## 3 Results and Discussion
### Characteristics of Freeze-Dried Red Potato Pulp and Cherry Pomace
At the same time, it was found that the increase in fiber fractions, as well as total fiber, was proportional to the amount of added pomace and potato, and the largest increase was observed at the 30% addition level of the above-mentioned components in pasta. In the research of [PERSON] et al. (2010) [35] concerning the influence of powdered mango skin on the contents of dietary fiber fractions and increase in their level was between 24% \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & \multicolumn{2}{c}{**Dietary Fiber**} & \multicolumn{2}{c}{**Polyphenols**} \\ \hline  & **Soluble** & **Insoluble** & **Total** & \\ \hline Control & 1.72 \(\pm\) 0.03 a \({}^{\dagger}\) & 0.84 \(\pm\) 0.06 a & 2.56 \(\pm\) 0.03 a & 57 \(\pm\) 14 a \\ RPP-10 & 2.21 \(\pm\) 0.02 b & 1.12 \(\pm\) 0.01 b & 3.33 \(\pm\) 0.01 b & 104 \(\pm\) 1 b \\ RPP-20 & 2.75 \(\pm\) 0.04 c & 1.51 \(\pm\) 0.04 c & 4.26 \(\pm\) 0.08 c & 152 \(\pm\) 6 c \\ RPP-30 & 2.95 \(\pm\) 0.04 d & 1.67 \(\pm\) 0.02 d & 4.62 \(\pm\) 0.02 d & 234 \(\pm\) 2 e \\ CP-10 & 3.69 \(\pm\) 0.02 e & 2.09 \(\pm\) 0.01 e & 5.78 \(\pm\) 0.01 e & 146 \(\pm\) 1 c \\ CP-20 & 4.29 \(\pm\)0.04 f & 2.81 \(\pm\) 0.08 f & 7.70 \(\pm\) 0.04 f & 178 \(\pm\) 5 d \\ CP-30 & 6.84 \(\pm\) 0.04 g & 3.97 \(\pm\) 0.04 g & 10.82 \(\pm\) 0.07 g & 275 \(\pm\) 0.03 f \\ \hline \hline \end{tabular} \({}^{\dagger}\) Different letters in columns indicate significant differences between individual samples (\(p\leq 0.05\)); data are presented as the mean \(\pm\) SD.  
\end{table} 
Table 4: Dietary fiber fractions (g/100 g DM) and polyphenols (mg catechin equivalent/100 g DM) in pasta samples. and 57% (soluble fraction), 87% and 144% (insoluble fraction) and 61% and 107% (total fiber) in pasta containing the above-mentioned additive in comparison to the control. According to [PERSON] et al. [36], in which pasta was enriched with chia seeds (2.5% to 10% addition level), an increasing tendency in the total dietary fiber (from 58% to 217%) could also be observed. Also, [PERSON] et al. [37] noticed that date, apple and pear by-products as functional ingredients of pasta lead to a rise in the fiber level parallel to the level of their addition (2.5-10%); the observed effects ranged between 30 and 325% in comparison to the control pasta. The pastas enriched with tomato by-products were characterized by an elevated level of the soluble fiber fraction (22 to 43%) and insoluble one (35 to 59%), corresponding to the 31 to 54% change in total fiber in comparison to the control [38]. [PERSON] et al. [33] showed that the enrichment of pasta with orange by-product fiber could result in an augmentation of the soluble dietary fiber level between 19 and 43%, while the respective change in the insoluble fraction could even be threefold, which corresponds to the increase in total fiber up to two times in comparison to the control. The increase in total dietary fiber reported by [PERSON] et al. [34] after using _Hibiscus sabdarifa_ by-product (10-20%) to enhance the nutritional quality of pasta was even ninefold in the case of the soluble fraction, while the levels of total and insoluble fiber were approximately double those found for the control when 20% of addition was applied in the pasta formulation. In the study of [PERSON] and [PERSON] [14] on the effect of using carrot pomace and beetroot-apple pomace on dietary fiber in pasta, the highest applied of the additives (30%) resulted in the largest increase of soluble, insoluble and total fibers (3.5-fold, 2.5-fold and 3-fold, respectively) in comparison to the control. All the above-mentioned authors [14; 33; 34; 35; 36; 37; 38] showed that the content of the soluble and insoluble fiber fractions, as well as total dietary fiber, increased successively with the increase in the level of the applied addition, which was also noted in this work (Table 4). Similar patterns could be found referring to the nutrient content of pasta enriched with various by-products.