## 3 Results
### Antioxidant Potential of Hydrogel Beads  
The formulated hydrogel beads were also tested for their antioxidant potential, which was evaluated by the most commonly used assays (CUPRAC, FRAP, ABTS, and DPPH assays). The results are presented in Table 3. As was determined for total polyphenols and proanthocyanidins, as well as for individual polyphenols, the composition of the encapsulation mixture played a major part in the antioxidant potential of hydrogel beads, which can primarily be linked to the concentration of phenolic compounds and their ability to act as antioxidants. Additionally, each method is characterized by its mechanism of action. The DPPH assay revealed that the antioxidant potential of chokeberry juice was 140.85 umol TE/100 g, while for alginate beads, it was 21.93 umol TE/100 g. Alginate/pullulan/sucrose and alginate/trehalose beads had slightly lower antioxidant potential than the control sample (21.2 umol TE/100 g), while other samples had higher antioxidant potential. For those beads, antioxidant potential decreased in the following order: alginate/sucrose > alginate/pullulan > alginate/pullulan/trehalose (38.54 umol TE/100 g > 30.19 umol TE/100 g > 26.87 umol TE/100 g). A slightly different trend was observed for ABTS results. The antioxidant potential of chokeberry juice was 145.85 umol TE/100 g. Alginate/trehalose and alginate/pullulan/sucrose beads had lower antioxidant potentials (17.39 umol TE/100 g and 21.5 umol TE/100 g, respectively) than the control sample (42.56 umol TE/100 g). Alginate/pullulan beads (86.99 umol TE/100 g) had considerably higher antioxidant potential than the control sample, while the antioxidant potentials of alginate/sucrose and alginate/pullulan/trehalose were 68.66 umol TE/100 g and 66.0 umol TE/100 g, respectively. Considering FRAP results, it was observed that alginate/trehalose and alginate/pullulan/sucrose beads had the lowest antioxidant potential (3.1 umol TE/100 g). Other samples had higher antioxidant potential than the control sample (3.83 umol TE/100 g). Alginate/pullulan and alginate/sucrose beads had the highest antioxidant potential (6.3 umol TE/100 g), while the antioxidant potential of alginate/pullulan/trehalose beads was 5.78 umol TE/100 g. Chokeberry juice had the highest antioxidant activity, at 15.39 umol TE/100 g. CUPRAC results also revealed that alginate/trehalose and alginate/pullulan/sucrose beads had lower antioxidant potentials (184.67 umol TE/100 g and 203.98 umol TE/100 g, respectively) than the control sample (261.44 umol TE/100 g). For the other hydrogel beads, antioxidant potential decreased in the following order: alginate/pullulan > alginate/sucrose > alginate/pullulan/trehalose (438.0 umol TE/100 g > 428.34 umol TE/100 g > 391.99 umol TE/100 g). For this method, as well as for the others, the highest antioxidant activity was determined for chokeberry juice, at 1052.01 umol TE/100 g. \begin{table}
\begin{tabular}{c c c c c} \hline
**Samples** & **FRAP** & **CUPRAC** & **DPPH** & **ABTS** \\ \hline CJ & 15.39 \(\pm\) 0.03 e & 1052.01 \(\pm\) 1.47 g & 140.85 \(\pm\) 0.78 f & 145.85 \(\pm\) 0.85 g \\ ALG\_CJ & 3.83 \(\pm\) 0.05 b & 261.44 \(\pm\) 1.23 c & 21.93 \(\pm\) 0.11 b & 42.56 \(\pm\) 0.21 c \\ ALG\_P\_CJ & 6.48 \(\pm\) 0.08 d & 438.00 \(\pm\) 1.93 f & 30.19 \(\pm\) 0.56 d & 86.99 \(\pm\) 0.07 f \\ ALG\_S\_CJ & 6.21 \(\pm\) 0.08 d & 428.34 \(\pm\) 1.68 e & 38.54 \(\pm\) 0.64 e & 68.66 \(\pm\) 0.77 e \\ ALG\_T\_CJ & 3.00 \(\pm\) 0.08 a & 184.67 \(\pm\) 1.29 a & 20.17 \(\pm\) 0.90 a & 17.39 \(\pm\) 0.48 a \\ ALG\_P\_S\_CJ & 3.19 \(\pm\) 0.10 a & 203.98 \(\pm\) 1.49 b & 20.31 \(\pm\) 0.95 a & 21.50 \(\pm\) 0.72 b \\ ALG\_P\_T\_CJ & 5.78 \(\pm\) 0.25 c & 391.99 \(\pm\) 1.48 d & 26.87 \(\pm\) 0.51 c & 66.00 \(\pm\) 0.23 d \\ \hline \end{tabular}
\end{table} 
Table 3: Antioxidant activity of chokeberry juice and hydrogel beads. The correlation between the investigated parameters was also assessed and is presented in Table 4. The correlation between total polyphenols and proanthocyanidins was very high (0.9996).