# Enhancement of Wheat Flour and Dough Properties by Non-Thermal Plasma Treatment of Wheat Flour
## 3 Results and Discussion
### Effects of Non-Thermal Plasma-Treatment Reactor Filling on Wheat Flour and Dough Properties
#### 3.2.2 Visco-Elastic Properties of Dough  
Equivalent to the analysis shown in Figure 5 and Table 1, Figure 8 and Table 2 describe the influence of flour mass (i.e., reactor filling) on wheat dough visco-elastic properties. Independent of the treated flour quantity, the results demonstrate an increase in viscoelastic properties of doughs made with treated flour samples in comparison to doughs prepared with untreated wheat flour.  
Figure 7: Effects of reactor filling on the WHC (**a**) and WBC (**b**) values of untreated and NTP-treated flour (type 550; treatment time: 3 min).  
The experimental results demonstrate that when a too small (50 g) or a too large (450 g) amount of flour is placed inside the treatment reactor, the rheological properties of the formed dough are only mildly increased. G\({}^{\prime}\) and G\({}^{\prime\prime}\) reach their maximum values with  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Increase (\%)** & \multicolumn{2}{c}{**50 g**} & \multicolumn{2}{c}{**150 g**} & \multicolumn{2}{c}{**250 g**} & \multicolumn{2}{c}{**350 g**} & \multicolumn{2}{c}{**450 g**} \\ \hline
**Flour Type** & **G\({}^{\prime}\) (\%)** & **G\({}^{\prime\prime}\) (\%)** & **G\({}^{\prime}\) (\%)** & **G\({}^{\prime\prime}\) (\%)** & **G\({}^{\prime\prime}\) (\%)** & **G\({}^{\prime\prime}\) (\%)** & **G\({}^{\prime\prime}\) (\%)** & **G\({}^{\prime}\) (\%)** & **G\({}^{\prime}\) (\%)** \\ \hline
**550** & 85–130 & 76–111 & 155–203 & 114–158 & 119–172 & 94–141 & 119–184 & 91–150 & 115–183 & 93–159 \\ \hline
**1050** & 0–28 & 0–17 & 19–40 & 8–29 & 0–5 & 0–4 & 0–10 & 0–6 & 0–4 & 0–6 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Increase in the G\({}^{\prime}\) and G\({}^{\prime\prime}\) values of the doughs produced with plasma-treated flour samples (presented as minimum-to-maximum increase in comparison to doughs produced with untreated flour samples) as a function of reactor filling (i.e., flour mass).  
Figure 8: Change in the storage (G\({}^{\prime}\)) and loss (G\({}^{\prime\prime}\)) moduli of wheat dough as a function of NTP treatment at different reactor fillings (50, 150, 250, 350 and 450g, at 10 RPM): (**a**) type 550; (**b**) type 1050.  
a flour mass of 150 g and then slowly decline again. Such a limitation is not observed in the case of rheological property enhancement using chemicals, such as Vitamin C or ascorbic acid, L-Cysteine and Azodicarbonamide (ADA) [71; 72; 73]. A few milligrams of such chemicals (e.g., 10-20 mg of ADA) per kilogram of wheat flour is enough to improve wheat flour properties [74]. Similar to the findings in Figure 5, the results shown in Figure 8 also confirm the previous findings about the limited influence of NTP treatment on the properties of dough made with flour type 1050. This can be connected to the changes in WHC and WBC values shown in Figure 7. It has also been reported that chemical improvers, e.g., vitamin C, also generally improve the visco-elasticity of low-gluten flour as compared with high-gluten flour [75]. Statistical analysis again confirmed _p_-values less than 0.05 in the case of type 550 and greater than 0.05 in the case of type 1050.  
The presented results demonstrate the significance of flour particle-plasma species contact, which depends on the percentage of the reactor volume that is filled with flour. This factor can significantly limit the effect of NTP on flour functional properties. In order to achieve better effects of NTP treatment, the threshold for the reactor volume in this set-up is in a range of 6-13%.