## 3 Results and Discussions
### Volatile Compounds of Raw and Roasted Flaxseed  
The purpose of the analysis was to compare the volatile compounds profile of both raw and roasted flaxseed, to explain, based on the identified volatile compounds, consumers' acceptability of roasted seeds. As a result, a total number of 18 aroma compounds were identified by using ITEX/GS-MS and are presented in Table 3 group in six classes of compounds: alcohols, aldehydes, ketones, terpen, and terpenoids, acids and others. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameters** & **Wheat Flour Type 000 (WF) \({}^{*}\)** & **Roasted Flaxseed Flour (RFSF) \({}^{*}\)** \\ \hline Moisture (\%, fw) & 14.55 \(\pm\) 1.20 \({}^{\text{b}}\) & 1.64 \(\pm\) 0.04 \({}^{\text{a}}\) \\ Protein (\%, fw) & 9.12 \(\pm\) 1.03 \({}^{\text{a}}\) & 21.40 \(\pm\) 1.50 \({}^{\text{b}}\) \\ Ash (\%, fw) & 0.48 \(\pm\) 0.01 \({}^{\text{a}}\) & 3.95 \(\pm\) 0.04 \({}^{\text{b}}\) \\ Fat (\%, fw) & 1.03 \(\pm\) 0.20 \({}^{\text{a}}\) & 42.50 \(\pm\) 1.50 \({}^{\text{b}}\) \\ Crude fiber (\%, fw) & 0.37 \(\pm\) 0.23 \({}^{\text{a}}\) & 8.75 \(\pm\) 1.45 \({}^{\text{b}}\) \\ Total carbohydrate (\%, fw) & 74.45 \(\pm\) 0.9 \({}^{\text{b}}\) & 21.76 \(\pm\) 0.76 \({}^{\text{a}}\) \\ \hline \hline \end{tabular} \({}^{*}\) Values represent mean of three independent determinations \(\pm\) SD; Mean values followed by the same superscript alphabet in the row are not significantly different at \(p<0.05\) according to Duncan comparison test; fw-fresh weight.  
\end{table} 
Table 2: Proximate composition of raw materials. It was found that the main volatile compounds of raw flaxseed were hexan-1-ol (23.06%), acetophenone (13.22%), \(\alpha\)-pinene (12.70%), D-limonene (10.72%) and on the other hand, the major volatile compounds in the roasted flaxseed were hexanl (24.24%), acetophenone (17.28%), benzahdehyde (10.42%), D-limonene (9.85%), \(\alpha\)-pinene (6.81%), 3-methylbutan-1-ol (4.48%) and hexan-1-ol (3.74%), respectively (Table 3). Compounds with fresh and baslamic aroma characteristics, for example hexan-1-ol, benzophenone, \(\beta\)-pinene, D-limonene, camphene and benzoic acid, were present in significantly higher (\(p<0.05\)) amounts in raw flaxseed compared to roasted flasseed. With respect to hexan-1-ol, a lipid oxidation volatile compound with a significant value in raw flaxseed, its amount could be justified by the activity of dehydrogenase enzyme during storage [53]. In the roasted flaxseed compounds with aromas like malt, burned sugar and almond were found in significantly higher amounts (\(p<0.05\)) than in raw flaxseed. Hexanal is the primary oxidation product of linoleic acid [52]. The increase of hexanal in roasted flaxseed reaching a final value of 24.24% may be due to lipid oxidation during thermal treatment [54]. Roasted flaxseeds are a rich source of lipids and in the present study, a total amount of 42.50% total fat was previously mentioned. Furthermore, [PERSON] et al. [53] reported a higher content of \(\alpha\)-linolenic acid, the precursor of docosahexaenoicenoic and eicosapentaenoic acids, in flaxseeds, thus explaining the formation of hexanal during the roasting process. Furthermore, acetophenone (17.28%) was the major volatile compound from the ketone group, while the main alcohol identified was 3-methylbutan-1-ol (4.48%). The presence of aldehydes, ketones and alcohols in the roasted flaxseeds could be justified by thermal reactions during roasting such as non-enzymatic Maillard reactions and sugar caramelization. Likewise, the aforementioned compounds could also be formed as a result of lipid oxidation [54].