# The Study of Thermal Properties of Blackberry, Chokeberry and Raspberry Seeds and Oils
## 3 Results and Discussion
### Study of Oil Obtained from Seeds
#### 3.2.2 Gas Chromatography (GC) of Extracted Oils  
The results of the gas chromatography study are chromatograms; the blackberry seed oil chromatogram is presented as an example in Figure 3. The fatty acids profile of extracted berries seed oils is presented in Table 3. Based on the obtained results, it can be seen that the studied oils are rich in unsaturated fatty acids, especially polyunsaturated fatty acids. In raspberry seed oil, unsaturated fatty acids percentage is the highest from studied oils and values at a level of over 94%. In all of the extracted fats, the main group of unsaturated fatty acids are polyunsaturated fatty acids. The percentage of monounsaturated fatty acids ranges from 11.95 \(\pm\) 0.00% to 18.21 \(\pm\) 0.06% for raspberry seed oil and chokeberry seed oil, respectively. For the extracted oils, the most abundant fatty acid was linoleic acid (C 18.2) with values of 62.53 \(\pm\) 0.06%, 67.62 \(\pm\) 0.04%, and 51.44 \(\pm\) 0.04% for blackberry, chokeberry, and raspberry seeds oils, respectively. The second most frequent fatty acid considering blackberry and raspberry seed oils was \(\alpha\)-linoleic acid, with percentages ranging from 16.19 \(\pm\) 0.01% for blackberry seed oil and 30.56 \(\pm\) 0.04% for raspberry seed oil, in the case of chokeberry seed oil, oleic acid ranged from 17.48 \(\pm\) 0.04%.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Fatty Acid** & **Blackberry Seed Oil** & **Chokeberry Seed Oil** & **Raspberry Seed Oil** \\ \hline C 16:0 & 4.52 \(\pm\) 0.19 & 5.44 \(\pm\) 0.02 & 2.92 \(\pm\) 0.03 \\ C 16:1 & 0.13 \(\pm\) 0.01 & 0.15 \(\pm\) 0.01 & 0.08 \(\pm\) 0.01 \\ C 18.0 & 2.87 \(\pm\) 0.03 & 1.39 \(\pm\) 0.07 & 1.45 \(\pm\) 0.  
The obtained results are consistent with previous findings. [PERSON] et al. [34] studied the fatty acid composition of blackberry and raspberry seed oils extracted in the Soxhlet apparatus. Blackberry oil consisted of 83.78%, 8.40%, and 6.49% of PUFA, MUFA, and SFA, respectively. In raspberry oil, PUFA accounted for 81.05%, MUFA 12.81%, and SFA 4.13%. In both oils, linoleic acid is the most abundant fatty acid. In another study, the blackberry and raspberry seed oil proportions of fatty acid groups were: 74.94%, 17.87%, and 7.13% in blackberry oil and 82.52%, 13.21%, and 4.23% in raspberry oil for PUFA, MUFA and SFA, respectively [36]. Chokeberry seed oil extracted using chloroform and methanol as solvents consisted of 73.58% of PUFA, 16.91% of MUFA, and 9.51% of SFA, with a linoleic acid occurring as a dominant [37]. The specific fatty acid composition affects oil properties. High values of PUFA may result in a decreased oxidative stability of the plant oils [38]. However, oils rich in PUFA show high nutritional value as they are recommended by FAO/WHO as an SFA replacement in diet [39]. Considering novel nutritional indices of fat, PUFA/SFA ratios of berry seed oils, ranging 9.13, 9.20, and 15.55 for blackberry, chokeberry, and raspberry oils, respectively, are values adequate enough to classify berry seed oils as nutritionally valuable [40].