## 2 Results and Discussion  
### Determination of Total Polyphenols, Flavonoids, and Phenolic Acids in Chocolates  
Cocoa beans, and consequently also chocolate, are rich sources of antioxidant compounds, mainly catechins or flavan-3-ols, anthocyanins, and proanthocyanidins [22]. The primary catechin is (-)-epicatechin and according to [PERSON] et al. [23] its contents in cacao beans and powder were 4.61 and 3.81 mg/g, respectively, while total polyphenols were 34-60 and 20-62 mg/g (respectively). The anthocyanin fraction consists mainly of cyanidin-3-\(\alpha\)-\(\iota\)-arabinoside and cyanidin-3-\(\beta\)-\(\iota\)-galactosidase, while procyanidins are mostly flavan-3,4-diols [22]. The profile of the polyphenic compounds of the cocoa beans will, thus, also influence the antioxidant value of the chocolate obtained therefrom. Total content of polyphenols, flavonoids, and phenolic acids in the studied samples was determined. The results of total polyphenols were calculated and expressed as gallic acid equivalents, total flavonoid content as quercetin equivalents, and total phenolic acids content as caffe acid equivalents, as shown in Table 1.  
The highest polyphenol content was found in blend chocolate with 90% cocoa solids. On the other hand, the lowest polyphenol content was found in blend chocolate with 100% cocoa solids. The differences between single-origin chocolates in the content of total polyphenols were not significantly important. However, the differences between blend chocolates may be explained by geographical and vegetal factors as the nature of soil, cultivation and fermentation conditions, climate, and cultivar [24]. Because polyphenols are stored in the non-fat cocoa solids, chocolates with a higher cocoa content are considered to be better sources of these compounds, which have a higher antioxidant capacity [25]. Although our results are in accordance with previously reported data [26], they cannot be directly compared due to differences in the solvent used and presentation of the results. A strong positive correlation (R\({}^{2}\) = 0.9) was found between the total content of polyphenols and flavonoids, as well as phenolic acids. The total content of flavonoids was high in samples of blend chocolates with 80 and 90% of cocoa solids and in samples of single-origin cocoa chocolate. The lowest content of total flavonoids was found in the blend chocolate with 100% cocoa solids. The content of total phenolic acids correlated with the content of flavonoids (R\({}^{2}\) = 0.9), as well as the highest and the lowest content of phenolic acids. To this date, it is not entirely clear why phenolic acids usually contribute significantly to the phenolic profile of studied samples, especially chocolates [27]. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Sample** & **TPC [g/kg]** & **TFC [g/kg]** & **TPAC [g/kg]** \\ \hline blend80 & \(14.12\pm 0.62\)\({}^{\text{b}}\) & \(0.31\pm 0.08\)\({}^{\text{a}}\) & \(13.06\pm 0.27\)\({}^{\text{b}}\) \\ blend90 & \(23.58\pm 1.38\)\({}^{\text{a}}\) & \(0.44\pm 0.02\)\({}^{\text{a}}\) & \(16.64\pm 0.01\)\({}^{\text{a}}\) \\ blend100 & \(4.83\pm 0.04\)\({}^{\text{c}}\) & \(0.19\pm 0.15\)\({}^{\text{b}}\) & \(8.46\pm 0.01\)\({}^{\text{d}}\) \\ Origin Madagascar & \(21.76\pm 0.44\)\({}^{\text{a}}\) & \(0.31\pm 0.04\)\({}^{\text{a}}\) & \(13.48\pm 0.28\)\({}^{\text{b}}\) \\ Origin Vietnam & \(21.00\pm 0.84\)\({}^{\text{a}}\) & \(0.27\pm 0.00\)\({}^{\text{a}}\) & \(13.84\pm 0.08\)\({}^{\text{b}}\) \\ Origin Honduras & \(18.78\pm 1.11\)\({}^{\text{a,b}}\) & \(0.37\pm 0.02\)\({}^{\text{a}}\) & \(12.39\pm 0.31\)\({}^{\text{c}}\) \\ \hline \hline \end{tabular} Values represent mean \(\pm\) standard deviation (\(n\) = 3). Values followed by the same letter in superscript within the same column were not significantly different (\(p<0.05\)), according to [PERSON]’s test. TPC—total phenolic content expressed as gallic acid equivalent, TFC—total flavonoid content expressed as quercetin equivalent, TPAC—total phenolic acids’ content expressed as caffe acid equivalent.  
\end{table}