# Characterization of Six Cold-Pressed Berry Seed Oils and Their Seed Meals
## 3 Results and Discussion
### Correlations between Parameters and Statistical Analysis  
When plotting different parameters against each other, it can be seen that an increase in the total polyphenols (TP) content causes the FRAP value to increase (see Figure 3). The latter was confirmed by an ANOVA analysis of all data using TP, total amount of mono-unsaturated fatty acids (MUFA), total amount of polyunsaturated fatty acids (PUFA), total amount of sterols, and total amount of tocopherols as factors. From Table 6, it can be seen that TP has a significant positive influence on FRAP. The latter is as expected since the antioxidant activity of edible oils has been ascribed to the presence of phenolic compounds [23].  
Figure 3: Total polyphenol content plotted against the FRAP value for all cold-pressed berry seed oil samples. Results are mean values of triplicates.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & & \multicolumn{3}{c}{**Tocophenols (mg/kg Oil)**} \\ \hline Plant Species & \(\alpha\) & \(\beta\) & \(\gamma\) & \(\delta\) \\ \hline Blackcurrant 1 & 239.6 & 35.2 & 14.0 & 239.7 \\ Blackcurrant 2 & 335.1 & 34.5 & 12.2 & 239.9 \\ \hline Raspberry 1 & 123.5 & 41.3 & 5.5 & 207.3 \\ Raspberry 2 & 133.7 & 32.0 & 7.3 & 210.9 \\ \hline Blackberry 1 & 57.1 & 22.6 & 6.5 & 555.2 \\ Blackberry 2 & 37.1 & 64.6 & 7.5 & 957.9 \\ \hline Blueberry 1 & \textless{}0.5 & 46.6 & \textless{}0.5 & 37.3 \\ Blueberry 2 & \textless{}0.5 & 57.4 & \textless{}0.5 & 36.1 \\ \hline Strawberry 1 & 55.0 & 57.5 & 4.9 & 87.8 \\ Strawberry 1 & 53.9 & 34.2 & 6.1 & 137.4 \\ \hline Sea Buckthorn 1 & 275.4 & 20.0 & 17.9 & 256.6 \\ Sea Buckthorn 2 & 393 & 3 & 15 & 306 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Tocopherol contents (mg/kg oil) in seed oils from different berry sources.  
When following the same approach for DPPH, it can be observed that the presence of tocopherols has a negative influence on the DPPH value (see Figure 4). The latter was once again confirmed by an ANOVA analysis using TP, PUFA, total amount of sterols, and total amount of tocopherols as factors (see Table 7). This result is unexpected since tocopherols are known for their radical scavenging activity [35], although recent publications also mention that tocopherols can also act as prooxidants [36].  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Source** & **Sum of Squares** & **df** & **Mean Square** & **F-Value** & _p-Value_ \\ \hline Model & 632,499 & 5 & 126,500 & 7.570 & 0.0143 \\ \hline TP & 189,778 & 1 & 189,778 & 11.356 & 0.0150 \\ \hline MUFA & 12,424 & 1 & 12,424 & 0.743 & 0.4217 \\ \hline PUFA & 13,664 & 1 & 13,664 & 0.818 & 0.4007 \\ \hline Sterols & 89 & 1 & 89 & 0.005 & 0.9443 \\ \hline Tocopherols & 192 & 1 & 192 & 0.011 & 0.9182 \\ \hline Residual & 100,269 & 6 & 16,712 & & \\ \hline Cor. total & 732,769 & 11 & & & \\ \hline \hline \end{tabular}
\end{table}
Table 6: ANOVA table for FRAP value (_p_-value < 0.05 indicates that a term is significant).  
Figure 4: Total tocopherol content plotted against the DPPH value for all cold-pressed berry seed oil samples. Results are mean values of triplicates.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Source** & **Sum of Squares** & **df** & **Mean Square** & **F-Value** & _p-Value_ \\ \hline Model & 4787 & 4 & 1197 & 5.865 & 0.0215 \\ \hline TP & 668 & 1 & 668 & 3.275 & 0.1133 \\ \hline PUFA & 342 & 1 & 342 & 1.674 & 0.2368 \\ \hline Sterols & 251 & 1 & 251 & 1.228 & 0.3044 \\ \hline Tocopherols & 1349 & 1 & 1349 & 6.610 & 0.0370 \\ \hline Residual & 1428 & 7 & 204 & & \\ \hline Cor. total & 6215 & 11 & & & \\ \hline \hline \end{tabular}
\end{table}
Table 7: ANOVA table for DPPH value (_p_-value < 0.05 indicates that a term is significant).