## 3 Results and Discussion
### Thermogravimetric Analysis (TGA)  
The thermal degradation and weight loss with temperature change in order to understand thermal tolerance of films were determined using TGA [60]. TGA curves can demonstrate the thermal stability of a material and its fraction of volatile components by monitoring the change in weight [67]. The thermogravimetry (TG) curves are shown in Figure 3, and the thermal data of film weight loss in the four intervals are also summarized in Table 5. All the films incorporated with the nanoemulsion of TC showed the same thermal behavior, similar to the neat pectin film. The mass change occurred in three steps. The first Is the region between 20 and 180 \({}^{\circ}\)C, which corresponds to the water evaporation associated with the hydrophilic groups in the polymeric structure [57] and the volatile part of TC. The loss mass of pure pectin was 9.05%. However, the P/NE:1 film containing 5.00% of TC lost 12.50% of its mass in the first step. This is probably due to the vaporization of the volatile component of TC. The main degradation of pure pectin sample occurred at the temperature of 180 to 260 \({}^{\circ}\)C, which is associated with decarboxylation of carbon ring and degradation of the polymer backbone [59; 60]. There were no significant differences (\(p<0.05\)) in the mass loss  
Figure 3: TGA thermogram of the control (pure pectin) and film samples based on pectin incorporated with different concentrations of 5.00%, 3.33%, 2.50%, and 2.00% _trans_-cinnamaldehyde incorporated in pectin film named P/NE:1, P/NE:2, P/NE:3, P/NE:4. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **DSC** & \multicolumn{3}{c}{**ATG (\(\Delta\)m)**} & \multicolumn{1}{c}{**DTG**} \\ \hline
**Film Samples** & \(\mathbf{T_{g}}\)\({}^{\circ}\mathbf{C}\) & **20–180 \({}^{\circ}\mathbf{C}\)** & **180–260 \({}^{\circ}\mathbf{C}\)** & **260–600 \({}^{\circ}\mathbf{C}\)** & **20–600 \({}^{\circ}\mathbf{C}\)** &
\begin{tabular}{c} \(\mathbf{T_{max}}\)\({}^{\circ}\mathbf{C}\) \\ **Degradation** \\ \end{tabular} \\ \hline Pectin (control) & 152.94 & 9.05 \(\pm\) 0.39 \({}^{\mathrm{b}}\) & 41.63 \(\pm\) 1.23 \({}^{\mathrm{a}}\) & 19.67 \(\pm\) 1.06 \({}^{\mathrm{c}}\) & 70.36 \(\pm\) 0.22 \({}^{\mathrm{b}}\) & 234.83 \(\pm\) 0.28 \({}^{\mathrm{b}}\) \\ \hline P/NE:1 & 13.72 & 12.50 \(\pm\) 1.01 \({}^{\mathrm{a}}\) & 39.18 \(\pm\) 0.62 \({}^{\mathrm{a}}\) & 41.65\(\pm\) 2.73 \({}^{\mathrm{a}}\) & 92.33 \(\pm\) 1.10 \({}^{\mathrm{a}}\) & 239.16 \(\pm\) 0.76 \({}^{\mathrm{a}}\) \\ \hline P/NE:2 & 40.90 & 10.71 \(\pm\) 0.61 \({}^{\mathrm{ab}}\) & 39.25 \(\pm\) 0.95 \({}^{\mathrm{a}}\) & 40.99 \(\pm\) 4.17 \({}^{\mathrm{a}}\) & 91.95 \(\pm\) 2.31 \({}^{\mathrm{a}}\) & 239 \(\pm\) 1 \({}^{\mathrm{a}}\) \\ \hline P/NE:3 & 54 & 9.56 \(\pm\) 0.59 \({}^{\mathrm{b}}\) & 39.07 \(\pm\) 1.04 \({}^{\mathrm{a}}\) & 27.01 \(\pm\) 3.66 \({}^{\mathrm{b}}\) & 75.64 \(\pm\) 4.15 \({}^{\mathrm{b}}\) & 237 \(\pm\) 0.30 \({}^{\mathrm{ab}}\) \\ \hline P/NE:4 & 57 & 9.45 \(\pm\) 0.69 \({}^{\mathrm{b}}\) & 40.07 \(\pm\) 1.37 \({}^{\mathrm{a}}\) & 21.52 \(\pm\) 0.43 \({}^{\mathrm{bc}}\) & 71.14 \(\pm\) 0.24 \({}^{\mathrm{b}}\) & 236 \(\pm\) 0.43 \({}^{\mathrm{ab}}\) \\ \hline \hline \end{tabular}  
* The data are presented as the mean \(\pm\) one standard deviation (n = 3). Means that share identical letters show no significant differences (\(p<0.05\)).  
\end{table} 
Table 5: Thermal parameters of the films. of samples incorporated with TC and the pure pectin sample. The weight loss obtained ranged between 39.18 and 40.99% for samples ranging from pectin to P/NE:1. The last part of the weight loss occurred at the higher temperature, which is explained by the formation of partially destroyed solid char stacks with a polyaromatic structure [68]. The final weight loss of the film incorporated with TC is higher than pure pectin film, due to the exitance of an aromatic structure in the _trans_-cinnamaldehyde. The higher concentration of TC in pectin films resulted in higher weight loss at high temperatures.