## 3 Results and Discussions
### In Vitro Digestion  
To assess the release of nutrients, the cereal bar used as the model variant was enriched with freeze-dried _Aronia melanocarpa_ by-product powder before and after the digestion process, and the plain freeze-dried powder was subjected to an in vitro digestion process. The quantity of phenolic compounds and anthocyanins in the samples is presented in Table 4. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Peak** & **Rt (min)** & **Compound** & \begin{tabular}{c} **Control Bar +** \\ **Aronia before** \\ **Digestion** \\ \end{tabular} & \begin{tabular}{c} **Control Bar after** \\ **Digestion** \\ \end{tabular} & \
\begin{tabular}{c} **Control Bar +** \\ **Aronia Powder** \\ **after Digestion** \\ \end{tabular} &
\begin{tabular}{c} **Aronia Powder** \\ **after Digestion** \\ \end{tabular} \\ \hline
1 & 3.04 & Hydroxybenzoic acid & 223.58 \(\pm\) 0.38 & 335.99 \(\pm\) 0.78 N.S. & 3592.40 \(\pm\) 1.21 ** & 11,381.54 \(\pm\) 4.27 * \\
2 & 3.63 & Dihydroxybenzoic acid & n.d. & 259.86 \(\pm\) 0.52 N.S. & 2828.27 \(\pm\) 1.08 ** & 7125.05 \(\pm\) 3.08 * \\
3 & 9.65 & Protocatechuric acid & 315.68 \(\pm\) 0.41 & 482.72 \(\pm\) 0.69 N.S. & 3505.16 \(\pm\) 1.57 ** & 11,548.09 \(\pm\) 3.49 * \\
4 & 10.32 & Cyanidin glucoside & 253.42 \(\pm\) 0.30 & n.d. & 74.62 \(\pm\) 0.18 ** & 5197.59 \(\pm\) 1.36 * \\
5 & 11.29 & Cyanidin-glucose & 101.53 \(\pm\) 0.44 & n.d. & 71.99 \(\pm\) 0.24 ** & 2696.02 \(\pm\) 1.07 * \\
6 & 13.05 & Cyanidin & 29.49 \(\pm\) 0.20 & n.d. & n.d. & 124.19 \(\pm\) 0.19 * \\
7 & 13.35 & Caffe acid & 40.69 \(\pm\) 0.17 & 37.03 \(\pm\) 0.20 N.S. & 88.39 \(\pm\) 0.32 ** & 1395.14 \(\pm\) 1.01 * \\
8 & 14.48 & Kaempfer diglucoside & 30.96 \(\pm\) 0.15 & n.d. & 40.49 \(\pm\) 0.21 ** & 543.21 \(\pm\) 0.78 * \\
9 & 14.88 & Quercetin-acetyl- & 37.31 \(\pm\) 0.21 & n.d. & 38.01 \(\pm\) 0.17 ** & 681.32 \(\pm\) 0.86 * \\
10 & 15.61 & Quercetin rutinoside (Rutin) & 30.96 \(\pm\) 0.18 & n.d. & 32.07 \(\pm\) 0.14 ** & 624.89 \(\pm\) 0.73 * \\
11 & 16.17 & Quercetin glucoside & 34.84 \(\pm\) 0.14 & n.d. & 65.73 \(\pm\) 0.29 ** & 540.24 \(\pm\) 0.66 * \\
12 & 18.75 & Kaempfer glucoside & 42.25 \(\pm\) 0.22 & n.d. & n.d. & 168.98 \(\pm\) 0.31 * \\ \hline \hline \end{tabular}
\end{table} 
Table 4: The quantity of phenolic and anthocyanin compounds in aronia by-product bar samples and an aronia bar before and after in vitro digestion (\(\mu\)g/g). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Peak** & **Rt (min)** & \
\begin{tabular}{c} **UV** \\ **\(\Delta\)max** \\ **(nm)** \\ \end{tabular} &
\begin{tabular}{c} **[M + H]\({}^{+}\)** \\ **(\(ml/z\))** \\ \end{tabular} & **Compounds** & **Fresh Aronia B** & **Freeze-Dried Aronia B** \\ \hline
7 & 14.88 & 360, 255 & 611 & Quercetin-acetyl rhamno & 331.80 \(\pm\) 0.20 & 1068.519 \(\pm\) 0.31 *** \\
8 & 15.61 & 360, 255 & 491 & Quercetin-rutinoside (Rutin) & 383.25 \(\pm\) 0.33 & 1265.660 \(\pm\) 0.41 *** \\
9 & 16.17 & 360, 255 & 611 & Quercetin glucoside & 581.29 \(\pm\) 0.52 & 1700.039 \(\pm\) 0.56 *** \\
10 & 18.75 & 356, 256 & 465 & Kaempfer glucoside & 272.54 \(\pm\) 0.12 & 1269.002 \(\pm\) 0.18 *** \\
11 & 21.37 & 360, 255 & 449 & Quercetin & 232.00 \(\pm\) 0.18 & 974.960 \(\pm\) 0.28 *** \\
12 & 23.27 & 356, 256 & 303 & Kaempfer & 246.03 \(\pm\) 0.07 & 741.064 \(\pm\) 0.29 *** \\ \hline \hline \end{tabular}  
* The mean \(\pm\) SD (\(n=3\)) is provided in the descriptive statistics table. A two-way ANOVA was conducted to explore significant differences between fresh aronia and freeze-dried aronia by-product, followed by [PERSON]’s multiple comparisons test. In this analysis, the second column was compared to the first column. The following symbols indicate different levels of significance: *** for \(p<0.001\), B—by-product.  
\end{table} 
Table 3: _Cont._The aronia bar without powder has a very low amount of phenolic compounds (1115.61 \(\pm\) 0.91 \(\upmu\)g/g). Even more so, anthocyanins and flavonoids are not present.