## 3 Results and Discussion
### Rheological Characterization  
Dynamic rheological tests (frequency sweep experiments), at 15 and 25 \({}^{\circ}\)C, respectively, were carried out to study the dough samples. Macroscopically, one usually observes a liquid structure for the samples. Strain-sweep experiments that are not reported here revealed that all samples have a nonlinear response at a considerably higher strain. The dynamic moduli for all samples lose linearity at ca. 100% strain at a frequency of 1 Hz. The mechanical spectrum reflects the texture structure of the system. In Figure 5, the rheological spectra were reported for all samples. It is worthy to note differences in G* (Figure 5) where all values are higher than those of muffin dough without baking (WY). It is also important to note that MUC and TAR samples show similar rheological behaviour. Their frequency profiles are higher than those of other ones. These results indicate that the synthesized baking affects the structures of the system and improve the mechanical properties of the doughs. The variation of viscosity versus time at different shear rates for samples was measured (Figure 5). It was observed that different samples have different rheological behaviors. A thinning behavior is shown, where the viscosity is dependent on shear rates. Higher shear rates reduce the viscosity such as in a shear-thinning fluid, also known as a pseudo plastic system. The shear thinning behavior appears increasingly pronounced when tartaric is used. The pseudo plastic fluid and higher viscosity can be attributed to higher structure-forming interactions [(45; 46)]. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Baking**} & **TPC** & **TAC** & \multicolumn{2}{c}{**IC\({}_{50}\) (mg mL\({}^{-1}\))**} \\ \cline{3-5}  & **(meq CT/g Baking)** & **(meq CT/g Baking)** & **DPPH Radical** & **ABTS Radical** \\ \hline T\_BP & 0.0298 \(\pm\) 0.021 b  & 0.0081 \(\pm\) 0.0009 b  & 2.358 \(\pm\) 0.076 a  & 0.149 \(\pm\) 0.011 a  \\ M\_BP & 0.0530 \(\pm\) 0.035 a  & 0.0119 \(\pm\) 0.0011 a  & 0.518 \(\pm\) 0.015 b  & 0.112 \(\pm\) 0.010 b  \\ C\_BP & - & - & - & - \\ \hline Positive control & \(0.1086\pm 0.0124\) & \(4.785\pm 0.126\) & \(1.654\pm 0.099\) \\ Ascorbic acid & & & & \\ \hline TPC = Total Phenolic Content; TAC = Total Antioxidant Capacity; CT = Catechin; DPPH = 2,2\({}^{\prime}\)-difenyl-1-picrylidrazil; & & & \\ ABTS = 2,2\({}^{\prime}\)-azino-bis (3-etylbenzodiazep-6-sulphonic)M\_BP = (+)-catechin\_mucic acid-based baking powder; & & & \\ T\_BP = (+)-catechin\_tartaric acid-based baking powder; C\_BP = commercial baking powder. (-) = not detected. & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Antioxidant performances of baking powders. Data are presented asmean \(\pm\) SD (\(n=3\)), different letters in the same columns are statistically different (\(p<0.05\)). In Figure 6, the frequency sweep tests of baked muffins achieved employing the synthetic baking (M_MUF and T_MUF) and commercial one (C_MUF) are reported. It is worthy to note the effects of different baking on the rheological properties of the final products. The trends are almost flat in frequency (the structure is formed by large network thus a high coordination number); additionally, the higher values as a function of the frequency observed for T_MUF and M_MUF can be related to the higher \"interaction strength\" between the rheological units (stronger links). This means that the synthetic baking ingredients (M_MUF and T_MUF) form more structured samples [47]. Similar trends are observable between them, while they are different in comparison with the C_MUF sample (Figure 7). Figure 5: Frequency Sweep Test muffin dough (G *). (a): 15 °C, (b): 25 °C. MD = muffin dough without baking; T_MD = muffin dough with T_BP; M_MD = muffin dough with M_BP; C_MD = muffin dough with C_BP. Figure 6: Step Rate muffin dough at 15 °C. MD = muffin dough without baking; T_MD = muffin dough with T_BP; M_MD = muffin dough with M_BP; C_MD = muffin dough with C_BP. Figure 7: Frequency Sweep Test at 25 °C muffin.