## 3 Results and Discussion
### Characteristics of Obtained Preparations
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{Sample name} & \multicolumn{4}{c}{Chemical Composition} \\ \cline{2-6}  & Protein & Fat & Starch & Ash & Carbohydrates \\ \hline  & & & (g/100 g DM) & & \\ \hline E0 PP & 0.28\({}^{\text{c}}\)\(\pm\) 0.03 & 0.39\({}^{\text{c}}\)\(\pm\) 0.01 & 89.27\({}^{\text{a}}\)\(\pm\) 0.08 & 0.12\({}^{\text{a}}\)\(\pm\) 0.00 & 10.44 \({}^{\text{a}}\)\(\pm\) 0.02 \\ \hline E30 PP & 2.81\({}^{\text{b}}\)\(\pm\) 0.00 & 0.45\({}^{\text{b}}\)\(\pm\) 0.00 & 75.74\({}^{\text{b}}\)\(\pm\) 0.15 & 1.95\({}^{\text{b}}\)\(\pm\) 0.00 & 8.55\({}^{\text{b}}\)\(\pm\) 0.02 \\ \hline E40 PP & 3.64\({}^{\text{a}}\)\(\pm\) 0.04 & 0.52\({}^{\text{a}}\)\(\pm\) 0.01 & 73.66\({}^{\text{c}}\)\(\pm\) 0.08 & 2.35\({}^{\text{c}}\)\(\pm\) 0.00 & 5.67\({}^{\text{c}}\)\(\pm\) 0.02 \\ \hline  & & & Dietary fiber & & \\ \hline  & Soluble fraction & Insoluble fraction & Total & \\  & & (g/100 g DM) & & & \\ \hline E0 PP & 0.02\({}^{\text{c}}\)\(\pm\) 0.02 & 0\({}^{\text{c}}\)\(\pm\) 0 & 0.02\({}^{\text{c}}\)\(\pm\) 0.02 & \\ \hline E30 PP & 1.09\({}^{\text{b}}\)\(\pm\) 0.05 & 0.70\({}^{\text{b}}\)\(\pm\) 0.04 & 1.79\({}^{\text{b}}\)\(\pm\) 0.01 & \\ \hline E40 PP & 1.21\({}^{\text{a}}\)\(\pm\) 0.02 & 1.14\({}^{\text{a}}\)\(\pm\) 0.03 & 2.35\({}^{\text{a}}\)\(\pm\) 0.05 & \\ \hline  & Total phenolic content—with F-C & Total phenolic content—without F-C & ABTS (mMTx/kg DM) \\  & (mg catechin/100 g DM) & (mg catechin/100 g DM) & ABTS (mMTx/kg DM) \\ \hline E0 PP & 73.95\({}^{\text{c}}\)\(\pm\) 0.54 & 8.58\({}^{\text{c}}\)\(\pm\) 0.43 & 13.67\({}^{\text{c}}\)\(\pm\) 0.02 & \\ \hline E30 PP & 905.98\({}^{\text{b}}\)\(\pm\) 1.6 & 651.26\({}^{\text{b}}\)\(\pm\) 2.02 & 70.48\({}^{\text{b}}\)\(\pm\) 0.67 & \\ \hline E40 PP & 1135.69\({}^{\text{a}}\)\(\pm\) 1.63 & 807.93\({}^{\text{a}}\)\(\pm\) 1.26 & 78.33\({}^{\text{a}}\)\(\pm\) 0.41 & \\ \hline  & & & The other phenolic compounds & \\ \hline  & Phenolic acids (mg gallic & Flavonols & Anthocyanins & Flavonoids & \\  & acid/100 g DM) & (mg quercetin/100 g DM) & (mg cyanidin-3-glucoside/100 g DM) & (mg rutin/100 g DM) \\ \hline E0 PP & 0.00\({}^{\text{c}}\)\(\pm\) 0.00 & 0.00\({}^{\text{c}}\)\(\pm\) 0.00 & 0.00\({}^{\text{c}}\)\(\pm\) 0.00 & 1.22\({}^{\text{c}}\)\(\pm\) 0.07 & \\ \hline E30 PP & 89.50\({}^{\text{b}}\)\(\pm\) 2.82 & 31.31\({}^{\text{b}}\)\(\pm\) 1.74 & 2.64\({}^{\text{b}}\)\(\pm\) 0.06 & 266.44\({}^{\text{b}}\)\(\pm\) 0.91 & \\ \hline E40 PP & 116.6\({}^{\text{a}}\)\(\pm\) 6.40 & 45.93\({}^{\text{a}}\)\(\pm\) 2.00 & 4.10\({}^{\text{a}}\)\(\pm\) 0.01 & 358.56\({}^{\text{a}}\)\(\pm\) 1.03 & \\ \hline  & & & The data are expressed as the mean \(\pm\) standard deviation, with a minimum sample size of 2 (values denoted by the same letters in respective columns and within the analyzed parameter do not show statistically significant differences at the 0.05 level). & & \\ \end{tabular}
\end{table} 
Table 2: Basic chemical characteristics of obtained preparations. valuable metric for establishing a correlation between the content of phenolic compounds and their antioxidant activity. The amount of flavonoids in EOPP was small, but increased significantly with the proportion of red potato pulp. In the case of EOPP, no phenolic acids, flavonoids, or anthocyanins were found due to the lack of a bioactive component, i.e., red potato pulp. The E40 PP preparation was characterized by a higher content of phenolic acids, flavonoids, and anthocyanins by 30, 46, and 55%, respectively, compared to the E30 PP preparation (Table 2). The presence of these compounds results in very high antioxidant activity of these preparations, which is 5.3 times greater than that of the preparation made without potato pulp, i.e., EOPP (Table 2), which was confirmed by a strong correlation between TPC and ABTS (r = 0.995). Characterization of Sourdough, Dough, and Bread with the Participation of the Tested Preparations in Terms of Changes in Acidity  
Proper preparation of the sourdough affects the final quality of baking bread.