## 3 Results
### Phenolic Content in Wafers  
The content of total phenolic compounds and groups of polyphenols in extracts prepared from the control and fortified wafers is shown in Figure 3a-d. In all ethanol extracts (E) from wafers with the addition of raspberry juice, the total phenolic compound content was higher than in the control sample. The content of phenolic compounds increased proportionally with the increase in the raspberry juice addition (Figure 3a); \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & & & & & & \\ \hline
**Sample** & \(L^{*}\) & \(a^{*}\) & \(b^{*}\) & \(C^{*}\) & \(h^{\circ}\) & \(\Delta\mathbf{E}\) \\ \hline CW & 84.95 \(\pm\) 1.06 d & 5.49 \(\pm\) 0.08 a & 29.59 \(\pm\) 0.32 e & 30.09 \(\pm\) 0.33 e & 1.39 \(\pm\) 0.00 d & - \\ RJ10 & 78.37 \(\pm\) 1.20 c & 5.26 \(\pm\) 0.26 a & 21.54 \(\pm\) 0.37 d & 22.17 \(\pm\) 0.43 d & 1.33 \(\pm\) 0.01 d & 9.76 \(\pm\) 0.13 a \\ RJ20 & 76.94 \(\pm\) 0.42 c & 6.83 \(\pm\) 0.13 a & 14.69 \(\pm\) 0.46 c & 16.23 \(\pm\) 0.40 b & 1.13 \(\pm\) 0.00 c & 16.85 \(\pm\) 0.17 b \\ RJ50 & 72.20 \(\pm\) 0.33 b & 10.13 \(\pm\) 0.21 b & 9.54 \(\pm\) 0.47 b & 13.91 \(\pm\) 0.47 a & 0.76 \(\pm\) 0.01 b & 24.21 \(\pm\) 0.29 c \\ RJ75 & 71.69 \(\pm\) 0.76 b & 10.96 \(\pm\) 0.09 b & 9.66 \(\pm\) 0.61 b & 14.66 \(\pm\) 0.47 ab & 0.72 \(\pm\) 0.023 b & 24.57 \(\pm\) 0.07 c \\ RJ100 & 62.50 \(\pm\) 0.64 a & 19.28 \(\pm\) 0.84 c & 2.67 \(\pm\) 0.86 a & 19.47 \(\pm\) 0.95 c & 0.14 \(\pm\) 0.04 a & 37.99 \(\pm\) 0.69 d \\ \hline \hline \end{tabular}  
* \(L^{*}\) for lightness from black (0) to white (100), \(a^{*}\) from green (\(-\)) to red (\(+\)), and \(b^{*}\) from blue (\(-\)) to yellow (\(+\)), C*—chroma, \(h^{\circ}\)——tube angle, \(\Delta E\)—total color differences. CW—control wafers, RJ10–RJ100—wafers with 10% to 100% raspberry juice addition, respectively. All values are mean \(\pm\) standard deviation for triplicate experiments. Means in the rows marked with the same letters do not differ significantly at \(p\leq 0.05\).  
\end{table} 
Table 3: Assessment of wafer color parameters. however, the difference was not statistically significant in the case of the RJ10 sample. The highest amount of the tested compounds was determined in the RJ100 sample. The content of total phenolic compounds was higher in all PBS extracts (B) from wafers with the addition of raspberry juice than in the control sample. It was between 0.32 mg/g in the control sample and 1.11 mg/g in the RJ100 sample. The content of these compounds increased in direct proportion to the juice concentration in the tested wafers (Figure 3a). The content of total phenolic compounds after in vitro digestion also increased with the increase in the amount of raspberry juice in the wafers. A statistically significant increase vs. the control was observed in the RJ20 samples (Figure 3a). The comparison of the total phenolic compound content between the three extracts from the tested wafers (E, B, and D) showed significant differences. The content of phenolic compounds in the PBS extracts was lower than in the ethanol extracts, which can be explained by the fact that ethanol is a much better solvent for phenolic compounds. In turn, extracts subjected to simulated digestion had significantly higher values than the ethanol and PBS extracts. The extraction method may affect the content of phenolic compounds and their antioxidant activity. For this reason, we tested three types of extracts: ethanolic (E) (i.e., chemical), buffer (B), and simulated digestion (D). Chemical extraction is most often used to determine  
Figure 3: Phenolic compound content in the different extracts from the control and fortified wafers. (**a**) Total phenolic content; (**b**) flavonoid content; (**c**) phenolic acid content; (**d**) anthocyanin content. E—ethanolic extract; B—buffer extract; D—extract after in vitro digestion. CW—control wafers, RJ10–RJ100—wafers with raspberry juice addition (from 10% to 100% water substitution, respectively). All values are mean \(\pm\) standard deviation for triplicate experiments.