# Use of Bilberry and Blackcurrant Pomace Powders as Functional Ingredients in Cookies
## 3 Results and Discussion  
### Characterization of Wild Bilberry and Blackcurrant Pomace Powders  
The results concerning the proximate composition, titratable acidity, total phenolic content, and DPPH radical scavenging activity of BIPP and BCPP are given in Table 1.  
Both powders showed low water content (bellow 10%), which suggests the physical and microbiological stability of these ingredients. BIPP showed significantly (\(p<0.05\) \begin{table}
\begin{tabular}{l c c} \hline  & **BIPP** & **BCPP** \\ \hline Dry matter (g/100 g) & 88.97 \(\pm\) 0.66 \({}^{\text{a}}\) & 89.41 \(\pm\) 0.57 \({}^{\text{a}}\) \\ \hline Protein (g/100 g) & 8.25 \(\pm\) 0.29 \({}^{\text{a}}\) & 6.78 \(\pm\) 0.26 \({}^{\text{b}}\) \\ \hline Fat (g/100 g) & 8.27 \(\pm\) 0.26 \({}^{\text{b}}\) & 9.32 \(\pm\) 0.28 \({}^{\text{a}}\) \\ \hline Fiber (g/100 g) & 12.14 \(\pm\) 0.43 \({}^{\text{a}}\) & 10.64 \(\pm\) 0.58 \({}^{\text{b}}\) \\ \hline Ash (g/100 g) & 1.03 \(\pm\) 0.15 \({}^{\text{a}}\) & 1.07 \(\pm\) 0.12 \({}^{\text{a}}\) \\ \hline Titratable acidity (g citric acid/100 g) & 4.63 \(\pm\) 0.19 \({}^{\text{b}}\) & 5.82 \(\pm\) 0.16 \({}^{\text{a}}\) \\ \hline Water solubility index (WSI, \%) & 19.32 \(\pm\) 0.57 \({}^{\text{a}}\) & 14.05 \(\pm\) 0.82 \({}^{\text{b}}\) \\ \hline Water absorption capacity (WAC, \%) & 378.31 \(\pm\) 2.17 \({}^{\text{a}}\) & 312.38 \(\pm\) 2.72 \({}^{\text{b}}\) \\ \hline Total phenolic content (mg GAE/100 g) & 3595.11 \(\pm\) 0.65 \({}^{\text{a}}\) & 953.45 \(\pm\) 0.37 \({}^{\text{b}}\) \\ \hline DPPH radical scavenging activity (mmol Trolox/100 g) & 11.78 \(\pm\) 0.17 \({}^{\text{a}}\) & 2.35 \(\pm\) 0.12 \({}^{\text{b}}\) \\ \hline \end{tabular}
\begin{tabular}{l c} Different lowercase letters indicate significant differences between pomace powders (\(p<0.05\)); BIPP—bilberry pomace powder; BCPP—blackcurrant pomace powder. \\ \end{tabular}
\end{table} 
Table 1: Proximate composition, physiochemical, and functional properties of bilberry and blackcurrant pomace powders. higher protein and fiber but lower fat content as compared with BCPP, while no significant differences were found concerning the dry matter and ash content. A protein content of 6.78% was found in blackcurrant pomace powder, compared to 8.25% in bilberry pomace powder. [PERSON] et al. (2014) also found 6.9% protein contents in blackcurrant pomace flour, while [PERSON] et al. (2017) reported a protein content of 6.85% in red currant pomace powder. [PERSON] et al. (2016) demonstrated that bilberry and blackcurrant pomace powders are a source of oils rich in mono- and polyunsaturated fatty acids, with BIPP being richer in n-3 PUFA (n-6/n-3 = 0.90) than BCPP (n-6/n-3 = 1.28). Extremely high values of the total phenolic content were found both in BIPP and BCPP, suggesting that the press cake left after bilberry and blackcurrant juice extraction holds a large fraction of the fruit's phenolic compounds. Similar values for the total phenolic content have been confirmed in previous studies ([PERSON] et al., 2016; Bileparries and blackcurrants display high antioxidant activity due to their richness in phenolic compounds, especially anthocyanins ([PERSON] et al., 2016). Significantly higher (\(p\) < 0.05) values of total phenolic content and DPPH radical scavenging activity were found in BIPP as compared with BCPP. The tittatable acidity found in BCPP (5.82 g citric acid/100 g) was significantly higher than in BIPP (4.63 g citric acid/100 g), which will impact the taste and flavor of the supplemented cookies. Similar values of tittatable acidity have been reported previously in blackcurrant pomace powders ([PERSON] et al., 2016). Table 1 also presents the results concerning the water solubility index (WSI) and water absorption capacity (WAC) of BIPP and BCPP. WAC is defined as the ability of the powdery product to hold or retain water against gravity, comprising bound, hydrodynamic, capillary, and physically entrapped water ([PERSON] et al., 2016), being a major functional property in food applications.