# The Study of Thermal Properties of Blackberry, Chokeberry and Raspberry Seeds and Oils
## 3 Results and Discussion
### Study of Seeds
#### 3.1.4 TG/DTG of Seeds  
The results of the TG analysis are TG curves with calculated and graphically presented first derivatives, which refers to a mass loss of sample as a consequence of thermal decomposition, presented in Figure 2. The pyrolysis behaviors of all the studied seeds were similar. Considering milled seeds tested under a nitrogen atmosphere, small mass losses of up to 3% occurred first, at temperature ranges of 50-140 \({}^{\circ}\)C; these were a consequence of water and volatile compounds' evaporation from samples. The next two incidents of mass losses at temperatures of 120-230 \({}^{\circ}\)C were connected to carbohydrates degradation. The largest decomposition of samples (49% for blackberry seeds, 44% for raspberry seeds, and 30% for chokeberry seeds) occurred at temperatures of 300-500 \({}^{\circ}\)C and were due to the further pyrolysis of organic compounds: carbohydrates and also fat. As it comes to whole seeds tested under a nitrogen atmosphere, the mass losses resulting from thermal decomposition occurred in a different range of variability for temperatures. The first degradation, due to water and volatile compounds evaporation, was present up to a temperature of around 160 \({}^{\circ}\)C. Second mass losses at around 160-300 \({}^{\circ}\)C were combined with carbohydrates pyrolysis. The two largest mass losses at temperatures of 300-375 \({}^{\circ}\)C and 375-550 \({}^{\circ}\)C were due to fat and further organic compounds degradation. [PERSON] et al. obtained comparable courses of thermogravimetric curves for cherry seeds; the weight losses were observed at a temperature range of 200-500 \({}^{\circ}\)C, although the highest mass losses were registered at temperatures characteristic of saccharides decomposition [33]. In the TG study conducted under a nitrogen atmosphere, 27-36% of the mass of the sample remained undegraded in the range of temperatures from the following study. The remaining part was ash, containing thermostable inorganic compounds. The TG analysis under an oxygen atmosphere resulted in curves with three to four weight losses for milled seeds. Chokeberry and blackberry seeds were decomposed in four main steps; chokeberry seeds--with first two losses of about 3% at 50-125 \({}^{\circ}\)C and 12% at 125-240 \({}^{\circ}\)C and two following almost equal losses of 42% at 240-370 \({}^{\circ}\)C and at 370-515 \({}^{\circ}\)C of 41% weight; blackberry seeds--with a loss of over 7% at 50-190 \({}^{\circ}\)C, 8% at 190-240 \({}^{\circ}\)C, and the next two similar as in the samples of blackberry seeds: 44% at 240-370 \({}^{\circ}\)C and 36% at 370-515 \({}^{\circ}\)C. In the case of the raspberry seeds TG curve, three weight losses were registered, around 14% of the mass was lost at 50-220 \({}^{\circ}\)C, 48% at 20-380 \({}^{\circ}\)C, and 35% at 380-500 \({}^{\circ}\)C. The first events occurring at lower temperatures of up to 125 \({}^{\circ}\)C for chokeberry and 190 \({}^{\circ}\)C for blackberry seeds are a result of moisture and volatile compounds evaporation from the sample. Following events of decomposition at temperatures that range up to 515 \({}^{\circ}\)C are connected to organic compounds degradation, i.e., saccharides and lipids. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Source of Seeds** & \(\rm T_{g}\) **Onset (\({}^{\circ}\)C)** & \(\rm T_{g}\) **Midpoint (\({}^{\circ}\)C)** & \(\rm T_{g}\) **Endpoint (\({}^{\circ}\)C)** \\ \hline Blackberry & 73.66 \(\pm\) 1.46 & 74.09 \(\pm\) 1.23 & 74.11 \(\pm\) 1.41 \\ Chokeberry & 55.14 \(\pm\) 0.89 & 55.27 \(\pm\) 0.78 & 55.40 \(\pm\) 1.08 \\ Raspberry & 28.26 \(\pm\) 0.17 & 29.31 \(\pm\) 0.11 & 30.36 \(\pm\) 0.15 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Experimental glass transition temperatures of studied berries seeds. seeds.