## 3 Results and Discussion
#### 3.2.2 Mechanical Properties  
Mechanical properties, including elongation at break (EAB) and tensile strength (TS) of the films, were measured and the results are showed in Table 3. GLG and GMC films showed no significant difference in EAB compared to the control film. However, all other tested additives produced an increase to EAB, with gac oil producing the largest increase (21.99 \(\pm\) 0.49 mm). The results indicated that incorporation of essential oils and plant extracts tend to increase the EAB of the films. The results are supported by previous studies ([PERSON] et al., 2016; [PERSON] et al., 2017; [PERSON] et al., 2018; [PERSON] et al., 2019; [PERSON] et al., 2019), and can be explained by the formation of cross-links that contribute to better cohesive and flexible structure of the composite films when adding essential oils.  
The results also revealed that addition of lemon myrtle oil and extract significantly reduced the tensile strength of gac pulp-based edible films (\(p\) < 0.05). There was no significant difference in tensile strength caused by the inclusion of any other tested ad  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Samples** & **L** & **a** & **b** & **\(\Delta\)E** & **Chroma** & **Hue Angle** \\ \hline GP & 95.55 \(\pm\) 0.33 a  & \(-\)0.33 \(\pm\) 0.03 d  & 4.63 \(\pm\) 0.09 f  & 2.2 \(\pm\) 0.90 f  & 4.95 \(\pm\) 0.99 f  & 94.05 \(\pm\) 0.3 e  \\ GPP & 95.55 \(\pm\) 0.44 a  & \(-\)0.34 \(\pm\) 0.05 d  & 4.21 \(\pm\) 0.32 f  & 1.87 \(\pm\) 0.39 g  & 4.22 \(\pm\) 0.32 f  & 94.55 \(\pm\) 0.38 deg  \\ GGG & 95.82 \(\pm\) 0.06 a  & \(-\)0.41 \(\pm\) 0.02 de  & 4.61 \(\pm\) 0.13 f  & 2.09 \(\pm\) 0.14 f  & 4.63 \(\pm\) 0.13 f  & 95.13 \(\pm\) 0.17 c  \\ GLG & 95.86 \(\pm\) 0.08 a  & \(-\)0.55 \(\pm\) 0.03 e  & 5.34 \(\pm\) 0.13 d  & 2.78 \(\pm\) 0.15 de  & 5.36 \(\pm\) 0.13 d  & 95.88 \(\pm\) 0.2 b  \\ GPM & 95.77 \(\pm\) 0.05 a  & \(-\)0.42 \(\pm\) 0.01 d  & 4.57 \(\pm\) 0.16 f  & 2.07 \(\pm\) 0.15 f  & 4.59 \(\pm\) 0.16 f  & 95.2 \(\pm\) 0.15 d  \\ GLO & 95.7 \(\pm\) 0.06 a  & \(-\)0.56 \(\pm\) 0.01 e  & 5.19 \(\pm\) 0.08 deg  & 2.69 \(\pm\) 0.09 d  & 5.22 \(\pm\) 0.08 deg  & 96.21 \(\pm\) 0.1 b  \\ GGO & 95.8 \(\pm\) 0.16 a  & -0.76 \(\pm\) 0.03 f  & 5.78 \(\pm\) 5.24 d  & 3.26 \(\pm\) 0.27 d  & 5.83 \(\pm\) 0.24 d  & 97.54 \(\pm\) 0.2 a  \\ GLE & 79.87 \(\pm\) 0.24 d  & 2.27 \(\pm\) 0.18 a  & 23.95 \(\pm\) 0.86 a  & 27.11 \(\pm\) 0.63 a  & 24.06 \(\pm\) 0.87 a  & 84.6 \(\pm\) 0.25 f [FONOTE:f]Footnote f: footnotemark: [ENDFOOTNOTE] \\ GBA & 86.55 \(\pm\) 0.31 b  & 1.27 \(\pm\) 0.04 c  & 11.83 \(\pm\) 0.31 c  & 13.6 \(\pm\) 0.29 c  & 11.9 \(\pm\) 0.3 c  & 83.87 \(\pm\) 0.53 g  \\ \hline \end{tabular} Data are means \(\pm\) standard deviations. Data in the same column not sharing similar letters are significantly different at \(p\) < 0.05.  
\end{table}
Table 2: Effects of essential oils and plant extracts on colour of the seaweed hydrocolloid and gac pulp edible films.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Samples** & **WVP (\(\times\)10\({}^{-10}\) g Pa\({}^{-1}\) s\({}^{-1}\) m\({}^{-1}\))** & **EAB (mm)** & **TS (N/m)** \\ \hline GP & 1.76 \(\pm\) 0.08 ab  & 15.76 \(\pm\) 0.26 c  & 1364.78 \(\pm\) 92.10 ab  \\ GPP & 1.25 \(\pm\) 0.011 d  & 19.76 \(\pm\) 1.67 abditives. This is in agreement with previous studies [42; 57; 59; 60]. The decrease in TS can be explained by the weak bonds between lemon myrtle oil and extract with film-forming polymers [17; 59]. Thus, the current findings revealed that incorporation of plant oils and extracts can significantly increase EAB, but may also reduce the TS of the films.  
Impact of Essential Oils and Plant Extracts on Structure of the Seaweed Hydrocolloid and Gac Pulp Edible Films