# 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 Time on Wheat Flour and Dough Properties
#### 3.1.2 Visco-Elastic Properties of Dough

Table 1: Increase in \(G^{\prime}\) and \(G^{\prime\prime}\) for the doughs produced with NTP-treated flour samples (presented as minimum-to-maximum increase) in comparison to doughs produced with untreated flour samples) as a function of treatment time. Figure 5: Change in the storage (G\({}^{\prime}\)) and loss (G\({}^{\prime\prime}\)) moduli of wheat dough as a function of NTP treatment time: (**a**) for the flour type 550; (**b**) for the flour type 1050. Analysis of variance (ANOVA) [59] was used in order to determine significant statistical differences between the samples. The obtained results for the type 550 flour (\(p<0.05\)) (provided in the Supplementary Materials S1) confirmed the existence of significant statistical differences between untreated and treated samples, i.e., the effect of non-thermal plasma treatment on flour properties was statistically significant. However, in the case of type 1050, the obtained \(p\)-value was larger than 0.05. This implies that the effect of NTP treatment on type 1050 flour was not statistically significant, i.e., the influence of treatment cannot be established. A general trend towards an increase in the yield points of the doughs produced with plasma-treated flour samples can be noticed, representing an increase in the linear visco-elastic (LVE) region. Increased elastic properties further indicate an increase in dough strength. The results presented in Figure 5a demonstrate that the flow point value increased by 51% and the yield point value by 75% when the flour type 550 was treated for 3 min in comparison to the untreated (control) sample. [PERSON] et al. [60] explained an increase in dough strength in terms of an increase in the number of disulphide bonds within the protein matrix in the dough, i.e., the higher the number of disulphide bonds, the higher the storage and loss moduli. The properties of the dough made from flour type 1050 (Figure 5b) showed similar qualitative behaviors under the same plasma conditions; however, the quantitative change was much lower than for that made with type 550 flour. Some other authors ([61; 62; 53]) have suggested that change in visco-elastic behavior could be connected to the hydration properties of wheat flour. The changes in moisture content, WHC and WBC, as shown in Figures 3 and 4, reflect the change in bonded and free water content levels, which directly affect gluten-starch and starch-starch bonding through hydrogen bonds. These bindings, enhanced by the plasma treatment, started to dominate the dough characteristics, making the treated samples stronger than the control samples. Based on the presented results, it can be concluded that a plasma treatment time of 5 min will result in decreased structural strength of wheat dough, which could be connected to the weakening of disulphide bonds in the protein matrix and to the decrease in the WHC and WBC of wheat flour. Further, it can be concluded that NTP-induced intensification of visco-elastic properties is inversely proportional to the amount of protein present in the flour, i.e., with a higher protein content, the change in the visco-elastic properties of dough due to NTP is lower.