(\pm\) 0.07 \({}^{\rm{A}}\) & 411.67 \(\pm\) 0.03 \({}^{\rm{A}}\) & 0.99 \(\pm\) 0.02 \({}^{\rm{A}}\) & 0.40 \(\pm\) 0.05 \({}^{\rm{A}}\) & 0.90 \(\pm\) 0.23 \({}^{\rm{A}}\) & 0.89 \(\pm\) 0.02 \({}^{\rm{A}}\) \\ SP PF 0 h & 8.34 \(\pm\) 0.05 \({}^{\rm{A}}\) & 148.32 \(\pm\) 0.09 \({}^{\rm{A}}\) & 410.36 \(\pm\) 0.29 \({}^{\rm{A}}\) & 1.00 \(\pm\) 0.03 \({}^{\rm{A}}\) & 0.41 \(\pm\) 0.04 \({}^{\rm{A}}\) & 0.93 \(\pm\) 0.02 \({}^{\rm{A}}\) & 0.90 \(\pm\) 0.05 \({}^{\rm{A}}\) \\ OR PF 12 h & 10.30 \(\pm\) 0.02 \({}^{\rm{A}}\) & 151.00 \(\pm\) 0.07 \({}^{\rm{A}}\) & 420.69 \(\pm\) 0.34 \({}^{\rm{A}}\) & 1.03 \(\pm\) 0.05 \({}^{\rm{A}}\) & 0.41 \(\pm\) 0.01 \({}^{\rm{A}}\) & 1.09 \(\pm\) 0.05 \({}^{\rm{A}}\) & 0.99 \(\pm\) 0.04 \({}^{\rm{A}}\) \\ SP PF 12 h & 12.06 \(\pm\) 0.01 \({}^{\rm{A}}\) & 172.12 \(\pm\) 0.04 \({}^{\rm{B}}\) & 465.24 \(\pm\) 0.69 \({}^{\rm{B}}\) & 1.30 \(\pm\) 0.06 \({}^{\rm{A}}\) & 0.40 \(\pm\) 0.34 \({}^{\rm{A}}\) & 1.34 \(\pm\) 0.07 \({}^{\rm{A}}\) & 1.22 \(\pm\) 0.45 \({}^{\rm{A}}\) \\ OR PF 24 h & 11.20 \(\pm\) 0.30 \({}^{\rm{A}}\) & 159.81 \(\pm\) 0.02 \({}^{\rm{A}}\) & 430.95 \(\pm\) 0.72 \({}^{\rm{A}}\) & 1.09 \(\pm\) 0.03 \({}^{\rm{A}}\) & 0.45 \(\pm\) 0.21 \({}^{\rm{A}}\) & 1.20 \(\pm\) 0.11 \({}^{\rm{A}}\) & 1.12 \(\pm\) 0.34 \({}^{\rm{A}}\) \\ SP PF 24 h & 14.25 \(\pm\) 0.65 \({}^{\rm{B}}\) & 195.99 \(\pm\) 0.02 \({}^{\rm{B}}\) & 490.20 \(\pm\) 0.89 \({}^{\rm{B}}\) & 1.55 \(\pm\) 0.01 \({}^{\rm{B}}\) & 0.89 \(\pm\) 0.11 \({}^{\rm{B}}\) & 1.75 \(\pm\) 0.10 \({}^{\rm{B}}\) & 1.51 \(\pm\) 0.22 \({}^{\rm{B}}\) \\ \hline \hline \end{tabular}  
* The results are expressed in mg/100 g fresh weight (f.w.). Small letters in common indicate no significant differences between OR and SP samples withdrawn at different moments; Big different letters indicate significant differences between SP and OR samples withdrawn at the same moment.  
\end{table} 
Table 6: Mineral content of SP PF and OR PF muffins. It is important to mention that the TF amount of quinoa flour and RSA were 451 \(\pm\) 0.3 mg GAE/100 g f.w. and 92 \(\pm\) 0.5%, respectively [38].